EVOLUTION & GENETIC NEWS, Gaia Church

EVOLUTION
& GENETIC
NEWS '06
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EVOLUTION NEWS, 2006

. Dec 27, 06: Kenneth Catania, a biologist at Vanderbilt University, U.S., discovered that moles and shrews can smell underwater, which was considered impossible by scientists for a long time.
. . Catania's first clues came in the 1980s, when he was a graduate student studying star-nosed moles, which hunt for prey underground and underwater. Catania noticed that when they were underwater, they sometimes released a stream of bubbles, at about two bubbles a second. If the moles were holding their breath, it did not make much sense for them to be leaking.
. . He noticed that the star-nosed moles were actually producing up to a dozen bubbles each second, but most of the bubbles never detached from their noses. Instead, the animals sucked the bubbles back in. The bubbles resembled the puffs of air the moles used to smell objects out of water, Catania noticed. To test that idea, he ran an experiment. He laid down an underwater scent trail leading to little bits of food. The moles could follow the trails with great accuracy which led him to believe that they were using the air bubbles to smell.
. . Catania wondered if any other mammals could sniff underwater. He tested water shrews, which are known to swim for their prey. In the scent trail test, he found, the water shrews did as well as the star-nosed moles.
. . Bubble-sniffing is a striking example of how evolution tinkers with bodies, rather than rebuilding them from scratch, he suggested.

Dec 22, 06: Wah, wow, hoo! Turns out humans aren't the only primates using songs to warn of life's dangers and travails. White-handed gibbons in Thailand's forests have been found to communicate threats from predators by singing -—the first time the behavior has been discovered among non-human primates, researchers said.
. . While other animals have been shown to use song to attract mates or signal danger, researchers writing in this month's science journal PLoS One said their study was the first to show gibbons issuing song-like warnings to each other. The sounds made when encountering a predator were more chaotic and louder than those used to win over a mate, Clarke said. "Gibbons can rearrange their songs to denote different circumstances, much like we do with words", she said.

Dec 24, 06: it has been stated by many authors that when we make contact with alien beings, they may be the robotic progeny of beings similar to ourselves. Perhaps probes have been sent here with enough intelligence to carry on an engaging conversation. Is it possible they are waiting for us to be smart enough to construct a robot that can talk to them? ~Adrian Brown, SETI Institute.

Dec 21, 06: The discovery of fossilized remains of a mouse-like animal that lived at least 16 million years ago is the first hard evidence that New Zealand had its own indigenous land mammals. Until now, the only fossils discovered in New Zealand were those of flying mammals like bats as well as birds and marine mammals.
. . NZ paleontologist Trevor Worthy and his team say they discovered two parts of a jaw and a femur (thighbone) —-about the size of a fingernail. The creature probably looked like a "little rat", weighing around 3.5 ounces and measuring about 4 inches with a pointy snout.
. . New Zealand is believed to have split from Gondwana about 82 million years ago and other continents soon followed.
. . The discovery cast doubt on theories that New Zealand was submerged from 25 million to 30 million years ago and later re-colonized by plant and animal species from nearby land masses like Australia.
. . "The mouse-like animal was living in NZ about 16 million to 19 million years ago", he said. "The inference you can then make is that animal has a history where its ancestors lived on New Zealand from the time New Zealand split from Gondwana." Worthy said its ancestors could have lived up to 82 million years ago.
. . But other paleontologists said there is not enough evidence to support Worthy's hypotheses, noting fossil fragments found so far are more like tantalizing clues than solid proof that this was a land-roaming mammal rather than a bat. "I think it's interesting but I think they need to find better stuff", said Tom Rich, the curator of vertebrae paleontology at the Museum Victoria in Melbourne. "What they have now is tantalizing but ... it is not definitive. If they had one tooth in that jaw, that would make a lot of difference. A tooth, in particular molar, would be decisive in determining whether you have a terrestrial mammal or a bat."

Dec 21, 06: The fossil bones of what may have been Europe's largest animal ever, a new type of dinosaur, have been discovered in Spain. The sauropod is estimated to have weighed between 40 and 48 tons in the late Jurassic period, about 150 million years ago.

Dec 20, 06: The sensitivity of the human sense of smell has been significantly underestimated, a study suggests. US research had confounded the established belief that people have a poorer sense of smell than other animals.
. . The work asked people to follow scents on the ground, as a dog would do, and found they were as good. A UK expert said the findings were "intriguing" and would aid better understanding of the sense. It is not the second class system that has been the traditional assumption.
. . The researchers from University of California Berkley laid scent trails, including one of chocolate essential oil, in a grassy field, and asked 32 people to find the 10 meter trail and track it to the end. Those who took part were blindfolded and wore thick gloves and earplugs to force them to rely exclusively on smell. Two thirds were able to follow the scent. And while they remained slower than the other animals at tracking scents, their performance improved over time.

Dec 20, 06: Flora, a pregnant Komodo dragon living in a British zoo, is expecting eight babies in what scientists said could be a virgin birth.
. . Flora has never mated, or even mixed, with a male dragon, and fertilized all the eggs herself, a process culminating in parthenogenesis, or virgin birth. Other lizards do this, but scientists only recently found that Komodo dragons do too. Parthenogenesis) has never been seen in such a large species.
. . It could help them understand how reptiles colonize new areas. A female dragon could, for instance, swim to another island and establish a new colony on her own. "The genetics of self-fertilization in lizards means that all her hatchlings would have to be male. These would grow up to mate with their own mother and therefore, within one generation, there would potentially be a population able to reproduce normally on the new island", Buley added.

Dec 14, 06: During the age of dinosaurs, tiny squirrel-like creatures climbed trees and jumped. Then they spread their limbs and glided away —-the first known mammals to take to the air, a new report says.
. . The species is revealed by a fossil find in northeastern China, which pushes the known history of mammalian gliding or flying back by more than 75 million years. The creature may have even beaten birds into the air.
. . Like today's flying squirrels, it stretched a furry membrane between its limbs to provide an airfoil for gliding after it jumped from a tree. But it's not related to anything living today. Scientists don't know exactly when the animal lived. Its remains could be anywhere from 130 million to 164 million years old. So it's clearly older than the 51 million-year-old bat that used to be the oldest evidence of flying or gliding in a mammal. And it has a chance of preceding the earliest known bird, Archaeopteryx, which flew about 150 million years ago. It is much younger than flying reptiles called pterosaurs, which are dated from 230 million years ago.
. . They believe it was nocturnal, like other mammals of the time were thought to be, and like gliding mammals are today. It was the size of a flying squirrel or a bat —-less than three ounces. Its stiff tail might have been longer than the trunk of its body.
. . The find includes not only bones, but also impressions left in rock that reveal the furry membrane the creature used for gliding. Its teeth show it ate mostly insects, researchers said. But it probably couldn't hunt insects while gliding because it was too clumsy a flier and couldn't stay airborne long enough.

Dec 7, 06: Birds living in cities are performing a type of "avian rap" while their rural counterparts are sticking to more traditional sounds, a study shows.
. . Dutch researchers found that urban species of birds sing short, fast songs rather than the slower melodies of countryside birds. City birds also sing at a higher pitch and will try out different song types. Experts said city birds have adapted to counter background noise and increase their chances of finding a mate.

Dec 6, 06: Bats use the earth's magnetic field to navigate and one species has a huge tongue that is longer than its entire body, researchers said. In two separate studies, scientists in the US have revealed unusual characteristics of the winged mammal.
. . Richard Holland of Princeton U showed the homing devices of big brown bats can be altered by artificially shifting the Earth's magnetic field, indicating the animals depend on a magnetic compass to travel.
. . In another study, Nathan Muchhala, of the U of Miami, Coral Gables, taught the nectar bat Anoura fistulata to drink from a modified straw to measure its 85 mm tongue, which is 1.5 times longer than its body. The bat, which stows its lengthy tongue in its rib cage, pollinates a plant with tubes of the same length. Muchhala suggests the extreme length of the bat's tongue co-evolved with the long flowers of the plant.

Dec 5, 06: Starvation and cannibalism were part of everyday life for a population of Neandertals living in northern Spain 43,000 years ago, a study suggests. Bones and teeth from the underground cave system of El Sidron in Asturias bear the hallmarks of a tough struggle for survival, researchers say.
. . Analysis of teeth showed signs of starvation or malnutrition in childhood and human bones have cut marks on them. Some bones appeared to have been dismembered and broken open, possibly to allow access to marrow and brains. "Given the high level of developmental stress in the sample, some level of survival cannibalism would be reasonable", the scientists wrote.
. . Dr Rosas and colleagues found a north-south variation in Neandertal jaw bones, suggesting that populations from southern parts of Europe had wider, flatter faces.

Dec 1, 06: Hollow spheres found in a primordial meteorite could yield clues to the origin of life on Earth. Scientists say that "bubbles" like those in the Tagish Lake meteorite may have helped along chemical processes important for the emergence of life.
. . The globules could also be older than the Solar System; their chemistry suggests they formed at temperatures of about -260C, near "absolute zero". Analysis of the bubbles shows they arrived on Earth in the meteorite and are not terrestrial contaminants. These hollow spheres could have provided a protective envelope for the raw organic molecules needed for life. The hollow spheres seem to be empty, but they do have organic molecules on their surfaces.
. . Mike Zolensky, a Nasa mineralogist, commented: "If, as we suspect, this type of meteorite has been falling on to Earth throughout its entire history, then the Earth was seeded with these organic globules at the same time life was first forming here. We can estimate that there are billions of them in this meteorite."
. . The ratios of different forms, or isotopes, of the elements hydrogen and nitrogen in the meteorite are very unusual, which suggests the structures did not come from Earth, say the scientists. "The isotopic ratios in these globules show that they formed at temperatures of about -260C, near absolute zero."

Nov 30, 06: A single, gigantic asteroid slammed into Earth 65 million years ago, dooming the dinosaurs and many other species, scientists said today, in a new study rebutting theories that multiple impacts did the deed.
. . An examination of rock sediments drilled from five sites at the bottom of the Atlantic Ocean strongly supports the notion that one massive hunk of space rock caused the mass extinction, a research team led by University of Missouri-Columbia geology professor Ken MacLeod found.
. . A group of researchers led by Princeton University's Gerta Keller has advanced a competing theory that the impact that created the Chicxulub crater actually predated the end of the dinosaurs by 300,000 years and did not cause the mass extinction. They propose that one or more additional big hunks of space rock later hit the Earth and finished the job, but the impact craters they would have left behind have not yet been found.
. . MacLeod's team examined sediment drilled far below the sea surface about 2,800 miles from the Yucatan impact site, a location they believed to be ideal. Any rock samples taken too close to the crater may be altered by events that occurred immediately after the impact, like waves, earthquakes and landslides. Samples taken too far away may contain too little debris evidence from the impact. The samples they examined boasted a telltale layer of impact-related material, but there was none on top or below --indicating, they argued, there were no other impacts.

Nov 30, 06: Giant kangaroos and wombats bigger than cars which once roamed Australia were killed by climate change and not human hunters, Australian scientists said. The report comes as the country struggles with what could be its worst drought in 1,000 years, affecting more than half its farmlands.
. . Known as megafauna, the huge animals were driven into extinction by a steady warming of Australia's climate, which in turn saw a once-lush outback region turn to red desert and grasslands.
. . Scientists have said that Australia must brace itself for long-term climate change and water shortages due to the accelerating pace of global warming.

Nov 29, 06: It was the first super predator of the ancient seas and its fearsome, jagged jaws still inspire awe 400 million years later. The armor-plated fish Dunkleosteus was a 10 meter-long, 3,600-kg monster that terrorized other marine life in the Devonian Period, which spanned 415 million to 360 million years ago. While lacking true teeth, Dunkleosteus used two long, bony blades in its mouth to snap and crush nearly any creature unfortunate enough to encounter it.
. . Scientists at the Field Museum in Chicago and the University of Chicago decided to test Dunkleosteus's reputation for wielding some of the most powerful jaws ever on Earth, creating a biomechanical model to simulate its jaws. They came away impressed. They said the big fish's bite packed 5,000 kgs of force.
. . The bony blades in its mouth, almost certainly enameled like teeth, concentrated the bite force into a small area at the tip at an astonishing force of 36,000 kg per square inch, they said. That, the scientists proclaimed, crowns Dunkleosteus as the all-time chomping champion of fish --sorry, sharks.
. . The researchers also determined that Dunkleosteus could open its mouth very rapidly --in a 50th of a second-- which formed a suction force drawing prey into the gaping mouth. It is very rare for a fish to possess both a powerful and a fast bite, they said.
. . Dunkleosteus appeared on Earth about 175 million years before the first dinosaurs and was one of the first jawed vertebrates. It hailed from a group of fish called placoderms, which bore heavy bony armor on the head and neck. This dominant predator ate just about anything it wanted. The menu included hard-shelled ammonoids with many tentacles, as well as other armored fish.

Nov 26, 06: The stellar baby boom period of the Milky Way sparked a flowering and crashing of life here on Earth, a new study suggests. Some 2.4 billion years ago, when the Milky Way started upping its star production, cosmic rays --high-speed atomic particles-- started pouring onto our planet, causing instability within the living. Populations of bacteria and algae repeatedly soared and crashed in the oceans.
. . Many sea creatures use carbon-13 to make their shells. If there is a lot of carbon-13 stored in rocks, it means life, the origin of which is still unknown, was booming. Therefore, variations in carbon-13 are a good indicator of the productivity of life on Earth. The researchers found that the biggest fluctuation in productivity coincided with star formation, which had an affect on Earth's climate and therefore on the productivity of life on our planet.
. . According to one theory, when a star explodes far away in the Milky Way, cosmic rays penetrate through the Earth's atmosphere and produce ions and free electrons. The released electrons act as catalysts and accelerate the formation of small clusters of sulfuric acid and water molecules, the building blocks of clouds. Therefore, cosmic rays increase cloud cover on Earth, reflecting sunlight and keeping the planet relatively cool.
. . Although cold and icy times are generally considered unfriendly to life, the data reveals that biological productivity kept oscillating between very high and very low. The reason, the researchers suggest, is that stronger winds during icy epochs stirred the oceans and improved the supply of nutrients in the surface waters.
. . "The odds are 10,000-to-1 against this unexpected link between cosmic rays and the variable state of the biosphere being just a coincidence, and it offers a new perspective on the connection between the evolution of the Milky Way and the entire history of life over the last 4 billion years", said study author Henrik Svensmark of the Danish National Space Center.

Nov 26, 06: Humpback whales have a type of brain cell seen only in humans, the great apes, and other cetaceans such as dolphins, U.S. researchers reported. This might mean such whales are more intelligent than they have been given credit for, and suggests the basis for complex brains either evolved more than once, or has gone unused by most species of animals, the researchers said.
. . The finding may help explain some of the behaviors seen in whales, such as intricate communication skills, the formation of alliances, cooperation, cultural transmission and tool usage.
. . They discovered a type of cell called a spindle neuron in the cortex, in areas comparable to where they are seen in humans and great apes. Although the function of spindle neurons is not well understood, they may be involved in cognition --learning, remembering and recognizing the world around oneself. Spindle cells may be affected by Alzheimer's disease and other debilitating brain disorders such as autism and schizophrenia.
. . The humpbacks also had structures that resembled "islands" in the cerebral cortex, also seen in some other mammals. These islands may have evolved in order to promote fast and efficient communication between neurons, the researchers said.
. . Spindle neurons probably first appeared in the common ancestor of hominids, humans and great apes about 15 million years ago, the researchers said --they are not seen in lesser apes or monkeys. In cetaceans, they would have evolved earlier, possibly as early as 30 million years ago, the researchers said. Either the spindle neurons were only kept in the animals with the largest brains or they evolved several times independently, the researchers said.
. . "In spite of the relative scarcity of information on many cetacean species, it is important to note in this context that sperm whales, killer whales, and certainly humpback whales, exhibit complex social patterns that included intricate communication skills, coalition-formation, cooperation, cultural transmission and tool usage", the researchers wrote.

Nov 23, 06: One person's DNA code can be as much as 10% different from another's, researchers said on Wednesday in a finding that questions the idea that everyone on Earth is 99.9% identical genetically.
. . Instead of showing single variations in human DNA that make people unique, the map looks at differences in duplications and deletions of large DNA segments known as copy number variants or CNVs, which can help explain why some people are susceptible to illnesses such as AIDS and others are not.
. . Scientists from more than a dozen centers around the world identified about 3,000 genes with variations in the number of copies of specific DNA segments. The changes can affect gene activity, including susceptibility to diseases. He said that resistance to infection by HIV, the virus that causes AIDS, is determined in part by multiple copies of the gene CCL3L1.
. . The CNV map gives researchers a different way to look for genes linked to diseases by identifying gains, losses and alterations in the genome. The consortium identified 1,447 different CNVs that covered about 12% of the human genome. About 285 of them are associated with diseases, including schizophrenia, psoriasis, coronary heart disease and congenital cataracts. Genes important to the immune system and to brain development and activity tend to have many CNVs, the researchers said. These are functions that have evolved rapidly in humans.

Nov 20, 06: Chimpanzee males prefer to have sex with older females, U.S. researchers found in a study that shows one of the biggest behavioral differences between humans and our closest biological relatives. Male chimps will chase down and fight over the oldest females, while the youngest female chimps are forced to beg for masculine attention.
. . "Chimpanzee copulations are frequently preceded by a series of male courtship signals (e.g., glancing with erect penis and branch shaking), after which either the male or the female approaches the other to mate", the researchers wrote. They also collected the chimps' urine to test for various hormones that demonstrate fertility.
. . They were checking to see if chimpanzees behave like humans, their closest living relatives, who form long-term mating bonds and who value younger females. This is most definitely not the case with chimps. The very oldest adult females were the most sought-after. "They don't have to do anything to get the males interested. The males find them. They follow them around. If you look at the very youngest females, the males will mate with them but it does take more work on the female's part."
. . Also unlike humans, female chimpanzees actively advertise when they are fertile, with bright red swellings around the genital area. And unlike human females, chimpanzees apparently remain fertile their entire lives, although these wild Ugandan chimpanzees rarely lived beyond the age of 40.

"The females that have access to the most food are the most fecund --the most likely to conceive in any cycle", he said. Males may know that.

Nov 20, 06: Like dogs mounting one another or rolling onto their backs, crayfish act out elaborate rituals of dominance and submission, U.S. researchers reported. They said it was the first time an invertebrate species had been seen to display such "humping" behavior, common in higher animals.
. . It appears to work, defusing tensions that might otherwise lead to a fight. "We found that crayfish display such a complex ritual, when two males engaged in pseudocopulatory behavior to signify their dominance relationship. This was followed by a reduction in aggression and an increased likelihood of the subordinate's survival." Lower-ranking crayfish that did not go along with another male's overtures were "killed, dismembered and partially eaten", the researchers wrote.
. . Crayfish, also commonly known as crawfish or crawdads, are commonly found at the bottoms of rivers, creeks and streams. They resemble small lobsters and are a considered a delicacy in many places.
. . The researchers said the findings in invertebrates showed such behavior was common in the animal world and may have evolved more than once over time. That suggests the behavior is useful for survival, the researchers wrote.

Nov 15, 06: Genetic material from the bone has let researchers identify more than a million building blocks of Neandertal DNA so far, and it should be enough to derive most of the creature's 3.3 billion blocks within the next two years, said researcher Svante Paabo.
. . "We're at the dawn of Neandertal genomics", said gene expert Edward Rubin of the Lawrence Berkeley National Laboratory. Only about one-seventh of an ounce or less of the bone will be enough to get a rough draft of the Neandertal genome.
. . Paabo's analysis didn't directly address whether modern humans have DNA from Neandertals, but it did raise speculation that DNA from anatomically modern humans might have found its way into Neandertals. Scientists will have to examine more Neandertal DNA to study that, he said.
. . Rubin also said analysis so far suggests human and Neandertal DNA are some 99.5% to nearly 99.9% identical.

Nov 15, 06: Researchers have sequenced DNA from the leg bone of a Neandertal man who died 38,000 years ago and said it shows the Neandertals are truly distant relatives of modern humans who interbred rarely, if at all, with our own immediate ancestors.
. . They estimate that modern humans and Neandertals split from a common ancestor at least 370,000 years ago, and possibly 500,000 years ago, although we share 99.95% of our DNA. "We see no evidence of mixing 40,000, 30,000 years ago in Europe. We don't exclude it, but see no evidence", Edward Rubin of the U.S. Department of Energy Joint Genome Institute, who led one study, told reporters. This conflicts with some evidence from other researchers, including a team who said earlier this month that humans may have inherited a brain gene from Neandertals.
. . Rubin's team used one method to isolate and sequence part of the Neandertal's DNA, while another team, led by Svante Paabo of the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, used a separate method to sequence a much larger amount.
. . Paabo was the first scientist to find and sequence Neandertal DNA, in 1997, and first suggested that Neandertals did not mix with modern humans. Neandertals and modern humans are both descended from Homo erectus, which left Africa and spread around the world about 1.5 million years ago.
. . The Neandertal sequences are 99.95% identical to human DNA sequences. This compares to about a 98% similarity between humans and chimpanzees, who split from a common ancestor 6 million to 7 million years ago.
. . Three-way comparisons among the human, chimpanzee and Neandertal genomes should shed light on what makes modern humans different, experts agreed. They found, for instance, sequences linked with eye color but cannot read the code to tell what color Neandertal eyes were.

Nov 8, 06: Neandertals may have given the modern humans who replaced them a priceless gift --a gene that helped them develop superior brains, U.S. researchers reported
. . Lahn's team found a brain gene that appears to have entered the human lineage about 1.1 million years ago, and that has a modern form, or allele, that appeared about 37,000 years ago --right before Neandertals became extinct.
. . "The gene microcephalin (MCPH1) regulates brain size during development and has experienced positive selection in the lineage leading to Homo sapiens", the researchers wrote. Positive selection means the gene conferred some sort of advantage, so that people who had it were more likely to have descendants than people who did not. Lahn's team estimated that 70% of all living humans have this type D variant of the gene.
. . "By no means do these findings constitute definitive proof that a Neandertal was the source of the original copy of the D allele. However, our evidence shows that it is one of the best candidates", Lahn said.
. . The researchers reached their conclusions by doing a statistical analysis of the DNA sequence of microcephalin, which is known to play a role in regulating brain size in humans. Mutations in the human gene cause development of a much smaller brain, a condition called microcephaly.
. . They noted that this D allele is very common in Europe, where Neandertals lived, and more rare in Africa, where they did not. Lahn said it is not yet clear what advantage the D allele gives the human brain. "The D alleles may not even change brain size; they may only make the brain a bit more efficient if it indeed affects brain function", Lahn said. [tho there is much doubt that the species could interbreed at all...]

Nov 8, 06: Tarantulas and chili peppers may not appear to have anything in common but an encounter with either the spider or the plant can be a painful experience. Scientists at the U of California, San Francisco have discovered that they use similar tactics to frighten off predators by causing pain. Capsaicin, the main pungent ingredient in hot chili peppers, sets it off.
. . The venom of tarantula Psalmopoeus cambridgei, which is a native species in Trinidad and Tobago, contains toxins that trigger the same pain receptor on nerve cells throughout the body as hot chili peppers.

Nov 8, 06: Sea urchins may be blind, but they have the same genes that help people see, as well as genes for a sense of smell and one of the most complicated immune systems in the animal world, researchers reported.

Nov 7, 06: Pigeons and baboons have a remarkably good long-term memory, according to a study. Two male 18-year-old baboons and two Silver King pigeons were placed in front of computers and were shown pictures. They had to peck --in the case of the monkeys, using a joystick-- a cross or a circle to show whether or not they had seen the image before.
. . Over five years, birds Linus and BF memorized 800 to 1,200 different pictures before reaching their limit. The baboons, more prosaically called No. 3 and No. 9, had memorised 3,500 to 5,000 pictures and had not yet reached a limit by the end of the study. The two species demonstrated similar memory-loss rates and reaction times and only differed in their memory capacity.
. . Memory capacity was probably shaped powerfully by evolution and was probably key to the rise of intelligence in humans, the authors suggest.

Nov 6, 06: Billions of years ago, Earth may have been shrouded in a blanket of atmospheric haze like that seen on Saturn's moon Titan, providing organic material that nourished our planet's earliest life forms, researchers said. Some scientists look to Titan as a model for what early Earth's atmosphere may have looked like. They think Titan's atmosphere, packed with organic aerosol particles created when sunlight reacts with methane gas, may offer clues about Earth's climate when primitive organisms were first arising 3.6 billion years ago.
. . U of Colorado scientist Margaret Tolbert and her colleagues conducted laboratory experiments. They irradiated methane gas with an ultraviolet lamp, then mixed in CO2 to see whether conditions that may have existed eons ago on Earth could yield a comparable organic haze. They found that such a haze formed in the lab using various methane and CO2 concentrations.
. . Tolbert said the chemical composition of the haze was organic molecules that are digestible to organisms alive today and could have nourished simple living organisms along ago. Scientists previously have concentrated on isolated, extreme environments such as hydrothermal vents bursting with energy and nutrients to understand primordial life. Beyond merely providing a food source for early life forms, this organic haze also may have played a role in providing the very building blocks needed for living organisms to first form, Tolbert said.
. . Earth was formed perhaps 4.6 billion years ago, and liquid water was present about 3.8 billion years ago. Tolbert said this haze may have been a dominant feature of Earth's early atmospheric landscape from about the time of the first evidence of life 3.6 billion years ago until the rise of the oxygen content about 2.3 billion years ago.
. . The thick haze not only may have nourished organisms, but may have protected them from harmful ultraviolet rays. The haze may have placed more than 100 million metric tons of organic material on Earth's surface annually, the study estimated.

Nov 5, 06: Japanese researchers said that a bottlenose dolphin captured last month has an extra set of fins that could be the remains of hind legs, a discovery that may provide further evidence that ocean-dwelling mammals once lived on land. Fishermen captured the four-finned dolphin alive off the coast of Wakayama prefecture (state) in western Japan on Oct. 28, and alerted the nearby Taiji Whaling Museum.
. . Fossil remains show dolphins and whales were four-footed land animals about 50 million years ago and share the same common ancestor as hippos and deer. Whale and dolphin fetuses also show signs of hind protrusions but these generally disappear before birth. Though odd-shaped protrusions have been found near the tails of dolphins and whales captured in the past, researchers say this was the first time one had been found with well-developed, symmetrical fins.
. . The second set of fins —-much smaller than the dolphin's front fins-— are about the size of human hands and protrude from near the tail on the dolphin's underside. A freak mutation may have caused the ancient trait to reassert itself.
. . It will undergo X-ray and DNA tests.

Nov 3, 06: Politics may not be in the blood, but it could be in the genes. That's the theory a team of political scientists and geneticists is trying to prove with extensive studies of twins, genes and brain scans.
. . The idea goes back more than 2000 years. In 350 B.C., Aristotle wrote, "Man is by nature a political animal."
. . Now, Alford said, scientists are trying to improve on that. Genetic researchers are trying to prove that social attitudes can be inherited, and have discovered strong correlations between the two. So far, the political connection has relied on studies by Lindon Eaves, professor of human genetics and psychiatry at Virginia Commonwealth University. About 8,000 sets of identical and fraternal twins answered a series of questions on topics such as school prayer, nuclear power, women's liberation and the death penalty.
. . Identical twins, who share their entire genetic code, answered more similarly than fraternal twins, who are no more similar than non-twin siblings. If you assume that both identical and fraternal twins share an environment, then the disparity between the results must be genetic, Hibbing and colleagues conclude.
. . Some scientists, however, are not ready to embrace the theory. "The very idea that something like a political ideology could be heritable is incoherent", said Evan Charney, assistant professor of public policy and political science at Duke University. "It doesn't make any sense, and it's historically inaccurate." Any similarities found in twins' political beliefs can be attributed to environment, not genetics, Charney said.

Oct 31, 06: Paleontologists re-examined tracks left by therapods --carnivorous bipedal dinosaurs such as Tyrannosaurus rex. Dinosaur bones from the Middle Jurassic are rare in North America, making it hard to match these footprints with any particular species. Based on the length of their strides, these dinosaurs were roughly the size of humans.
. . Mysteriously, sometimes the dinosaur tracks are crossed --that is, the right foot crossed over the left, or vice versa. To solve this puzzle, researcher Brent Breithaupt, curator and director of the University of Wyoming's Geological Museum in Laramie, Wyo., and his colleagues hunted for modern animals that walked in similar ways.
. . Large flightless birds are the most logical choice to study because evidence suggests that they, along with all birds, are descended from dinosaurs. They are also roughly the size of humans, bipedal, and their legs are kept relatively close together.
. . Ostriches have an attitude problem and are two-toed, unlike therapods, which had three-toed feet. Emus have three toes and are relatively easy to study. The emus, whose feet are not splayed very wide apart, often looked around as they walked, frequently creating crossed tracks.
. . It also appears that the dinosaurs may have traveled in family groups, since there are juvenile and adult tracks. That could suggest some sort of parental care, Breithaupt said, or at the very least support the idea that the dinosaurs were social animals, just like modern birds.

Elephants can recognize themselves in a mirror, joining only humans, apes and dolphins as animals that possess this kind of self-awareness, researchers now report.
. . A 34-year-old female Asian elephant in the Bronx Zoo showed researchers that pachyderms can recognize themselves in a mirror —-complex behavior observed in only a few other species. The test results suggest elephants —-or at least Happy-— are self-aware. The ability to distinguish oneself from others had been shown only in humans, chimpanzees and, to a limited extent, dolphins.
. . That self-recognition may underlie the social complexity seen in elephants, and could be linked to the empathy and altruism that the big-brained animals have been known to display, said researcher Diana Reiss, of the Wildlife Conservation Society, which manages the Bronx Zoo.
. . In a 2005 experiment, Happy faced her reflection in an 8-by-8-foot mirror and repeatedly used her trunk to touch an "X" painted above her eye. The elephant could not have seen the mark except in her reflection. "It seems to verify for us she definitely recognized herself in the mirror." Maxine, for instance, used the tip of her trunk to probe the inside of her mouth while facing the mirror. She also used her trunk to slowly pull one ear toward the mirror, as if she were using the reflection to investigate herself. The researchers reported not seeing that type of behavior at any other time.
. . The three Bronx Zoo elephants did not display any social behavior in front of the mirror, suggesting that each recognized the reflected image as itself and not another elephant. Many other animals mistake their mirror reflections for other creatures.

Oct 31, 06: Anthropologists have long wondered what happened when the two species met as modern humans spread from Africa into Neandertal territory in Eurasia: did the populations interbreed or did modern humans simply replace their cousins?
. . The specimens examined and dated for the first time in this study show that "at least in Europe, the populations blended", said study author Erik Trinkaus of Washington University.
. . The study compared the fragments, including a skull and jaw, to bones of Neandertals, early modern humans in Africa before they spread, and in Europe afterward. Trinkaus said that he and his colleagues found certain features that could have only come from Neandertals, because early modern humans lost them before they spread from Africa.
. . They found a swelling at the back of skull, called an occipital bun, which is the result of differential brain growth and is commonly found in Neandertal skulls. Also, the arrangement of muscle attachment at the back of the jaw was a trait of Neandertals.
. . When the remains were discovered in a Romanian cave in the early 1950s, prior to carbon dating, they were not embedded in a rock layer that might indicate their age. Because the bones essentially looked like those of an early modern human, they received little attention inside Romania and were unknown outside the country.
. . Some scientists dispute that there was any overlap between the two species. DNA tests seem to show no mixing.

Oct 30, 06: Could the human species split in two over time due to evolutionary pressures as predicted by science fiction writer H.G. Wells? Evolutionary theorist Oliver Curry of the London School of Economics believes it could happen in 100,000 years.
. . Curry believes that the near-term descendants of the genetic upper class will be tall, slim, healthy, attractive, intelligent and creative. "Underclass" human beings will have devolved into dim-witted, short, goblin-like creatures.
. . Further down the road, upper class humans will pay a price for reliance on technology. Spoiled by technology that will do everything for them, humans could come to resemble "domesticated animals." Chins would recede, as a result of chewing on carefully processed foods. Reliance on medicine would result in weakened immune systems, with genetic weaknesses no longer thrown out of the gene pool. The logical outcome, says Curry, would be two sub-species of human beings; one group gracile (slim and attractive) and the other more robust and physically strong.
. . Frankly, you can get all this along with a much better story line and a more coherent narrative if you read H.G. Wells' "The Time Machine", his 1898 classic on the future.

Scientists have identified the oldest known bee, a 100 million-year-old specimen preserved in amber. The discovery coincides with the publication of the genetic blueprint of the honeybee, which reveals surprising links with mammals and humans.
. . The ancient insect, trapped in tree sap, is at least 35-45 million years older than any other known bee fossil. It appears to share features with both bees and wasps, and supports theories of bee evolution. Experts believe pollen-dependent bees arose from carnivorous wasp ancestors. With the arrival of pollinating bees, flowering plants blossomed on Earth. Prior to 100 million years ago, the plant world was dominated by conifers which spread their seeds on the wind.
. . "But overall it's more bee than wasp, and gives us a pretty good idea of when these two types of insects were separating on their evolutionary paths." It has waspish features, such as narrow hind legs, but also branched body hair and other characteristics of bees.
. . The fossil bee is in remarkable condition, with individual hairs preserved on undamaged portions of thorax, legs, abdomen and head. Legs and wings are also clearly visible. It is tiny, measuring barely 3mm across. This is consistent with evidence that some of the earliest flowers were also small.
. . There are now around 20,000 species of bees, which use pollen to feed their young.

Oct 26, 06: By looking at variations in genetic markers from 341 bees, researchers found that the common honey bee, Apis mellifera, originated in Africa and migrated to Europe at least twice. "The migrations resulted in two European populations that are geographically close, but genetically quite different."

Oct 25, 06: Honey bees have an internal "biological clock" which is more like those of mammals than of flies, the research has revealed. The clock governs many activities, including time sensing, navigation, labour division, and the famous bee "dance language".
. . Another group of scientists from the University of Illinois found 36 genes in the honey bee brain, 33 of which were previously unreported. They coded for 100 neuropeptides --organic molecules that control brain activity in both bees and humans, the researchers report. In the bee brain, which is not much larger than a full stop, they help to regulate around one million neurons.

Oct 25, 06: Scientists have unraveled the genetic code of the honey bee, uncovering clues about its complex social behavior, heightened sense of smell and African origins. It is the third insect to have its genome mapped and joins the fruit fly and mosquito. The honey bee, or Apis mellifera, evolved more slowly than the other insects but has more genes related to smell. The honey bee genome could also improve the search for genes linked to social behavior.
. . The queen has 10 times the lifespan of workers and lays up to 2,000 eggs a day. Despite having tiny brains, honey bees display honed cognitive abilities and learn to associate a flower's color, shape and scent with food, which increases its foraging ability.
. . The scientists discovered the honey bee originated in Africa and spread to Europe in two ancient migrations.
. . The number of genes in honey bees related to smell outnumber those linked to taste. The insects also have fewer genes than the fruitfly or mosquito for immunity. Honey bees use pheromones, substances secreted by glands, to distinguish the gender, caste and age of other bees, according to the scientists.

Oct 24, 06: They may have ruled the land and the seas 75 million years ago, but even dinosaurs fell prey to the lowest of the low --gut worms, scientists reported. [The foor chain is a circle.]
. . An unusually well-preserved fossil of a duck-billed dinosaur dug up in Montana has revealed great detail of the animal's insides, including what appear to be tiny burrows that would have been made by worms. They found more than 200 suspected parasite burrows that most likely were made by tiny worms similar to annelids and nematodes that infest animals today. "Since the carcass was apparently buried before it had a chance to fall apart, we think remnant parasites may have been living inside of the animal when it died."
. . Duck-billed dinosaurs were plant-eaters, reaching up to 50 feet long and weighing up to three tons.

Oct 23, 06: After surviving the ice age, parasites and insecticides, French honey bees are now under threat from placid foreigners. Apis Mellifera Mellifera, the native subspecies also known as the dark bee, is losing out to central and eastern European breeds because beekeepers find them easier to handle and less likely to sting.
. . The dark bee makes up around 75% of stocks in France after being totally dominant in the late 1980s. "But I don't think its survival is threatened --we are only talking about certain honey-producing regions and the dark bee does rather well on its own in nature."
. . Raymond Borneck disagrees. A former head of beekeeping professional and technical associations whose career dates back to 1946, Borneck says the dark bees' future is "more or less a lost cause."

Oct 19, 06: A primitive fish that swam in tropical reef systems before life clambered up on land had more advanced features than previously thought, a new study finds.
. . Scientists led by John Long of the Museum Victoria in Melbourne, Australia, discovered the first complete fossil of a Gogonasus fish last year in a limestone formation in Western Australia. Prior to the new discovery, only parts of Gogonasus, including a snout and part of a skull, had been found.
. . The newly discovered fossil "has all these remarkable details preserved that none of the other specimens could show", Long said. The specimen, whose middle ear and limbs resemble those of land vertebrates, could be one of the missing links between fish and four-legged land vertebrates, bringing researchers closer to the point when life reached the water's edge. Gogonasus was an ambush predator, about .4meter long, that trolled tropical reefs during the Devonian period or the "Age of Fishes."
. . When the scientists unearthed the Gogo fossil, they could still open and close its mouth. "It's like it died yesterday", Long said. With a computed tomography (CT) machine, which beams X-rays at hundreds of different angles around an object one slice at a time, the scientists created three-dimensional images of the skeleton. The fish had a big hole in its head. Called a spiracle opening, the cavity leads down into the gill chamber used for breathing and is thought to be the forerunner for the middle ear in modern land animals.
. . The fossil also showed the beginnings of a wrist joint and a complete front fin, consisting of the same arm bones found in humans and four-legged animals--the humerus, radius and ulna. The scientists suspect the fish used the front limb to push off the sea bottom and lunge at prey. "So it could've rested on those fins and then just pushed off. I think rather than walking on land, it was using this to push itself out of the reef to catch prey", Long said. "The fins needed to be strong and muscular, because the thrust was coming from the front of the animal and not from the tail."
. . The scientists think the findings will lead to a re-shuffling of the evolutionary line-up of fish from the earliest fish to land animals, placing Gogonasus closer to tetrapods than Eusthenopteron, a fish with tetrapod features.

Oct 18, 06: The faces we pull when we are happy, sad or angry may be passed from generation to generation, according to researchers. They said their findings suggested expressions may be hereditary.
. . An Israeli team discovered facial expressions among family members bore striking similarities. This confirms an idea posed by Charles Darwin in 1872. In his famous work, The Expression of the Emotions in Man and Animals, he suggested facial expressions were innate.
. . To test this, University of Haifa researchers analysed the facial expressions of 21 volunteers who had been blind from birth along with those of their relatives. They interviewed the participants, asking them to recount experiences of when they were happy, sad, angry and disgusted, and recorded their mannerisms while doing so. They also set them a test to see what they looked like when they were concentrating, and shocked them to witness their expressions of surprise.
. . When the researchers compared the results, they discovered that even though the blind volunteers had never seen their relatives' faces before, their facial expressions were extremely alike. The strongest correlation was for the negative emotions.
. . She said her results suggested that facial expressions were inherited and therefore had an evolutionary basis. "Our next step is to find the exact genes that influence facial expression." This, she added, could have an impact on autism research, where facial expressions are central to the disorder.
. . Professor Ruth Mace, an evolutionary anthropologist from University College London, UK, said: "We have known that expressing your emotions is something that has been molded by natural selection for a long time. "As a social species, it makes sense for us to be able to read each others' emotions to predict how they are going to behave and how they are going to respond. "It is all part of being social and living in groups. Being able to read people's faces is very important and it makes sense that there is a hereditary component."

Oct 18, 06: A prehistoric sea reptile propelled itself with fins reinforced by a fiberglass-like mesh, a new study finds. In fiberglass, thin strands of glass are mixed with plastic to provide strength. The toughened material, which can be molded into any shape, is commonly used in light-body cars, airplanes and boats.
. . Researchers recently discovered that a similar mesh covered the fins of Ichthyosaurs, a fish-like marine reptile that lived during the age of dinosaurs. Instead of glass, though, their fins were coated with the protein collagen. Present in animal bone and connective tissues, this fibrous protein helps give skin its elasticity, and its breakdown with age causes wrinkles.
. . Stiff fins and a streamlined body shape also evolved in fast-swimming tuna, dolphins and sharks. In a previous study, Lingham-Soliar showed that a great white shark's skin contains large amounts of collagen, arranged in sheets that lie at slightly different angles to one another --an arrangement virtually identical to that found in Stenopterygius' fins. In the great white, the collagen mesh enveloped the animal's entire body, but it was thicker around the tail and dorsal fins. Tuna also have stiff dorsal and tail fins, but their fins are supported by bony spines.
. . Early Ichthyosaurs were serpentine, and looked like snakes with fins, but their bodies gradually became more streamlined and fish-shaped as they evolved. Later species resembled hunchbacked dolphins, and even had dorsal fins on their backs.
. . Ichthyosaurs first appeared about 250 million years ago, slightly earlier than dinosaurs, and disappeared just before them.. They ranged in length from .7meters to more than 13 meters, but most were almost 3meters long. At their peak abundance during the Jurassic, they were the ocean's top predators.

Oct 17, 06: The bones of an extinct species of pygmy water buffalo that once lived in the Philippines has been discovered -—thanks to people's need to do household chores. Filipino mining engineer Michael Armas found an unusual set of fossils about 40 years ago as he was excavating a hillside on the island of Cebu looking for phosphate, a naturally occurring compound used in detergents and fertilizers. He took the fossils home with him, where they sat in a jar for several years.
. . The bones, the scientists found, belonged to a species of water buffalo that probably lived between 10,000 and 100,000 years ago. The tiny bovine stood up to 0.7 meter tall and weighed about 160 kg.
. . The extinct creatures were similar to a modern species of small water buffalo that lives on the nearby Philippines island of Mindoro. That animal reaches 0.9 meter tall. It is related to the Asian water buffalo --an even larger modern species that stands 1.8 meters tall and can weigh up to a ton. "Only a few fossils of elephants, rhinos, pig, and deer have been found here previously."
. . It could offer insight into a phenomenon called island dwarfing, a process in which large species confined to isolated islands tend to grow smaller due to fewer resources. Island dwarfing is one of the competing explanations for the famous "hobbit" human fossils found in 2003 on the Philippines island of Flores. The fossils represent a distinct species of human that stood only 1 meter tall and lived at the same time as modern humans, some 13,000 years ago, the hobbits' discoverers say.

Oct 14, 06: Often in life, fate depends on which family one is born into. Baby finches with ugly fathers lose out on the good genes and get little food brought home by dad. So Mom has developed a clever coping strategy to compensate for this nutritional deficit, a new study finds.
. . Male house finches range from bright red to drab yellow. The color of their plumage is a result of dietary pigments called cartenoids, which are consumed in the wild. Coloring is therefore a good indicator of a male finch’s foraging abilities. "The males that are better foragers are able to ingest more carotenoids, and thus their plumage is red." Redder males have also been shown to feed females and offspring more, making them more attractive as potential fathers.
. . Because chicks that are sired by ugly fathers are not fed as much, they could suffer from nutritional deficit. Therefore, female house finches deposit more antioxidants, including 2.5 times more vitamin E, into the yolks of the eggs sired by unattractive males. This protects the embryo during the developmental process. The antioxidants are thought to stimulate the immune system and protect against reactive atoms or molecules that can damage proteins in the body.

Oct 12, 06: The exact moment when a 550 million year old cell began to divide has been captured in an exquisite 3-D image. The specimens are the oldest known examples of fossil embryos, and shed light on the early evolution of complex life.
. . A limestone bed deposited between 635 and 551 million years ago contains layers composed almost entirely of fossil embryos. The team behind the research believe the fossils are the developing offspring of extremely primitive sponge-like creatures.
. . To resolve the delicate internal structures, the scientists used a technique known as microfocus x-ray computed tomography (microCT). Inside, the team found kidney-shaped structures which they believe could be nuclei or other subcellular components. "It is amazing that such delicate biological structures can be preserved in such an ancient deposit", said Professor Xiao. In some four-celled embryos, each cell had two of the kidney-shaped structures, suggesting they were caught in the process of splitting prior to cell division. If true, this would suggest that complex multi-cellular life got started much earlier than previously thought, prior to the "Cambrian Explosion" 542 million years ago. At that time, fossils record a dramatic change in animal diversity with many of today's modern groups suddenly making an appearance.
. . Although the cells show some modern traits, they crucially lack others. "Even in these late-stage embryos, there is no evidence of the formation of a tissue layer", said Dr Donoghue. "You would expect to see that in modern embryos, even those of sponges." The team believes the cells probably came from extremely simple creatures.
. . Previous research has suggested that the embryos were the product of complex animals, the ancestors of modern organisms.

Oct 12, 06: Paabo had been thinking about how to identify genes that had changed during human evolution to make speech possible, and FOXP2 seemed like a prime candidate. He and his co-workers sequenced the gene—that is, they figured out the order of the DNA bases that make up FOXP2—in six different species. They found that it was one of the most stable genes they had ever studied; from mice to rhesus macaques to chimps, the protein produced by the gene is almost exactly identical, suggesting that the gene itself plays a fundamental role in animal function. But in humans the gene had undergone a slight modification. About 250,000 years ago, according to the scientists' calculations, two of the molecular units in the 715-unit DNA sequence of the gene abruptly changed. That's not long before modern humans first appeared in the fossil record. Could the changes in FOXP2 have enabled modern humans to speak? And could articulate speech have given modern humans an edge over the Neanderthals and other archaic humans?
. . Researchers are genetically engineering mice with "broken" FOXP2 genes, to see how disruptions in the gene might affect the animals. Also, researchers are splicing the human version of the gene into mice to see if it makes any difference. (So far, none of the mice have started talking.)
. . The ultimate goal of his research, Paabo says, is to identify the genetic changes that made us human. Of course, no historical event can ever be reconstructed completely. But by studying our DNA, scientists eventually will be able to say which genes changed, when they changed, and maybe even why they changed. At that point, we'll have something we've never had before: a scientifically plausible and relatively complete story of our biological origins.

Oct 11, 06: Giant insects might crawl on Earth or fly above it if there was just more oxygen in the air, scientists report.
. . Roughly 300 million years ago, giant insects scuttled around and fluttered over the planet, with dragonflies bearing wingspans comparable to hawks at two-and-a-half feet. Back then, oxygen made up 35% of the air, compared to the 21% we breathe now. Not all the insects back then were giants, but still, "maybe 10% were."
. . Eventually, tracheae cannot develop beyond a certain size. Based on their calculations, the researchers figure modern beetles cannot grow larger than about six inches. This happens to be about the size of the largest beetle known—the Titanic longhorn beetle, Titanus giganteus, from South America, Kaiser said.
. . If the atmosphere in the past held more oxygen, tracheae could be narrower and still deliver enough oxygen for a much larger insect. This would lead to a much larger size limit, Kaiser concluded.

Oct 10, 06: The horns of adult Triceratops grew almost a meter long and the forward curvature marked their owners as sexually mature, the researchers speculate.
. . Triceratops' bony frill changed [image] with age as well. In juveniles, the frill edge was adorned with triangular bones resembling arrowheads. The spiky edges flatten as the animal aged and were barely visible in adults.
. . It was once thought Triceratops used its horns as weapons against predators like Tyrannosaurus rex. But most paleontologists now agree that the elaborate adornments of many dinosaurs -—Triceratops' horns, the bony plates of Stegosaurus and the odd head crests of duck-billed dinosaurs—- were used for species recognition or mate attraction, much like colorful feathers in birds.

Oct 9, 06: They wouldn't win any beauty contests, but naked mole-rats would take home the crown for longevity. And research into human aging might draw from knowledge of the wrinkly subterranean creatures. [ They're rats, not moles.]
. . No bigger than a stick of butter, mole-rats long outlive similar-sized rodents. They're known to approach age 30. Now scientists have gained some insight into this longevity: Mole-rats simply deal with the kind of cellular damage that life normally brings about.
. . "The naked mole-rat, with its surprisingly long life span and remarkably delayed aging, seems like the perfect model to provide answers about how we age and how to retard the aging process", said Rochelle Buffenstein of the City College of New York. "This animal may one day provide the clues to how we can significantly extend life."
. . Mole-rat Oddities:
. * They almost never go above ground and are nearly blind.
. * They dig out burrows with oversized buckteeth.
. * They live in colonies of up to 300 individuals, with one breeding female, similar to a queen bee.
. * Within their tunneling burrows, they delineate a separate toilet area, where feces and urine get stored.
. * They farm underground tubers by feeding from one end, plugging the end with soil and then feeding from the tuber’s other end.

Oct 4, 06: The jumping of a gene from one chromosome to another can likely contribute to the birth of new species, a genetic analysis of flies reveals. The result validates an underappreciated mechanism of so-called reproductive isolation, a key component of speciation.
. . According to the National Academy of Sciences (NAS), a scientific theory is "a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses." No amount of validation changes a theory into a law, which is a descriptive generalization about nature. So when scientists talk about the theory of evolution--or the atomic theory or the theory of relativity, for that matter--they are not expressing reservations about its truth.

Oct 4, 06: A viral gene embedded in the sheep genome plays an essential role in the growth of the animal's placenta, according to a study of impregnated sheep. The result strengthens the case that similar viral genes play the same role in mice and people.
. . Up to 10% of a mammal's genome is made up of DNA captured from retroviruses, which insert their DNA into the host genome and sometimes lose the ability to get back out of the cell. Most of this genetic material seems to be gibberish, but in humans there are signs that one viral gene is still kicking. Genetic studies of post-birth placentas spotted activity from a gene that would once have produced part of the protein envelope coating a circulating retrovirus, now extinct. Researchers identified envelope genes from other viruses active in the placentas of mice, primates and sheep. The viral gene products cause cultured cells to fuse together as they would in the placenta, suggesting they play a considerable reproductive role in these various mammals.

Oct 4, 06: To help make up for sleep lost during marathon night flights, migratory birds take hundreds of powernaps during the day, each lasting only a few seconds, a new study suggests.
. . Every autumn, Swainson's thrushes fly up to 3,000 miles from their breeding grounds in northern Canada and Alaska to winter in Central and South America. Come spring, the birds make the long trek back. The birds fly mostly at night and often for long hours at a time, leaving little time for sleep when they do stop.
. . To find out how the birds get through these tiresome periods, scientists observed caged thrushes for an entire year, recording when and how long they slept. They found that during autumn and spring, when the birds are normally migrating, they reverse their typical sleep patterns, staying awake at night and resting during day. But instead of sleeping for long stretches at a time, the birds took several naps a day, each one lasting only 9 seconds on average.
. . The thrushes also mixed up their shut-eye sessions with two other forms of sleep. In one, called unilateral eye closure, or UEC, the birds rested one eye and one half of their brains while their other eye and brain hemisphere remained open and active, keeping them semi-alert to danger.
. . The birds also occasionally slipped into another state, one that any college student who has ever been stuck in a boring lecture can relate to. Called drowsiness, this state is characterized by a partial shutting of both eyes that still allows for some visual processing.
. . Some scientists speculate that some birds might even be able to catch up on some forms of sleep while in flight, but this idea has yet to be fully tested.

Oct 3, 06: Croatian scientists have worked out how a radiation-resistant bacterium that can exist in extreme conditions repairs damage to itself, a discovery which could provide clues about diseases such as cancer.
. . The organism called Deinococcus radiodurans is so hardy it can survive ionizing radiation 5,000 times stronger than the level lethal to humans. "Through evolution, the bacteria have developed a mechanism to precisely reconstruct its DNA. Until now this has been a scientific riddle."
. . Many diseases including cancer involve alterations to DNA and an inability to recover from the damage.

Oct 2, 06: When threatened, minnows bunch together, swim slower and make quick darting movements to fake out their predators. How close they group together and how often they dart depends on the level of the threat. But sometimes vision isn't enough to tell the minnows these things, so the small fish rely on another tactic: They sniff the water for scents of their predators.
. . A new study, detailed in the October issue of the journal Animal Behavior, reveals that a minnow's sense of smell is so sophisticated that it can pick out the odor of a single predator pike fish among many. The discovery adds to a long list of amazing animal senses that make humans seem woefully unaware of their surroundings by comparison.
. . When the skin of a minnow is torn open, unique chemicals are released that put other minnows on high-alert. They learn to associate both the smell of broken minnow-flesh and the odor of predator pikes with danger. But where Pavlov's dogs required numerous trials before the connection between bell and food finally clicked, minnows require only a single predator exposure and the lesson is learned for life.

Sept 30, 06: Arctic whales whose long, spiraled tusks created the myth of the unicorn seem to call out with individual voices, according to a new study. Researchers think the vocalizations help narwhals to recognize each other or reunite with distant pods, just as our relatives can identify us over the phone, for instance.
. . Scientists have known that marine mammals rely on acoustic signaling for underwater communication. Whales speak in dialects, a recent study found. But few studies have looked at individual animal voices.
. . The spy tags from two of the narwhals revealed two individually-distinctive vocalizations, including whistle and pulsed sounds. Shapiro suggested both the whistles, which have been shown to identify individual dolphins, and pulsed signals did not relate to foraging for food but rather to social communication.

Sept 28, 06: The length of a girl's ring finger could be an indicator of her future sporting potential, researchers at King's College London said today. In the largest study of its kind, hand measurements of 607 female twins aged 25-79 from the UK were compared with the women's lifetime sporting achievements.
. . The findings were that women with ring fingers longer than their index fingers had performed better at running and associated running sports such as soccer and tennis. In women, the ring finger is commonly shorter or the same length as the index finger, while in men the ring finger is generally longer.
. . "Previous studies have suggested the change in finger length was due to changes in testosterone levels in the womb," he said. But he said the unit had found in a separate study of twins that finger length was largely inherited, possibly explaining why sporting parents often have sporting children.

Sept 27, 06: Tarantulas can produce silk from spigots on their feet as well as from their abdominal spinnerets, a finding that could help explain why spiders began to spin silk in the first place, researchers said. The foot silk appears to help keep the spiders from sliding on slippery surfaces.
. . "If we find that other spiders in addition to these tarantulas have the ability to secrete silk from their feet, this could represent a major change in our evolutionary hypothesis regarding spider silk", Summers said. "It could mean that silk production actually originated in the feet to increase traction, with the diversity of spinneret silk evolving later." The spinneret is the organ in a spider that produces the thread for webs.
. . They said they were making the furry, striped spiders walk on vertical plates of glass to see how they used hairs and small claws on their feet to cling. When the spiders started to slip, the researchers were surprised to see them start to produce fluid from their feet. It was silk. Summers' team used scanning electron microscopy to examine the spiders' legs and found openings that resemble the spigots on the spinnerets in the abdomens of the spiders.

Sept 27, 06: Just as siblings may scuffle over who gets the front seat or access to the TV remote control, some bird siblings jostle for position in their nests. Those with winning moves can sit in the spot where mom is most likely to deliver food.
. . For Alpine Swift birds, which build nests on tall buildings or holes in cliffs, this sibling rivalry can also mean a nasty fall from the nest. A new study found the more crowded the nest the more likely nestlings would battle with siblings and risk a lethal fall.

Sept 27, 06: Paleontologists from Montana and Mongolia, who want to flesh out the developmental biology of dinosaurs, recently found 67 dinosaur skeletons in the Gobi Desert in just one week.
. . Jack Horner, a Montana State University paleontologist, said the skeletons were of a particular dinosaur—Psittacosaurus, or “parrot lizard” -—a plant-eater that lived about 120 million years ago, and was an ancestor of horned dinosaurs like the Triceratops.
. . Psittacosaurus isn’t a new species, but is very common and provides paleontologists with lots of specimens, which is precisely what this team wanted. By examining a large number of fossils, Horner can compare variations between skeletons of the same species and observe changes during the growth of the beasts from youth to old age.

Sept 26, 06: Scientists have mapped every gene in the mouse brain as part of Paul Allen's Brain Atlas project launched in 2001. While brain maps until now have been similar to a traditional encyclopedia, the Allen Brain Atlas is more like Google Earth.
. . When the Microsoft co-founder donated $100 million for the project, his stipulations were that the map be open access and free. The brain atlas combines cellular-resolution scans of the mouse brain with precise information about which genes are expressed where. "We have essentially mapped each individual gene in the mouse brain, about 21,000 genes in all, down to the cellular level", said Allan Jones, chief scientific officer at the Allen Institute for Brain Science.
. . The brains of mice and men are not genetically identical, however --tiny differences produce very different brains. For this reason, the institute's next project will map human brain samples in an effort to better understand human neurological health and disease.
. . From these data, we have determined that about 80% of all genes are turned on somewhere in the brain. Before, scientists generally thought that number was closer to 60 or 70%."

Sept 25, 06: Like any protective mother, female house finches try to keep their chicks away from unwanted pests. But they favor their more vulnerable sons over their sturdier daughters, according to a new study.
. . Blood-sucking mites can infest a finch's nest, jeopardizing the chicks' chances of surviving long enough to leave home. And, "sons are more sensitive to the mites than daughters."
. . When breeding female finches are exposed to the mites, their bodies make hormonal changes that help out their more susceptible sons. When a female finch lays eggs, she lays only one per day. The hormone shifts in her body change the order in which eggs are laid—girls first, boys last—and make the male chicks grow faster while they're still in the egg. "Mothers essentially hid their sons in the eggs."
. . Because they have less exposure to the mites, the male chicks born during mite season can grow up just as big and strong as those born during mite-free months, even though they spend less time in the nest, the study concluded.

Sept 25, 06: A dinosaur species long accused of cannibalism and infanticide is finally having the charges against it dropped and its reputation restored.
. . Researchers re-examining the anatomy of a Coelophysis fossil at the American Museum of Natural History (AMNH) found that bones in the rib-cage of the small upright dinosaur are not of its own kind, but of a primitive crocodile.
. . In a separate example, it was shown that the remains of a juvenile Coelophysis were actually located outside of another adult. The adult dinosaur probably crushed the juvenile when it died, the researchers say, and when the flesh decayed, the overlapping bones created the illusion that one dinosaur ate the other.

Sept 25, 06: A researcher who specializes in multiple-birth pregnancies has confirmed that taller women are more likely to have twins.
. . Taller women have more of an insulin-like growth factor that has been linked to height and to the rate of twins in previous work. Dr. Gary Steinman, an obstetrician at Long Island Jewish Medical Center, compared heights of 125 women who had twins and 24 who had triplets to the average height of U.S. women. Those who birthed two or more children were on average more than an inch taller. Countries with taller women have higher rates of twinning.
. . In a previous study, Steinman found that women who consume animal products, specifically dairy, are five times more likely to have twins. Cows, like humans, produce IGF in response to growth hormone and release it into the blood, and the IGF makes its way into their milk.

Sept 25, 06: Dwarf animals that lived on islands thousands of years ago evolved to their tiny size due to a lack of predators and competitors, not just because they were too big for their habitats, researchers said today.
. . Remains of smaller versions of bigger animals such as elephants, hippos and deer that lived on large land masses have been found on islands --a phenomenon known as 'Island Rule'. Their diminutive size has been attributed to the limited space in which they lived, but scientists at Imperial College London believe the explanation is more complex.
. . By comparing the remains of various animals they discovered that the creatures' size was due to a combination of factors including competitors and food supplies. Grass eaters like hippos were more affected by dwarfism than meat eaters. "Carnivores and herbivores don't respond to the same evolutionary pressures as far as their body sizes are concerned." Carnivores are affected by food availability and prey size, whereas herbivores are affected by the presence of other herbivores and also of predators."
. . When there is little competition for food and very few predators, herbivores tend toward miniaturization because they don't need their size to survive. Smaller animals also tend to have more offspring so their tinier size could increase the number of babies herbivores produce.
. . Miniaturization is less dramatic for carnivores and depends mainly on the size and abundance of their prey. If the prey is scarce or small, carnivores will evolve to be smaller.

Sept 24, 06: Clouds form in the forest when moist air flows in from over the Arabian Sea and pushes up against the mountains. Water droplets from the clouds collect on the trees' leaves then fall to the ground, where the water can be stored and used by the trees in drier weather. [similar to the Namib desert.]

Sept 24, 06: The earliest known bird had flight feathers on its legs that allowed it to use its hindlimbs as an extra pair of wings, a new study finds. The finding supports the theory that early birds learned to glide and parachute from trees before achieving full-fledged flight.
. . "This paper puts forward some of the strongest evidence yet that birds descended from arboreal parachuters and gliders, similar to flying squirrels."
. . Archaeopteryx was a crow-sized animal that lived about 150 million years ago and which looked like a cross between a bird and a dinosaur. It had feathers and a wishbone like birds but also reptilian features like a long bony tail, claws and teeth.
. . When the first Archaeopteryx fossil was discovered in 1861, it caused a sensation because it was the kind of transitional animal that the British naturalist Charles Darwin predicted in his theory of evolution only a few years earlier.
. . In 1877, a second Archaeopteryx specimen discovered in Germany showed a curious feature: long feathers covering its hindlimbs. For more than a century, the feathers were dismissed by most scientists as being simple, albeit unusual-looking, insulating body feathers--called "contour" feathers--that didn't play a role in the animal's flight.
. . But then, beginning in 2002, paleontologists began finding four-winged dinosaurs in China with hindlimb feathers that appeared to be important for gliding and perhaps even flying. In light of the new findings, Longrich decided it was time that Archaeopteryx was reexamined.
. . Longrich examined hindlimb feathers on five Archaeopteryx fossils using a dissecting microscope and found that the feathers had features typical of flight feathers in modern birds, including curved shafts, a self-stabilizing overlap pattern and vane asymmetry, in which the parallel row of barbs that make up the feather are longer on one side than the other.
. . Next, Longrich used standard mathematical models for flight to calculate how an extra pair of wings would have affected Archaeopteryx's flight. He found that hindlimb feathers would have allowed Archaeopteryx to fly slower and to make sharper turns.
. . "Everybody knows that birds don't have four wings, so we overlooked them even when they were right under our noses."

Sept 26, 06: In just a few generations, the male crickets on Kauai underwent a drastic genetic change that rendered them incapable of belting out courtship songs, according to a new study.
. . Typically, male field crickets sport curved wings, and by rubbing a sharp ridge of one wing with a rough part of the other, the cricket produces a mating call. But this serenade also attracts a parasitic fly. Once the insect spots a singing cricket, it deposits larvae onto the cricket. The larvae burrow into the cricket's body, where they mature and subsequently kill the cricket as they emerge from its body.
. . With each visit, the team heard fewer and fewer singing crickets. Then, in 2003 they realized the crickets were abundant but 90% of the males had flat wings.
. . The scientists figure that the quiet mutation protects the crickets from the parasitic fly. But how do they attract females? Turns out, the flat-winged male crickets have altered their behavior so they can mate successfully. The song-less males rely on the few male crickets with "normal" wings. By congregating around a serenading male, the silent crickets enable females to find and mate with them.
. . "This is seeing evolution at work."

Sept 21, 06: Swarms of tiny shrimp-like crustaceans known as krill could have a big impact on ocean life, by churning the waters and bringing nutrients from the depths up to the surface. The discovery also suggest that sea life could contribute to mixing gases in the ocean. This might influence how gases such as CO2, linked to global warming, get trapped underwater.
. . The windswept surface layers of the open seas can teem with life, but scientists could not completely explain why, since predictions suggested not enough nutrients rise up from the abyss below to account for such abundance.
. . The Canadian researchers investigated swarms of krill in Saanich Inlet, a fjord on Vancouver Island. The crustaceans migrate to the surface daily as night approaches and retreat downward as day breaks. They discovered that in the roughly 10-minute bursts in which the krill migrated, they increased turbulence by up to thousands of times.
. . The most likely animals to generate large amounts of ocean turbulence are roughly inch-sized creatures that travel together in large schools or swarms, he speculated, such as anchovies, sardines, herring or squid.

Sept 21, 06: After a long day spent socializing or learning who to flirt with, fruit flies apparently need to sleep longer, shedding light on what sleep may actually do for humans.
. . One idea scientists have about sleep is that our brains require it to process what we experienced during the day. The researchers found normal fruit flies that were allowed to socialize took hour-long daytime naps, compared to 15-minute catnaps taken by the isolated insects. Their need for sleep grew with the size of the group they socialized with.
. . Investigating memory-related genes in the flies revealed many were linked with the effect of socialization on sleep. To further experiment with how learning and development of memories affected sleep, Ganguly-Fitzgerald and her colleagues trained male fruit flies to not court females, by tricking them with unreceptive "females", who were really males generating an aphrodisiac female scent.
. . Males that learned to avoid receptive females —and thereby underwent extensive training— needed significantly more sleep than untrained males. Sleep deprivation immediately after lessons abolished both memories from their training and changes in nap length.
. . These findings suggest the brain may need sleep to bring about changes related to learning and social experiences. By further investigating which genes are linked with sleep, future research could determine what genes are linked with human sleep disorders, to help lead to "drug discovery and cures", Ganguly-Fitzgerald said.

Sept 20, 06: A 3.3 million-year-old skeleton of the earliest child ever found shows the ancient ancestor of modern humans walked upright but may also have climbed trees, scientists said, 150,000 years before Lucy.
. . They found the well-preserved remains of a three-year-old girl of the species Australopithecus afarensis --which includes the fossil skeleton known as "Lucy"-- in the Dikika area of Ethiopia. The remains provide the first evidence of what babies of early human ancestors looked like.
. . The skull, torso and upper and lower limbs, including the hand, show both human and ape-like features. The state of the ancient bones suggest she was buried in a flood which may also have caused her death.
. . The lower part of the body, which includes the foot, the shin bone and the thigh bone clearly shows that this species was an upright walking creature, but some of the features from the upper part of the body, including the shoulder blade and arms are more ape-like. The fingers are long and curved which suggest she might have been able to swing through trees.
. . An analysis of the sediment in which the remains were found enabled researchers to build a picture of the type of environment in which the child lived. It was a lush area with flowing water, forests and grassland which was also affected by volcanic eruptions.

Sept 20, 06: Seeds which have been stored away since the time of George III have been persuaded into new life. Scientists from the Millennium Seed Bank at Kew, have induced seeds from three species to germinate.
. . They had been brought to Britain from South Africa by a Dutch merchant in 1803, and were found in a notebook stored in the National Archives. Given this history, the team said it was surprised by their success. "They had been kept under pretty poor conditions."
. . The three successes are a legume, Liparia villosa, and two species not yet identified, one a protea and the other an acacia.
. . These are not the oldest seeds ever tempted into life. Four years ago scientists in the US germinated lotus seeds which had been carbon-dated as 500 years old; more recently, an Israeli team claimed to have grown a date palm from a 2,000 year old seed.

Sept 19, 06: Experts have revealed details of the "remarkable" sex life of lichens in a new travelling exhibition. The study explains how lichens either "blast" out algae and fungi to form new colonies or form surface "pegs" which are broken off and spread by animals. Scottish Natural Heritage said the fungus provides a home for the alga which in turn provides it with food. "Lichens are intriguing because each one is made up of two species."

Sept 21, 06: Scientists combing through undersea fauna off Indonesia's Papua province said they had discovered dozens of new species, including a shark that walks on its fins and a shrimp that looks like a praying mantis. Bird's Head Seascape is under danger from fishermen who use dynamite and cyanide to net their catches.

Sept 18, 06: Exotic animals roaming free are becoming an increasingly common sight in the UK and its waters, a study says. [Whatcha know; the word Exotic is used correctly here!] Climate change, zoo thefts and escapes are thought to have contributed to the rise, said the study compiled by Disney along with animal groups.
. . The survey recorded 5,931 apparent sightings of big cats, 332 of wild boars and 3,389 of sharks since 2000 --with figures expected to rise. The 10,000 sightings include a penguin, three pandas and 51 wallabies.

Sept 18, 06: Scientists said they found two types of shark, exotic "flasher" fish and corals among 52 new species in seas off Indonesia, confirming the western Pacific as the richest marine habitat on earth. "We feel very confident that this is the epicenter of marine biodiversity" in the world, said Mark Erdmann, a U.S. scientist at Conservation International who led two surveys this year.
. . They urged more protection for seas around the Bird's Head peninsula at the western end of New Guinea island from threats including mining and dynamite fishing that can smash coral reefs.
. . The scientists found 24 new species of fish, including two types of epaulette shark, slim and spotty growing up to about 1.2 meters (4 ft) long. Among other finds were 20 new species of coral and eight previously unknown types of shrimp.
. . Erdmann said the region, covering about 18,000 sq km, had a greater concentration of species than Australia's Great Barrier Reef. The area surveyed was the center of a "Coral Triangle" --between Indonesia, the Philippines, Papua New Guinea and the Solomon Islands. Around the Bird's Head peninsula, there were 1,223 species of fish and 600 types of corals.
. . The Great Barrier Reef, covering an area 10 times bigger, has slightly more types of fish --1,464 species-- but just 405 species of coral. And the bigger Caribbean Sea has fewer than 1,000 species of fish and just 58 types of coral.

Sept 15, 06: One simple answer to why some male lions do not have manes, or grow skimpy thatches of hair around their necks, is that the animals are trying to stay cool, researchers said.
. . Theories have abounded about the evolutionary purpose of the bushy manes associated with the "king of beasts". Some scientists have speculated they are designed to attract females while protecting their necks from the fangs of rivals. But researchers at Chicago's Field Museum of Natural History said maneless or thinly maned lions in Kenya's Tsavo wildlife reserve enjoy plenty of female company.
. . Comparing lions in the hot, humid Tsavo reserve to those living at the cooler, higher elevations of the Serengeti plain, they reported that Tsavo lions had smaller manes than their counterparts. Their smaller manes appeared to do nothing to diminish their mating capacity, they added, observing small-maned lions serving as dominant males in prides. "We propose that all lions develop manes in accordance with local climatic regimes."

Women speak 20k words a day. Men, 7k.

Sept 13, 06: Neandertals survived for thousands of years longer than scientists thought, with small lingering bands finding refuge in a massive cave near the southern tip of Spain, new research suggests.
. . The work contends that Neandertals were using a cave in Gibraltar at least 2,000 years later than their presence had been firmly documented anywhere before, researchers said.
. . The paper says charcoal samples from fires that Neandertals set in the cave are about 28,000 years old and maybe just 24,000 years old. Experts are divided on how strong a case the paper makes.
. . They didn't appear to encounter each other in Gibraltar at Gorham's Cave. More than 5,000 years separate the last traces of the Neandertals from the earliest evidence of modern humans, Finlayson said. He believes the area near the cave contained small bands of Neandertals and of advancing moderns at the same time, but over a large and varied landscape. So it's not clear if the two groups ever met, he said.
. . This now prolonged span of time in which modern humans and Neandertals could have interacted reopens possibilities they might have interbred, experts added.
. . The researchers investigated Gorham's Cave, where Neandertal stone tools such as spear tips were found more than 50 years ago. Neandertal tools differ from those of modern humans by the way the rock was chipped off and trimmed and by their very size and weight. "Neandertals made heavy spears for close quarter ambush hunting of large animals such as rhinos or elephants. Tools of modern people were lighter and perhaps more portable for people who were on the move."
. . While the rest of Europe was cooling, the area around Gibraltar back then "resembled a European Serengeti", Finlayson said. Leopards, hyenas, lynxes, wolves and bears lived amongst wild cattle, horses, deer, ibexes, oryxes and rhinos, all surrounded by olive trees and stone pines, with partridges and ducks overhead, tortoises in the underbrush and mussels, limpets and other shellfish in the waters.
. . This natural richness of wildlife and plants in the nearby sandy plains, woodlands, shrublands, wetlands, cliffs and coastline probably helped the Neandertals to persist, he added. Indeed, evidence at the cave shows the Neandertals likely used it as a shelter on and off "for 100,000 years."
. . As the climate cooled, the forested and semi-forested areas Neandertals were best adapted to were replaced in Europe by tundra from the north and steppe from the east. Modern humans, who were more mobile, might have been better suited for the open expanses of these terrains. "The key was physique, which for Neandertals did not change fast enough."
. . Prior findings suggested the Neandertals went extinct in Europe 35,000 years ago, while modern humans arrived in Western Europe some 32,000 years ago. The fact the span between the arrival of modern humans and the extinction of the Neandertals looked so relatively brief hinted that Neandertals got out-competed.
. . These new findings suggest Neandertals survived after modern humans moved in, and as the environment changed due to climate shifts, Neandertals faded away. "It shows conclusively that Gorham's Cave today was the last place on the planet where we know Neandertals lived."
. . They appear in the fossil record around 230,000 years ago and, at their peak, these squat, physically powerful hunters dominated a wide range, spanning Britain and Iberia in the west to Israel in the south and Uzbekistan in the east.

Sept 10, 06: Infants and apes apparently adopt the same tactics for remembering where things are, but as children develop their strategies change, a new study shows. The findings might reveal in part how the minds of our distant ancestors shifted gears to embark on the road toward humanity.
. . There are two basic strategies animals use to remember where things are. Either they remember a thing's features, such as whether it was a banana, or they remember its place in space, such as left.
. . All animals scientists have tested seem to employ both strategies. However, if experiments are rigged such that animals had to choose between the tactics, some species, such as chickens and toads, prefer a feature-based strategy. Others, such as fish and dogs, favor a place-based strategy.
. . Researcher Daniel Haun at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany and his colleagues investigated orangutans, gorillas, bonobos, chimpanzees and humans. They wanted to see whether humanity and its closest relatives all adopted the same strategies for remembering where things are. Any changes in strategy between species or within species would shed light on how they all evolved.
. . When human infants are a year old, they favor place-based strategies like all the other great ape species do. This suggests human and ape brains start out the same, at least when it comes to remembering where things are. The most recent common ancestors between humans and all the other great apes date back to about 15 million years ago, suggesting this common preference has been part of our brain structures since at least then.
. . However, three-year-old children preferred a feature-based strategy. The researchers noted this shift in strategy coincided with a period when humans are first drawn into social life and acquire skills such as spoken language.
. . In the future, Haun explained, he and his colleagues hope to discover whether developing brain areas, such as ones tied with language, are linked with changes in strategies for remembering.

Sept 10, 06: Evidence is emerging from Africa that colors were being used in a symbolic way perhaps 200,000 years ago, a UK scientist working in the region claims. Lawrence Barham has been studying tools and other artefacts left by ancient humans at a site in Zambia.
. . He says the range of mineral pigments, or ochres, found there hints at the use of paint, perhaps to mark the body. If correct, it would push back the earliest known example of abstract thinking by at least 100,000 years.
. . Being able to conceptualize --the ability to let one thing represent another-- was a giant leap in human evolution. It was the mental activity that would eventually permit the development of sophisticated language and maths.
. . Shells from Israel that were strung as beads into a necklace or bracelet are widely accepted to be the oldest unequivocal evidence for such behavior in humans
. . At Twin Rivers, Zambia, there are red, yellow, brown, pink, black and even purple ochres. If they are scraped, they will produce a powder which can be mixed with animal fat, for example, and used as a paint.

Sept 8, 06: Neandertals are often thought of as the stray branch in the human family tree, but research now suggests the modern human is likely the odd man out.
. . "What people tend to do is draw a line from our ancestors straight to ourselves, and any group that doesn't seem to fit on that line is divergent, distinct, unusual, strange", researcher Erik Trinkaus, an anthropologist at Washington University in St. Louis, said today. "But in terms of evolution of our family tree, the genus Homo, we're the outliers and the Neandertals are more toward the core."
. . Humans are not at the inevitable end of a sequence, Trinkaus said. "It just happens that we happen to be alive today and Neandertals are not. I wanted to see to what extent Neandertals are derived, that is distinct, from the ancestral form. I also wanted to see the extent to which modern humans are derived relative to the ancestral form", Trinkaus said. Trinkaus focused on skeletal features that seemed most strongly linked to genetics, as opposed to any traits that might get influenced by lifestyle, environment or wear and tear.
. . When compared with our common ancestors, Trinkaus discovered modern humans have roughly twice as many uniquely distinct traits as Neandertals. In other words, Neandertals are more like the other members of our family tree than modern humans are. "In the broader sweep of human evolution, the more unusual group is not Neandertals, whom we tend to look at as strange, weird and unusual, but it's us, modern humans", Trinkaus said.
. . Modern humans, for example, are the only members of our family tree who lack brow ridges, Trinkaus said. "We are the only ones who have seriously shortened faces. We are the only ones with very reduced internal nasal cavities. We also have a number of detailed features of the limb skeleton that are unique."

Sept 8, 06: He's no Dumbo the Flying Elephant but with his ability to "speak", perhaps as close to the Disney cartoon character as a real life elephant can get. The Everland amusement park said its 16-year-old male Asian elephant, named Kosik, can make sounds imitating up to eight Korean words, including "sit", "no", "yes", and "lie down."
. . The pachyderm produces humanlike sounds by putting his trunk in his mouth and shaking it while exhaling —-similar to how people whistle with their fingers. But the park said it's unclear if Kosik knows the meaning of the sounds he makes.
. . "It was hard to believe myself at first", Kim said. "As I watched Kosik say something after that, I realized he was mimicking my words."

Sept 7, 06: It's a meter long, pinkish in color, smells like a lily and must be saved from extinction, conservationists said today in asking the federal government to protect the Giant Palouse Earthworm under the Endangered Species Act.
. . Long thought extinct, the worm was rediscovered in the past year to occupy tiny swatches of the heavily farmed Palouse region along the Washington-Idaho border. The worm was first found in 1897, and the species has always been elusive. It can burrow down to 5 meters deep. There have been only three reported sightings since 1987.
. . The Giant Palouse Earthworm is described as the largest and longest-lived earthworm on this continent. It reportedly gives off a peculiar flowery smell when handled, and can spit at attackers!

Sept 7, 06: An Australian fish has been officially recognized as having the briefest life-span of any vertebrate in the natural world, scientists said. Researchers said the Australian coral reef pygmy goby has an adult life-span of just 3.5 weeks. The fish found on the Great Barrier Reef took ten days to reach sexual maturity, leaving them barely three weeks of life left in which to enjoy it.

Sept 7, 06: The earliest civilizations were not a product of favorable conditions but rather a last resort in the face of dramatic shifts in the weather, a climate scientist said today.
. . Flying in the face of accepted theory that settled societies emerged from the development of static farming in good climatic conditions that produced food surpluses and allowed specialization, Nick Brooks said the opposite was true. "Civilization did not arise as the result of a benign environment which allowed humanity to indulge a preference for living in complex, urban civilized societies", he told the annual meeting of the British Association for the Advancement of Science. "On the contrary, what we tend to think of today as civilization was an accidental by-product of unplanned adaptation to catastrophic climate change. Civilization was a last resort", he added.
. . As the climate became steadily drier, formerly nomadic people were forced to come together for mutual support and to eke out the dwindling natural resources.
. . But not all of the consequences of this merging movement were beneficial --social inequality arose as did organized violence, there was no increase in life expectancy and autocratic governments emerged, Brooks said. When climate conditions improved again, there was no return to the former order. "Once the cat is out of the bag, it doesn't go back. You can't uninvent technology", Brooks said.
. . And he warned against drawing comparisons with the global warming that is predicted to raise average temperatures by around three degrees this century, noting that the temperature rise was well above that which forced the societal change 5,000 years ago.

Sept 5, 06: Experts studying chimpanzees while investigating the evolution of human social behavior have uncovered their ability to safely cross roads. They said the discovery has shown chimps' ability to cope with the risk of man-made situations. The study at Bossou, Guinea observed the chimpanzees crossing two roads --one large and busy with traffic and the other smaller and used mostly by pedestrians.
. . It found the dominant adult males took up protective positions in the group when it was tasked with crossing roads. The less fearful and physically larger adult males took up forward and rear positions, with the adult females and young occupying the protected middle space.

Sept 5, 06: Eight times, humans came to try to live in Britain, and on at least seven occasions they failed --beaten back by freezing conditions.
. . Scientists think they can now write a reasonably comprehensive history of the occupation of these isles. It stretches from 700,000 years ago and the first known settlers at Pakefield in Suffolk, through to the most recent incomers just 12,000 years or so ago. The evidence comes from the Ancient Human Occupation of Britain Project.
. . The project has established that a see-sawing climate and the presence of intermittent land access between Britain and what is now continental Europe allowed only stuttering waves of immigration.
. . "Britain has suffered some of the most extreme climate changes of any area in the world during the Pleistocene", said Professor Stringer. "So places in say South Wales would have gone from something that looked like North Africa with hippos, elephants, rhinos and hyenas, to the other extreme: to an extraordinary cold environment like northern Scandinavia."
. . "Australian aboriginals have been in Australia longer, continuously than the British people have been in Britain. There were probably people in the Americas before 12,000 years ago", Professor Stringer explained.
. . She and colleagues have found thousands of items that betray a site occupied some 60,000 years ago by Neandertals. The discoveries include the remains of mammoths, rhino and other large animals; and they hint at the sophistication these people would have had to employ to bring down such prey.

Sept 4, 06: The next several decades could prove a golden age for dinosaur hunters looking to discover new species of the ancient reptiles. A new statistical analysis predicts that more than 1,300 unique dinosaur genera await discovery. In biology, a genus is an organizational group made up of one or more separate species; the plural of genus is genera. New discoveries will decline sharply in the early 22nd century, according to his new analysis.
. . Since dinosaur research began in earnest in the 19th century, 527 genera have been found; that number is increasing by about 15% each year. The researchers predict that 75% of all discoverable genera will be found within the next 100 years, and 90% within the next 140 years. Dodson predicts that 1,850 dinosaur genera will eventually be known. It does not include avian dinosaurs such as archaeopteryx.
. . Scientists predict that nearly half of all dinosaur genera that ever existed died without leaving any trace.

Sept 3, 06: Insect bite marks in ancient leaf fossils are shedding new light on how nature bounced back after an planetisimal impact killed off the dinosaurs and much of life on Earth 65 million years ago.
. . Plant and insect biodiversity is strongly linked today: Where there are many types of plants, there are many insects to eat them. But after the mass extinction, the devastated plant and insect populations might not have been so in sync, according to a new study. "The recovery from a mass extinction was more interesting and chaotic than we thought", said study leader Peter Wilf, a paleontologist at Penn State U.
. . The K-T extinction initially marked the end of the biologically rich Cretaceous period and the beginning of the more anemic Paleocene epoch. Most Paleocene fossil sites show both low numbers of plants and insects.
. . But scientists have discovered two sites in the western US that show remarkable biodiversity -—one in plants, and one in insects. Paleontologists looked at leaf fossils for signs of the bite marks left by different species of insects. At one site, near Denver, the fossils showed that "the plant diversity was really high—like a modern rainforest", Wilf said. "It was a big shock." Wilf and his colleagues suspect that the plants were able to flourish because the ancient climate at the site was warm and wet. But the leaves unexpectedly showed few signs of insect predators. Wilf thinks the leaves were too hardy for insects to gnaw on.
. . But what really surprised paleontologists were the fossils at another site in Mexican Hat, Montana that showed just the opposite relationship. The leaf fossils found there were more typical of those discovered at other Paleocene sites. But the insect bites left on them indicated a teeming insect population. Wilf and his team haven't found any other sites that show evidence of such a robust insect population. "We don't know where [the insects] went or where they came from", he said.
. . Wilf believes these unusual fossil records show biodiversity recovery is more interesting than previously thought.

Aug 30, 06: Father Stephan Horn, a German theologian organizing the pope's meeting with 39 former students, said a fundamentalist Protestant view that God created the world in six days as described in the Book of Genesis. "Catholic theology does not endorse creationist views."
. . Catholic teaching accepts evolution as a scientific theory and does not read the Biblical story of creation literally. But it disagrees with what it calls "evolutionism", the view that the story of life has no role for God as its prime author. "The possibility that the Creator used evolution as a tool is completely acceptable for the Catholic faith", Vienna Cardinal Christoph Schoenborn, one of the two main speakers at the meeting, said last week.

Aug 30, 06: Paleontologists have uncovered a 25-million-year-old whale fossil with a monstrous set of teeth and enormous eyes on the coast of Australia. The discovery has researchers rethinking whales’ evolutionary history.
. . Scientists were surprised to find that the vicious-looking specimen is an ancestor of modern baleen whales, gentle giants of today’s seas. The fossil suggests a creature that grew to a little more than 3.5 meters, with teeth about 4cm long.
. . Baleen whales, which include the blue and humpback, feed by filtering plankton and small fish from seawater through hair-like fibers in their jaws. Their ferocious forebears, on the other hand, appear to have used their teeth to rip and chew meat, said the lead researcher.
. . Today, there are two groups of whales: Mysticetes, or baleen whales, and odontocetes, or toothed whales such as orcas and dolphins. Some modern baleens do have teeth, but they use them for filtering rather than biting. Scientists believe the two groups diverged about 35 million years ago.
. . In many ways, it is markedly different from its modern counterparts, though. The fossil whale has a more varied set of teeth and extremely long incisors, as you might expect to see on a cat or other terrestrial carnivorous animal.
. . The animal's huge eyes, which scientists associate with sharp underwater vision, are also adaptive for hunting. The whales probably couldn’t produce ultrasonic signals for echolocation or sonar though, as some modern whales can to locate prey.
. . It now appears whale evolution was more complex than a simple split 35 million years ago. Not only does the fossil add a branch to the family tree, it also fills a time gap for researchers.

Aug 24, 06: When the going gets tough, most animals instinctively cling to family. Now, scientists find that even single-celled amoebas, the simplest creatures known, favor their own in times of need.
. . Typically found in freshwater, amoebas will also sacrifice themselves for the good of the family, researchers report. "By recognizing kin, a social microbe can direct altruistic behavior towards its relatives", said Natasha Mehdiabadi, lead author of the study.

Aug 23, 06: Cows have regional accents like humans, language specialists have suggested. They decided to examine the issue after dairy farmers noticed their cows had slightly different moos, depending on which herd they came from. John Wells, Professor of Phonetics at the University of London, said regional twangs had been seen before in birds.
. . The farmers in Somerset who noticed the phenomenon said it may have been the result of the close bond between them and their animals. Farmer Lloyd Green, from Glastonbury, said: "I spend a lot of time with my ones and they definitely moo with a Somerset drawl.

Aug 23, 06: Scientists may have to rethink accepted theories of how the prehistoric earth's atmosphere developed after new discoveries in ancient sulphur raised serious questions, researchers said.
. . Up to now, it has been generally accepted that the earth's atmosphere was devoid of oxygen for some 80% of its existence.
. . Currently, scientists widely believe photosynthetic microbes helped oxygenate the planet roughly 2.4 billion years ago, and that oxygen was scant in the atmosphere before then. They base this idea on isotopes of sulfur in ancient rocks. Isotopes of sulfur all behave virtually the same chemically but have slightly different masses.
. . Rocks older than 2.4 billion years contain abnormal ratios of sulfur isotopes compared with younger rocks. The only way known to generate these abnormal ratios are reactions between sunlight and sulfurous volcanic gas in the absence of an ozone shield that would normally help screen out ultraviolet rays.
. . This implies that an oxygen-rich atmosphere, generated by oxygen-producing organisms, might be found in young planets of other stars.
. . Isotopes from two sulphur samples the team analyzed --one 2.76 billion years old from a lake bed and the other 2.92 billion years old from the sea bed-- did not indicate an oxygen-starved atmosphere.
. . The team concluded that there were two possible explanations --either that prehistoric atmospheric oxygen levels fluctuated wildly over the millennia, or that sulphur showing no oxygen might have been produced in an oxygenated atmosphere as long ago as 3.8 billion years by violent volcanic activity.

Why have humans developed music?
. . Levitin, a rock producer who went to a career in neuroscience: There are a number of different theories. One theory is that music is an evolutionary accident, piggybacking on language: We exploited language to create music just for our own pleasure. A competing view, one that Darwin held, is that music was selected by evolution because it signals certain kinds of intellectual, physical and sexual fitness to a potential mate.
. . (musical talent) signals that if you can waste your time on something that has no immediate impact on food-gathering and shelter, you’ve got your food-gathering and shelter taken care of. [That's Socio-biology!]
. . Music activates the same parts of the brain and causes the same neurochemical cocktail as a lot of other pleasurable activities like orgasms or eating chocolate -- or if you're a gambler winning a bet or using drugs if you're a drug user. Serotonin and dopamine are both involved.
. . Most people in Western society use music to regulate moods, whether it's playing something peppy in the morning or something soothing at the end of a hard day, or something that will motivate them to exercise. Joni Mitchell told me that someone once said before there was Prozac, there was her.

Aug 23, 06: When John Hutchinson, now at the Royal Veterinary College at the University of London, was in graduate school, it was still an open question whether an elephant moving at high speeds could be considered running. His new study finds that although they're no greyhounds or cheetahs, fast-moving elephants have a springy step that qualifies them as runners within the animal world.
. . Six special cameras took 240 pictures per second and could capture far more detail than the naked eye or conventional video could. They soon found that although elephants don't lift all four feet at once, a previous definition of running, they showed signs of using their legs like pogo sticks, compressing and rebounding with each step.
. . Many animals are now known to bounce without leaving the ground—many birds, insects, and Icelandic ponies for example. Even at their top speed of 15 mph, elephants keep one or two feet on the ground at all times.
. . In robotics, the elephant locomotion could be used as a model for building giant legged vehicles that move as economically as these large animals.

Aug 23, 06: A new study finds there are more venomous fish than venomous snakes. The 1,200 presumably venomous fish tallied in a new study is six times previous estimates. Fish with a biting bite outnumber all other venomous vertebrates combined, in fact.
. . More than 50,000 people are poisoned by fish bites every year, Smith and his colleague said. Symptoms range from blisters to death. Among the fish to look out for: lionfishes, catfishes, scorpionfishes, weeverfishes, toadfishes, surgeonfishes, scats, jacks, rabbitfishes, stargazers, and stonefishes.
. . The study could be important for the development of new drugs. Venoms pack proteins that can be used to develop drugs to treat a range of ails from allergies to pain and even cancer, the scientists say. While many creatures have been tapped for drug development, fish remain a relatively untapped resource.
. . Six treatments for stroke or cancer developed from snake venom are nearing FDA review, the scientists point out. Scorpion venom has been used in a brain cancer treatment.

Aug 21, 06: Scientists have discovered the fastest bite in the world, one so explosive it can be used to send the Latin American ant that performs it flying through the air to escape predators.
. . Since the 1800s, researchers had seen trap-jaw ants zing through the air based on the power of their incredibly strong jaws. Until now, no one was able to prove the ants intentionally used their jaws for jumping.
. . They found the ant's jaws accelerate at 100,000 times the force of gravity. This means they can snap shut 2,300 times faster than a blink of the eye to reach speeds up to 235 kph (145 mph), exerting forces 300 to 500 times the ant's body weight. They had to use high-speed video cameras capable of taking up to 250,000 frames per second to film the ant jaws, roughly 10,000 faster than speeds movies are usually shot at.
. . Falcons can dive as fast as 300 mph, but they rely on gravity and start from great heights. Aside from getting a gravity assist or other help, these snapping ant jaws are by far the fastest-moving body parts in the animal kingdom.

Aug 18, 06: As we yawn and open our eyes in the morning, the brain stem sends little puffs of nitric oxide to another part of the brain, the thalamus, which then directs it elsewhere. Like a computer booting up its operating system before running more complicated programs, the nitric oxide triggers certain functions that set the stage for more complex brain operations, according to a new study.
. . In these first moments of the day, sensory information floods the system—the bright sunlight coming through the curtains, the time on the screeching alarm clock—and all of it needs to be processed and organized, so the brain can understand its surroundings and begin to perform more complex tasks.
. . "The thinking part of the brain is applying a sort of stencil to the information coming in and what the nitric oxide is doing is allowing more refinement of that stencil", says Dwayne Godwin, an associate professor at Wake Forest University and lead author of the study, which was funded by the National Eye Institute.
. . The little two-atom molecule, it seems, is partly responsible for our ability to perceive whatever it is we're sensing.
. . The finding changes the way scientists understand nitric oxide's role in the brain, and it also has them rethinking the function of the thalamus, where it is released. While this study is the first to identify nitric oxide's role in the thalamus, elsewhere in the body it was already known to have an important, if somewhat different function. The molecule is actually integral to controlling blood flow and is, in fact, the molecule Viagra targets in order to increase blood flow to the penis.
. . The teeny molecule might have other medical uses. "This study shows a unique role for nitric oxide. It may help us to someday understand what goes wrong in diseases that affect cognitive processing, such as attention deficit disorder or schizophrenia, and it adds to our fundamental understanding of how we perceive the world around us", Godwin said.

Aug 16, 06: Scientists believe they have found a key gene that helped the human brain evolve from our chimp-like ancestors. In just a few million years, one area of the human genome seems to have evolved about 70 times faster than the rest of our genetic code. It appears to have a role in a rapid tripling of the size of the brain's crucial cerebral cortex.
. . The team found strong but still circumstantial evidence that a certain gene, called HAR1F, may provide an important answer to the question: "What makes humans brainier than other primates?" Human brains are triple the size of chimp brains.
. . Looking at 49 areas that have changed the most between the human and chimpanzee genomes, Haussler zeroed in on an area with "a very dramatic change in a relatively short period of time."
. . That one gene didn't exist until 300 million years ago and is present only in mammals and birds, not fish or animals without backbones. But then it didn't change much at all. There are only two differences in that one gene between a chimp and a chicken, Haussler said. But there are 18 differences in that one gene between human and chimp and they all seemed to occur in the development of man, he said.
. . However, the gene changed so fast that Clark said that he has a hard time believing it unless something unusual happened in a mutation. It's not part of normal evolution, he said. Haussler attributed the dramatic change to the stress of man getting out of trees and walking on two feet. And it's not just that this gene changed a lot. There is also its involvement with the cerebral cortex, which is responsible for some of the more complex brain functions, including language and information processing.
. . The scientists still don't know specifically what the gene does. But they know that this same gene turns on in human fetuses at seven weeks after conception and then shuts down at 19 weeks.

Aug 16, 06: They could be the missing links of human genetic evolution -- areas of human DNA that changed dramatically after the evolutionary division from chimpanzees, though they had remained almost unchanged for millennia before.
. . Scientists from the United States, Belgium and France identified 49 "human accelerated regions" (HARs) showing a lot of genetic activity. In the most active, identified as HAR1, they found 18 out of the 118 nucleotides had changed since evolutionary separation from chimps some 6 million years ago, while only two had changed in the 310 million years separating the evolutionary lines of chimps and chickens.
. . "Right now we have very suggestive evidence that it might be involved at a critical step in brain development, but we still need to prove that it really makes a difference. It is extremely unlikely that the evolution of just one region in the genome made the difference between our brains and the brains of non-human primates", he said. It is much more likely to be a series of many, many small changes, each very important, but none doing the entire job by itself."

Aug 16, 06: A ferocious-looking fossil with sharp teeth found in Australia shows that ancestors of today's toothless blue whales were not all "gentle giants", a report said.
. . The 25 million-year-old fossil is of an early type of baleen whale, a group including modern humpback whales, minke whales and blue whales that feed via baleen, comb-like plates in their mouths that filter plankton from sea water. "This bizarre, new baleen whale did not even have baleen." It was probably up to 3.5 meters long.
. . Most scientists have believed that baleen whales quickly evolved baleen for feeding on tiny fish and plankton after breaking from a common ancestor with toothed whales almost 40 million years ago. Whales evolved from land mammals, where their closest relative is the hippopotamus. Modern toothed whales include dolphins, killer whales and sperm whales.
. . The fossil was found near Jan Juc, a town in Victoria, south-eastern Australia, and dubbed "Janjucetus." Its sharp teeth were about 3 cms long and it also had large eyes, apparently suited for hunting.

Aug 15, 06: Australian scientists have called on the country's farmers to report any ugly sheep found in their flocks. A campaign called "Xtreme sheep" aims to study sheep with undesirable wool features to unlock the genetic makeup of the prized merino and ensure production of its high quality fleece.
. . Ugly lambs --with uneven wool, strange fibers, clumps of wool that fall out, bare patches, no wool, or highly wrinkled skin-- are usually culled by farmers. "Before sending them to the abattoir, we'd like farmers to talk to us first, because studying animals with extreme features offers one of the most efficient ways to find good genes that can impact on certain wool traits."
. . The institute hopes to the DNA study will lead to improvements in Australia's merino wool, making it stretchier, less scratchy, shinier and easier to spin, and better able to compete against synthetic fibers.
. . So far, only 10 ugly sheep have been found this lambing season, which stretches from April to September, when statistically there could be hundreds.

Aug 15, 06: Giant prehistoric kangaroos and wombat-like creatures the size of hippopotamuses were not killed off by human hunters but by climate change and starvation, an Australian study has found.
. . The study, based on the re-excavation of a site at Lake Menindee in western New South Wales state, found strong evidence that the cold climates of the last Ice Age were followed by a drought which caused the mammals to starve to death.
. . The site was first studied in the 1950s, when scientists argued that hunting implements found there meant that humans had killed off the giant beasts. "Because scientists at the time couldn't date the items, they assumed they were the same age and extrapolated from that that the humans killed off the giant marsupials."
. . Cupper's team used state-of-the-art radio-carbon and luminescence dating techniques unavailable to earlier scientists to conclude that humans came to the area much later. Items could be dated back as far as 60,000 years ago. "People were not even at the scene of the crime, with the oldest evidence of humans at the site at least 10,000 years after the giant mammals went extinct" archaeologist Jacqui Duncan said. "The animals probably died of starvation during drought around 55,000 years ago", she said.
. . The largest marsupials to roam the Australian outback weighed up to 2.5 metric tons.

Aug 14, 06: Before she made the discovery, Price, who spent more than 20 years studying desert rodent communities, couldn't understand how several rodent species co-existed in an area with scant resources and yet none out-competed the others. It turns out some weren't playing fair.
. . Pocket mice steal from their bigger, faster cousins, the kangaroo rats, which are very good at bounding around on their hind legs and gathering seeds. After the plants have dropped all their seeds and the frenzied scramble for them is over, the kangaroo rats store what they've collected in caches, from which they feed the rest of the year.
. . The tiny pocket mice are expert at finding and making off with stored seeds. This kind of parasitic relationship has been observed in just a few other animal communities.
. . She also sees a broader application of the finding. "We can't conserve biodiversity if we don't understand the processes that maintain it", she said.

Aug 11, 06: Some 15 years ago, blue mussels knew their enemies and had a rather peaceful life in the New England waters. But when an invasive crab species turned up, the mussels moved quickly to defend themselves against this new predator by thickening their shells.
. . Such rapid evolutionary response is a "nanosecond" compared with the thousands of years that it normally takes for a species to respond to a predator. Crabs prey on blue mussels by crushing their shells. The mussels most likely evolved quickly because they are used to being prey to many species in these waters.

Aug 10, 06: Scientists at Emory University have developed a new type of map of the human genome that could one day lead to breakthroughs in personalized medicine. As much as 99% of human code is identical-- it's the last 1% that determines individual traits like difference in appearance, life expectancy, resistance to drugs and susceptibility to disease.
. . A team of scientists in Emory's School of Medicine said that they've advanced the study of the last 1% of genetic variation by producing a map of more than 400,000 insertions and deletions (INDELs) in the human genome. In simpler terms, they've shown 400,000 different naturally occurring variations in genetic code, or so-called polymorphisms, which can help explain idiosyncrasies in humans.
. . There are variations called single nucleotide polymorphisms (SNPs), of which there are more than 2 million in the human population. SNPs are like changing one letter in those building blocks. So an SNP might be A, A, C, G.
. . In contrast, INDELs either insert or delete hundreds of letters, or chemical building blocks. When those changes happen, a human's genetic makeup is altered. "If the genome is an instruction book, SNPs are places where the instruction book varies by one letter, like a misspelling."
. . He believes the map of INDELs will grow to 2 million naturally occurring variations. In contrast, the map of SNPs will likely grow to 10 million. Of course, scientifically, the variations are not correlated to specific traits yet, but that's what scientists like Devine hope the research will lead to.

Aug 10, 06: A comparison of peoples' views in 34 countries finds that the United States ranks near the bottom when it comes to public acceptance of evolution. Only Turkey ranked lower.
. . Among the factors contributing to America's low score are poor understanding of biology, especially genetics, the politicization of science and the literal interpretation of the Bible by a small but vocal group of American Christians, the researchers say. “American Protestantism is more fundamentalist than anybody except perhaps the Islamic fundamentalist, which is why Turkey and we are so close."
. . The study found that over the past 20 years:
. . * The percentage of U.S. adults who accept evolution declined from 45 to 40%.
. . * The percentage overtly rejecting evolution declined from 48 to 39%, however.
. . * And the percentage of adults who were unsure increased, from 7 to 21%.

Of the other countries surveyed, only Turkey ranked lower, with about 25% of the population accepting evolution and 75% rejecting it. In Iceland, Denmark, Sweden and France, 80% or more of adults accepted evolution; in Japan, 78% of adults did.
. . The researchers also compared 10 independent variables—including religious belief, political ideology and understanding of concepts from genetics, or “genetic literacy”—between adults in America and nine European countries to determine whether these factors could predict attitudes toward evolution.
. . Mainstream Protestants in both the United States and Europe instead treat Genesis as metaphorical, the researchers say. 'Whether it’s the Bible or the Koran, there are some people who think it’s everything you need to know", Miller said. “Other people say these are very interesting metaphorical stories in that they give us guidance, but they’re not science books.” This latter view is also shared by the Catholic Church.
. . Miller says that it makes about as much sense for politicians to oppose evolution in their campaigns as it is for them to advocate that the Earth is flat and promise to pass legislation saying so if elected to office.

Aug 10, 06: Without a trip to an eye doctor, some snakes have developed their own vision-correcting devices. Scientists have discovered how pit vipers can turn blurry blobs into useful images with striking clarity. Turns out it's all in their tiny minds.
. . Two groups of snakes, pit vipers and boids (a family that includes boa constrictors) sport a pit organ on either side of their heads. Stretched across each pencil-eraser-size cavity is a membrane that can detect infrared light—which is heat—emitted by nearby prey. Scientists have known that pit vipers utilize these organs similar to the way a pinhole camera works.
. . The "pithole" acts like a lens, forcing light from the source to form a tiny point on the membrane —the "camera's film". By focusing the light to such a tiny point, pinhole cameras can produce crisp images. But an aperture so tiny would never let in enough infrared waves, which have a much lower frequency than visible light, to stimulate the membrane. The pit openings of the snake are too large, therefore, to produce crisp images.
. . Using a computer model, van Hemmen's team found that some snakes rely on a network of neurons in their brains to bring a blurry image into view. The brain network serves effectively as corrective lenses. The model showed that an infrared signal from each of the membrane's heat receptors triggers a neuron to fire. This firing rate varies with respect to input from the other receptors. By fine-tuning how the approximately 2,000 heat receptors interact, van Hemmen's team created strike-worthy images.
. . None of this is overly complex, either. Snakes have small brains, so the researchers kept their computer model simple, concluding that "even a crude network dramatically improves infrared imaging."

Aug 9, 06: Baby bats babble just like newborn human babes, a new study finds.
. . Babbling is thought to be a kind of vocal play that provides human infants a chance to train their vocal tract muscles in preparation for speech and to practice combining the syllables they will use as adults. Humans begin babbling at about 7 months of age.
. . Apart from a few other primates, like the pygmy marmoset, babbling has never been observed in any other mammals until now. However, certain species of songbirds are known to engage in a similar behavior, called "subsong." [But I contend that bats should be included as primates!]

Through monitoring the brains of infants, researchers confirmed that infants as early as six months in age can detect mathematical errors, putting to rest a debate that has been ongoing for over a decade.
. . A team of scientists from the US and Israel exposed 24 infants to a videotaped puppet show. They used the puppets for addition and subtraction while observing the reaction of the babies. For example, they started the show with two dolls. Before the show ended, a doll was removed and then the infant's vision was blocked with a screen. When the screen was taken away, either one doll was left, as expected, or two dolls, which would not be mathematically correct. The infants looked at the screen longer when the number of dolls was two, which did not agree with the solution of 2 – 1 = 1.
. . One study showed that babies have the ability to recognize and match numbers. When they heard two voices, the gazed at an image with two faces. And when they heard three voices, they looked at an image with three faces. Another study illustrated that five-year-olds can perform relatively complex math operations such as figuring out if the sum of two numbers is greater than or less than a third number.

Aug 9, 06: Paleontologists have created detailed three-dimensional images of evolution's first multicellular creatures in their embryonic stages, some so detailed that they reveal more about the development of long-extinct creatures than scientists know about their modern counterparts!
. . They scanned tiny balls of fossilized cells with powerful X-rays and then used a computer to assemble the views into microscopic CT scans. Some of the embryos exhibit hitherto unknown mechanisms of embryonic development that have since gone extinct. Others have combinations of traits that put them near the lowest branches of the animal kingdom's evolutionary tree.
. . Using the new technique, he and his colleagues have been able to create virtual cutaways, cross-sections and, by stringing together images of embryos at different stages of development, virtual time-lapse sequences of the animals' metamorphosis.
. . The creature sits very near a three-way split on the evolutionary tree that separated the unsegmented nematode worms and their segmented cousins from the gigantic arthropod phylum, which includes crustaceans, insects and spiders.
. . Another image shows that a segmented creature known as Pseudooides had a very unusual means of assembling itself. Modern segmented animals either develop all of their segments early and then simply get bigger, or they grow by adding segments to their hind ends. But Pseudooides added its segments in the middle, "which is really totally bizarre."
. . Interestingly, paleontologists have yet to find any definitive examples of larval stages among their microfossils. That suggests either that larvae are especially difficult to fossilize or that development through juvenile stages developed later in evolutionary history.
. . Aug 9, 06: A new technique allowing virtual dissections of half-billion year old fossil embryos is producing the first three-dimensional images of the dawn of life. It reveals a universe of detail impossible using previous methods, and researchers at Bristol University in southwestern England said it was pushing back the frontiers of science much as the scanning electron microscope did half a century ago.
. . These fossils are the most precious of all because they contain information about the evolutionary changes that have occurred in embryos over the past 500 million years", he added.
. . In contrast to existing methods of exterior observation or destructive sectioning of fossil embryos, synchroton-radiation X-ray tomographic microscopy (SRXTM) leaves the tiny fossils untouched but gives graphic details of their structure. "We can see details less than 1,000th of a millimeter in dimension." "We can look at any and every part of the fossil --inside and out-- without harming it and then virtually dissect it however we like."

Aug 7, 06: It's not Jurassic Park, but scientists have reconstructed a 530-million-year-old gene by piecing together key portions of two modern genes descended from it. "We've shown some of the elements involved in the process of evolution by reversing this process and reconstructing a gene that later became two genes", said study team member Mario Capecchi of the University of Utah School of Medicine.
. . The achievement could lead to new types of gene therapy, in which a damaged gene could be restored by pairing parts of it with portions from a similar gene from another part of the body.
. . Early animals had 13 Hox genes until about 500 million years ago. Those 13 Hox genes multiplied four times, but some were lost because they were redundant. Today, humans and other mammals today have 39 Hox genes. The reconstructed gene lacks Hoxc1 and Hoxd1, two descendent genes that vanished during evolution because they were either redundant or played minor roles.
. . The study could lead to new approaches to gene therapy, the researchers say. "It shows that genes are not as different as we thought, and that we can perhaps tweak and recruit one to do the job of another that is mutated and not as easy to fix."

Australia's island state of Tasmania risks losing its status as a "Noah's Ark" for rare species with the discovery that foxes have probably begun breeding there. Somebody had brought them for hunting "sport".

Late-night comedians have been making cracks about Kansas, portraying it as backward and ignorant. Last November, the Board of Education's 6-to-4 conservative Republican majority rewrote testing standards for public schools to incorporate language supported by advocates of intelligent design, which holds that life is so complex it must have been created by some kind of higher power. [Like a "higher power" wouldn't be smart enough to design a self-adapting ecology!!]

Aug 2, 06: Conservative Republicans who pushed anti-evolution standards back into Kansas schools last year have lost control of the state Board of Education once again. As a result of the vote, board members and candidates who know evolution is well-supported by evidence will have a 6-4 majority.
. . The most closely watched race was in western Kansas, where incumbent conservative Connie Morris lost her GOP primary. The former teacher had described evolution as "an age-old fairy tale" and "a nice bedtime story" unsupported by science.
. . Pro-evolution Republican Jana Shaver picked off a conservative incumbent and won the primary for the open seat. Janet Waugh, a Kansas City Democrat who opposed the new standards, easily defeated a more conservative Democrat who favored the anti-evolution language.

Transsexual hen's crow wreaks havoc in the henhouse. A hen in southern Sweden that has grown a rooster comb, tail and wattle and begun to crow is wreaking havoc in its henhouse, where the rooster is hopping mad.

Aug 4, 06: A parasitic microbe commonly found in cats might have helped shape entire human cultures by manipulating the personalities of infected individuals, according to a new study.
. . Infection by a Toxoplasma gondii could make some individuals more prone to some forms of neuroticism and could lead to differences among cultures if enough people are infected.
. . Lafferty found that people living in those with higher rates of T. gondii infection scored higher on average for neuroticism, defined as an emotional or mental disorder characterized by high levels of anxiety, insecurity or depression.
. . T. gondii infects both wild and domestic cats, but it is carried by many warm-blooded mammals. One recent study showed that the parasite makes normally cautious rats outgoing and more prone to engage in reckless behavior, such as hanging around areas frequently marked by cat urine, making the rats easy targets.
. . Scientists estimate that the parasite has infected about 3 billion people, or about half of the human population. Studies by researchers in the Czech Republic have suggested T. gondii might have subtle but long-term effects on its human hosts. The parasite is thought to have different, and often opposite effects in men versus women, but both genders appear to develop a form of neuroticism called "guilt proneness."
. . Other studies have also found links between the parasite and schizophrenia. T. gondii infection is known to damage astrocytes, support cells in the brain that are also affected during schizophrenia. Pregnant women with high levels of antibodies to the parasite are also more likely to give birth to children who will develop the disorder.
. . The distribution of T. gondii could explain differences in cultural aspects that relate to ego, money, material possessions, work and rules, Lafferty added. In some countries, infections by the cat parasite are very rare, while in others nearly all adults are infected.
. . To test his hypothesis, Lafferty looked at published data on cultural dimensions and average personalities for different countries. The countries examined also kept records of the prevalence of T. gondii antibodies in women of childbearing age. Countries with high prevalence of T. gondii infection also had higher average neuroticism scores.
. . The parasite's eggs can survive longer in humid, low-altitude regions, especially at mid latitudes that have infrequent freezing and thawing.

Aug 4, 06: Chimps and large predatory cats are more likely to target dimwitted prey less capable of escaping attack, a new study reports.
. . The researchers focused on predators from Africa and South America such as chimpanzees, jaguars, leopards and pumas. The scientists compared how often a prey species appeared in the wild with how often it turned up in the diets of the predators.
. . The results suggest prey with small brains relative to their body size, such as mongooses, the red river hog and certain small antelope, were hunted more often than prey with larger brains. Among all the prey species considered, primates, which have large brains compared to most other mammals, were targeted the least.
. . The finding supports a hypothesis first proposed in the early 1990s that predator avoidance has been a major driving force in the evolution of brain size. Altering behavior is easier than evolving armor or a faster gait, but this requires greater cognitive capacities. This in turn requires a bigger brain.
. . A separate study earlier this year found that one type of monkey even has warning calls that distinguish between the threat of a preying bird or a ground predator. The black-capped chickadee, certainly no birdbrain, can not only warn of a threat but tell other birds how big the predator is.

Aug 2, 06: Bumblebees like it hot and learn to use the color of plants to select blooms with the warmest nectar, scientists said today. Through trial and error, bumblebees learn which flowers are the hot spots which offer an additional reward in the form of heat or energy.
. . When researchers at Queen Mary, University of London used four different colored artificial flowers with varying temperatures, the majority of the bees selected the darker colored, warmer flowers. Even when the colors and temperatures were switched, the bees still preferred the warmer blooms. "The interesting thing is that bees don't just prefer the warmer drinks - they learn to predict the flower temperature from the flower color."
. . Because bees have to invest energy to maintain body temperature, the warmth of a flower, identified by color, is another incentive.

July 31, 06: A new study shows ants are more aggressive when they think they’re part of a larger group.
. . The research showed that ants fighting for a piece of tuna soaked in pineapple juice --a precious commodity for the invertebrates-- acted more aggressively if they felt they were part of a community. To foster feelings of kinship, researcher Colby Tanner, a graduate student at the University of Utah, kept one set of F. xerophila ants in a densely populated environment, where they were constantly bumping into each other. He put a second group of F. xerophila ants in a more sparsely populated area, where they had little contact with others.
. . In fighting trials against their natural enemy, a different species of ant, the groups acted very differently. While all the fights were evenly matched --either five-on-five or one-on-one—ants from the sparsely populated setting were more hesitant to scrap. Ants raised in a highly populated environment were more aggressive.

July 31, 06: The oceans are teeming with 10 to 100 more types of bacteria than previously believed, many of them unknown, according to a study released today that has jolted scientists' understanding of evolution in the seas.
. . Microbes were fished up from eight sites in the Atlantic and Pacific Oceans at depths of 550 to 4,100 meters. The locations included extreme environments, both hot and cold, such as the North Atlantic and a hydrothermal vent located on an underwater Pacific volcano off the coast of Oregon.
. . Using a new genetic mapping technique, U.S., Dutch and Spanish scientists said they found more than 20,000 different types of microbe in a single liter of water from deep sites in the Pacific and Atlantic Oceans. "These observations blow away all previous estimates of bacterial diversity in the ocean. Microbiologists have formally described 5,000 microbial species. This study shows we have barely scratched the surface."
. . Past studies had suggested that one liter of water would contain 1,000 to 3,000 types of microbe --the oldest form of life on the planet. Microbes make up more than 90% of the total mass of life in the seas, from bacteria to whales. "We've found 10 or maybe 100 times more diversity..."
. . Sogin said the findings suggested there might be more than 10 million types of bacteria in the seas alone. Until recent years, estimates of the total number of species on earth --from microbes to elephants-- were below a million.
. . "The number of different kinds of bacteria in the oceans could eclipse five to 10 million." The researchers think that they might serve as a gene pool to preserve genetic innovations. If environmental changes wiped out a dominant species, the low-abundance ones with a more suitable genetic makeup would be ready to take over.
. . The census keeps a record of the distribution and numbers of the microbes. Scientists can then trace how the organisms adapt to changes and also, in the long run, understand what evolutionary driving forces might be at play.
. . One possibility was that some types of microbe were rare in some parts of the oceans but common in others --challenging traditional views of the seas as a homogenous bacterial soup. "There might be a 'bio-geography' of micro-organisms in the sea, something that microbiologists have been debating for perhaps hundreds of years."
. . Sogin said the variety of life might also benefit pharmaceutical and biotechnology firms.

July 31, 06: Having an extra ounce of fat is unforgivable for many gym goers, but for ants, it's a matter of livelihood and they do all they can to store some of this energy source. And they share.
. . When times are good and food is plenty, ants invest heavily in storing fat so that they can use it when famine strikes, a new study finds. They can pass the fat through oral secretions to other members of their colony or through unfertilized eggs when needed.
. . "Understanding the regulation of nutrient reserves, particularly fat storage, at the individual and colony levels is critical to understanding both the division of labor characteristics of social insect colonies and the evolution of important colony life-history traits such as the timing of reproduction, founding mode, and over-wintering behavior", said Daniel Hahn of the University of Florida.

July 29, 06: Humans aren't the only creatures that vocalize during sex. While mating, female Physocylus globosus spiders emit high-frequency squeaks to let males know what they should be doing, a new study finds. Called stridulations, the shrill cries sound like squeaky leather.
. . Female spiders are able to store sperm from different males inside their bodies and can choose which lucky male spider gets to fertilize her eggs. Squeezing stimulates the females and raises a male's chances that his sperm will be selected. "Males that squeezed females more often during copulation sired more offspring than males that squeezed less often." However, if done too forcefully, the action can physically damage the female. If a male squeezes too hard or too long, the female squeaks to let him know to pick up the pace but to take it easy.
. . To produce the squeaking sounds, females scrape a part of their "pedipalp" -—a leg-like appendage located near their mouths—- against the file-like surface of their fangs, or "chelicera."
. . A male spider's genitalia are located at the end of its pedipalp. During sex, he inserts this tip into the female. Muscles near the base of the pedipalp flex during sex, creating the rhythmic squeezing motions that cause a female to cry out.
. . They found that the number of squeezes the males made were associated with the number of times the females cried out during sex. Stridulations became more frequent if males failed to loosen a squeeze in response to a previous plea.
. . Obedient males that consistently followed the female's directions ended up siring more offspring. It's thought that the squeezing motion propels the male's sperm deeper into the female's body, where it is more likely to fertilize her eggs.

July 28, 06: Using a retina plucked from the eye of guinea pigs as a model, scientists estimate that our eyes transmit visual information to our brains at about the same rate as an Ethernet connection.

July 28, 06: A man's taste in women depends on how hungry he is, according to research. A man on an empty stomach is more likely to be attracted to a heavier woman. The connection is believed to stem from an evolutionary trait that links body size with health.

July 27, 06: UK scientists say they have solved the mystery of why prehistoric flying reptiles grew crests on their heads.
. . A rare juvenile skull specimen found in Brazil shows the crest appeared at puberty, suggesting it was used to attract attention from the opposite sex --like a peacock's tail to attract a mate.
. . Rather than forming one large triangular crest of bone extending from the snout to the back of the head, it was made up of two pieces. One crest came from the back of the skull and the other from the front of the snout. The crest that sprouted from the front grew backwards, only fusing to form one large crest when the pterosaur reached puberty.

July 25, 06: If you were a male praying mantid, the top item on your prayer list would be to survive sex. Female praying mantids are notorious for eating males after they mate.
. . Now for the first time, scientists have experimentally shown that the males are hip to the risk and not too keen on being food.
. . The researchers toyed with the physical position of females and how hungry they were, then noted how males responded. "We know that hungry females are more likely to cannibalize and a head-on orientation makes it easier for her to attack the male with her predatory front legs."
. . The guys responded to greater risk by slowing their approach, increasing courtship behavior, and mounting from a greater—and possibly safer—distance, the scientists say. "This shows that male mantids actively assess variation in risk and change their behavior to reduce the chance of being cannibalized."
. . (You may have heard these insects called "praying mantis", but mantis refers to the genus Mantis. "Only some praying mantids belong to the genus Mantis.")

July 26, 06: The triangular shark fin that sends frightened swimmers scrambling to shore is made using the same genes that help form the arms and legs of humans, a new study reports. The genes come from an ancient ancestor shared by sharks and humans. They also found that the genes are vital for the formation of the ribbon-like fins on the back of lampreys, a primitive jawless fish that does not have paired side fins.
. . Sharks and lampreys belong to groups of fish that diverged many millions of years ago, so the new finding suggests genes important for the development of fins, and eventually limbs, were in place long before the different kinds of fishes evolved and went their separate ways.

July 25, 06: Researchers say they have discovered a new type of cricket in the Grand Canyon-Parashant National Monument, located in a remote strip of land on the Utah-Arizona border. "Finding a new species is one thing, but finding a new genus is beyond my wildest dream", Kyle Voyles, a state of Arizona cave coordinator said.
. . What makes the yet-to-be-named new genus of cricket special is that it has pincers on its hind end. The pincers are functional, but it is not known why they have them nor what purpose they serve.

July 25, 06: Language centers in the brains of rhesus macaques light up when the monkeys hear calls and screams from fellow monkeys, researchers said in a study that suggests language skills evolved early in primates.
. . Positron emission tomography detects active cells and can be used to see which parts of the brain are working. Researchers who scanned the brains of monkeys while playing them various sounds found the animals used the same areas of the brain when they heard monkey calls as humans do when listening to speech. The finding suggests that early ancestors of humans possessed the brain structures needed for language before they developed language itself.
. . "This ... brings us closer to understanding the point at which the building blocks of language appeared on the evolutionary timeline", said Dr. James Battey. "While the fossil record cannot answer this question for us, we can turn to the here and now --through brain imaging of living nonhuman primates-- for a glimpse into how language, or at least the neural circuitry required for language, came to be."
. . "This finding suggests the possibility that the last common ancestor of macaques and humans, which lived 25 to 30 million years ago, possessed key neural mechanisms (that may have been used) ... during the evolution of language", the researchers wrote. "Although monkeys do not have language, they do possess a repertoire of species-specific vocalizations that --like human speech-- seem to encode meaning in arbitrary sound patterns."
. . For instance, many species of monkeys have calls to warn of danger from above, such as an eagle, calls referring specifically to leopards and also have various sounds used while socializing.

July 24, 06: New findings raise the interesting possibility that the step from a tree-dwelling ape to a terrestrial biped might not have been as drastic as previously thought. Scientists find muscles gibbons use for climbing and swinging through trees might also help the apes run.
. . Humans are the upright apes, but much remains unknown as to how our ancestors first found their footing. While bonobos are our closest relatives and probably have a similar anatomy to our ancestors, gibbons are the most bipedal nonhuman apes, and the researchers wanted to see whether their gaits resembled any of humans.
. . Walking saves energy by converting the kinetic energy from a step to potential energy as walkers move over their supporting feet, energy that is ready to get recovered back as kinetic energy when walkers move into their next step. Running, on the other hand, stores energy from each bound as elastic energy in the tendons, muscles and ligaments before it gets recycled back as recoil for the next step.
. . Most legged animals walk at low speeds --and run, trot, hop or gallop at high speeds. By monitoring how much force the gibbons stepped down with, the researchers calculated that gibbons almost always seemed to bounce along using the energetics linked with running, even though their footfall patterns were more like those of walks, the scientists reported.
. . The bouncy energetics of running makes sense for tree-dwellers, since the stiff-legged motions often associated with walking can shake the unsteady branches the apes might find themselves on.

July 24, 06: cacti evolved a whole suite of adaptations to survive living in the desert", said plant evolutionary biologist Erika Edwards, who recently determined that the Pereskia genus of leafy shrubs and trees were the first plants to exhibit some of these water-saving traits, about 20 million years ago.
. . All plants have stomata, little pores in their skin that open and close to collect CO2. During photosynthesis, plants turn the collected CO2 into food in the form of sugars. The process is troublesome in the desert because water escapes from the pores each time they open.
. . While most plants open up their stomata during the day, cacti and other nocturnal plants such as the agaves and aloes open their pores at night. The cooler temperatures, lack of sun, and calmer breezes help cacti retain water. But in the dark, cacti can't use the sun's energy needed to make sugars out of CO2, so the hardy plants must store the CO2 for the next day. Once the sun rises, the plant goes to work making sugars.
. . Cacti have also developed succulent tissue, waxy skin, prickly spines, and a specialized root system to take every advantage in their harsh ecosystems.
. . * The stem acts as a reservoir; the plant will expand and contract depending on the amount of water it holds.
. . * The skin's waxy coating helps retain moisture.
. . * The pointy spines protect against thirsty animals looking for a free drink.
In some cacti, spines also collect rainwater and funnel precious drops to the plant's roots. You might think cacti would grow deep roots to search for a constant supply of groundwater. Instead, they often develop extensive, shallow root systems that sit just under the surface of the Earth and can extend several feet away from the plant, ready to absorb as much water as possible. When it rains, cacti shoot out more roots. During dry periods, roots will shrivel up and break off to conserve the plant's water supply. "The cactus becomes more hydrated than the soil it's growing in."

July 21, 06: A Montana State University student unearthed the skull of a baby Triceratops last week. Horner said the fossil is only the third of its kind ever to be discovered. He said he believes the Triceratops was less than a year old when it died about 65.51 million years ago.

July 21, 06: Scientists reported today what they said was the first scientific evidence that people unconsciously gesture with their voices. "This is an aspect of language that has never been explored", and one that could shed insight into the way that people think, said Howard Nusbaum, chairman of the Department of Psychology at the University of Chicago.
. . Nusbaum coauthored a paper in the Journal of Memory and Language that reported on a group of experiments said to provide the first evidence of "analog acoustic expression" --people unconsciously modulating their voices in ways that provide an additional channel of expression understood by others.
. . He added in an interview the phenomenon probably exists across all languages, although it may be shaped in the same way that different languages help determine physical gestures.
. . It would be difficult to determine if such verbal gestures played a role in evolution, he said, although one speculative piece of research has concluded gestures preceded language.

July 21, 06: To avoid becoming snake food, early mammals had to develop ways to detect and avoid the reptiles before they could strike. Some animals evolved better snake sniffers, while others developed immunities to serpent venom when it evolved. Early primates developed a better eye for color, detail and movement and the ability to see in three dimensions—traits that are important for detecting threats at close range.
. . Scientists had previously thought that these traits evolved together as primates used their hands and eyes to grab insects, or pick fruit or to swing through trees, but recent discoveries from neuroscience are casting doubt on these theories.
. . Snakes were already around when the first mammals evolved some 100 million years ago. The reptiles were thus among the first serious predators mammals faced.
. . The improved vision of primates, combined with other snake-coping strategies developed by other animals, forced snakes to evolve a new weapon: venom. This important milestone in snake evolution occurred about 60 million years ago.
. . "The [snakes] had to do something to get better at finding their prey, so that's where venom comes in", Isbell said. "The snakes upped the ante and then the primates had to respond by developing even better vision." Once primates developed specialized vision and enlarged brains, these traits became useful for other purposes, such as social interactions in groups.
. . Primates are among the few animals whose eyes face forward (most animals have eyes located on the sides of their heads). This so-called "orbital convergence" improves depth perception and allows monkeys and apes, including humans, to see in three dimensions. Primates also have better color vision than most animals and are also unique in relying heavily on vision when reaching and grasping for objects.
. . One of the most popular ideas for explaining how these traits evolved is called the "visual predation hypothesis." It proposes that our early ancestors were small, insect eating mammals and that the need to stalk and grab insects at close range was the driving force behind the evolution of improved vision.
. . Another popular idea, called the "leaping hypothesis", argues that orbital convergence is not only important for 3D vision, but also for breaking through camouflage. Thus, it would have been useful not only for capturing insects and finding small fruits, but also for aiming at small, hard-to-see branches during mid-leaps through trees.
. . But there are problems with both hypotheses, Isbell says. First, there is no solid evidence that early primates were committed insectivores. It's possible that like many primates today, they were generalists, eating a variety of plant foods, such as leaves, fruit and nectar, as well as insects.
. . More importantly, recent neuroscience studies do not support the idea that vision evolved alongside the ability to reach and grasp. Rather, the data suggest that the reaching-and-grasping abilities of primates actually evolved before they learned to leap and before they developed stereoscopic, or 3D, vision.

July 20, 06: Snakes may make people jump for a good reason --human close-up vision may have evolved specifically to spot the reptiles, researchers reported.
. . Humans, monkeys and other primates have good color vision, large brains, and use their vision to guide reaching and grasping. But while some scientists believe these characteristics evolved together as early primates used their hands and eyes to pick fruit and other foods, Lynne Isbell, a professor of anthropology at the University of California Davis, believes they may have evolved to help primates evade snakes. Neurological studies show the structure of the brain's visual system seems to be well connected to brain structures involved in vigilance, fear and learning, she said. "A snake is the only predator you really need to see close up. If it's a long way away, it's not dangerous."
. . Mammals evolved about 100 million years ago and fossils of snakes with mouths big enough to eat those mammals appear at about the same time, she pointed out. Other predators such as big cats, and hawks and eagles, evolved later. And then venomous snakes evolved about 60 million years ago, which forced primates to get better at detecting them. "There's an evolutionary arms race between the predators and prey. Primates get better at spotting and avoiding snakes, so the snakes get better at concealment, or more venomous, and the primates respond."
. . There are no dangerously venomous snakes on Madagascar, and lemurs, which only live on that large island and which have poor eyesight, have not evolved much in other ways in the past 60 million years, either.

July 20, 06: U.S. and German scientists today launched a two-year project to decipher Neandertals' genetic code, a feat that they hope will help deepen understanding of how modern humans' brains evolved.
. . "By having Neandertal [results], we'll really be able to home in on the small percentage of differences that gave us higher cognitive abilities", he said. "Neandertal is going to open the box. It's not going to answer the question, but it's going to tell where to look to understand all of those higher cognitive functions."
. . Over two years, the scientists aim to reconstruct a draft of the 3 billion building blocks of the Neandertal genome --working with fossil samples from several individuals. They face the complication of working with 40,000-year-old samples, and of filtering out microbial DNA that contaminated them after death.
. . About 5% of the DNA in the samples is actually Neandertal DNA, Egholm estimated, but he and Rothberg said pilot experiments had convinced them that the decoding was feasible.

July 18, 06: The triangular delta-wing shape found on many modern fighter jets was used by a small reptile to glide between trees 225 million years ago, a new study suggests.
. . Sharovipteryx mirabilis is known from only a single fossil. It was about 20 cm long, weighed ~40 grams and lived during the late Triassic, a time when the first dinosaurs were still evolving. Scientists knew that S. mirabilis had a membrane stretched across its hind legs, which allowed it to glide, but the exact shape of this membrane and the way it was attached to the animal's body has been debated.
. . In a new study, Gareth Dyke, a paleontologist at the University College Dublin in Ireland, and colleagues used wind-tunnel data from modern flying lizards and computer modeling to propose a new membrane configuration for S. mirabilis, one they say is unique because it is grounded in aerodynamics.
. . Alternative reconstructions of the wing membrane of Sharovipteryx mirabilis. The last one, D, is the delta-wing shape envisioned by Dyke and his team. The creature was previously the only known flying vertebrate to have a flight system dominated by its hind limbs, but the new study suggests it was also the world's first and only known delta-wing glider.
. . The new reconstruction suggests S. mirabilis had not one, but two delta wings. The creature's forelimbs likely supported a triangular membrane as well. Splayed out, the creature would have looked roughly like a drawing of a two-tiered Christmas tree, with a small triangular membrane on top attached to its forelimbs, and a larger one stretched out across its hind limbs.
. . The finding could also have implications for theories about how flight evolved in pterosaurs, another ancient flying reptile that some scientists have speculated S. mirabilis was an early ancestor of. Unlike S. mirabilis, however, the wing membranes of pterosaurs attached to their forelimbs and hind limbs. "If [S. mirabilis] was an ancestral form for pterosaurs, then unlike birds and bats, which have a forelimb-dominated flight system, the pterosaur condition may have evolved from a hind-limb dominated flight system."

July 18, 06: Once upon a time, a 2-ton wombat lumbered across the Australian Outback. Around the same time, mammoths and saber-toothed tigers had the California coastline all to themselves. Millions of years before any of these animals existed, Tyrannosaurus rex and other colossal dinosaurs ruled the world.
. . These and some of the other largest and most fantastic creatures ever to walk the planet are long gone, victims of mass extinctions of large beasts. And for reasons poorly understood, often the animals to fill the voids were tiny by comparison.
. . Scientists generally accept that a giant planetisimal slammed into the Gulf of Mexico some 65.51 million years ago, setting off a chain of catastrophic events that ultimately led to the extinction of dinosaurs. Whether or not an planetisimal is to blame, the so-called KT boundary in the fossil record displays a mass extinction of dinosaurs and other large animals around the world.
. . Small scavenging mammals and birds survived the event, and scientists can't say for sure why dinosaurs did not. Since bigger beasts couldn't take shelter in small protected burrows, perhaps they were done in by fierce environmental conditions. Or maybe with so many plants dying off, big herbivores simply had nothing to eat, and as they died out, so did the big carnivores.
. . Or perhaps with all the stress, dinosaurs simply couldn't reproduce quickly enough to keep up with sexually nimble mammals and were soon outnumbered. Then mammals got bigger. And eventually they paid the price.
. . Several mammoths and other big mammals died off during the Pleistocene/Holocene extinction event, which started around 50,000 years ago and continued through the end of the last major ice age about 10,000 years ago.
. . Today's large mammals --often with small populations, long gestation periods and late weaning ages-- are similarly predisposed to sudden mass extinction, scientists say. For big beasts, taking care of offspring is typically a time sink and an energy drain, and the whole setup makes the young highly susceptible to predation. Mass extinctions occur with surprisingly regularity over the long haul. During the last 250 million years, there's been a big die-off roughly every 26 million years.
. . Adam Lipowski, a researcher at Adam Mickiewicz University in Poland, suggests the extinctions might sometimes be driven not by climate change or impacts from space, but by the emergence of super predators.
. . In 2005, Lipowski developed a computer simulation representing a population of many species competing for food and living space. Much of the time, "medium efficiency" predators prowled the virtual world and their numbers fluctuated only slightly in response to changes in prey population size.
. . But every so often, mutations would lead to the evolution of a super predator that quickly devours an entire prey population, which in turn leads to its own extinction. The critters that survived the "predatory apocalypse" gradually mutated to fill new ecological niches, and the cycle began anew. Humans could be considered today's super predators. Humans can also initiate extinctions inadvertently.
. . Between 55,000 and 45,000 years ago, humans first set foot on Australia. At the time, large emu-like terrestrial birds and oversized wombats roamed the continent. But when humans started setting fires to clear land or flush prey from bushes, they also stripped the land of many of the plants the large animals favored.
. . Many of the smaller animals that adapted to eat the remaining plants survive today, while the two-ton wombat is no more.

July 14, 06: In "The Origin of Species", Charles Darwin discussed geographic features that could serve as "impassable" barriers to marine organisms living in shallow waters. One of the examples he gave was a 2,500- to 4,300-mile expanse of deep water that comes between the eastern and central Pacific Ocean.
. . For decades, scientists failed to find any marine species hardy enough to make the trek across the long, cold and dark divide. Then about 10 years ago, Harilaos Lessios of the Smithsonian Tropical Research Institute (STRI) documented a first exception—two species of sea urchins that successfully make the crossing. Now he has confirmed another exception—18 species of reef fish.
. . Lessios' analysis of certain reef fish with similar body types, including two species of puffer fish and three species of parrot fish, on both sides of what is called the Eastern Pacific Barrier, shows they are genetically related. This indicates that the great divide is less impenetrable than thot.
. . Other types of reef fish found to make it across the divide include three species of surgeon fish, two species of wrass, and one species each of trigger fish, hawk fish, pipe fish, goat fish, squirrel fish, chub, Big Eye and Moorish idol.
. . The reef fish, which generally live in shallow coastal waters, make it across this deep ocean expanse in the larval stage when they are swept along most likely by El Nino and La Nina currents, periodic movements of water that move faster than the region's normal currents. The El Nino currents transport larva eastward, while La Ninas carry them westward.

July 13,06: Moms Prefer Smell of Their Own Baby's Poop. Scientists find that moms consistently rank the stink of their baby's "number two" as No. 1.

July 13,06: A major midlife crisis came early for dinosaurs in the tyrannosaur family, as new research suggests many of the giant beasts died just as they reached their sexual prime. Like modern long-living birds and mammals, T. rex and other tyrannosaur species experienced high mortality rates as infants and young adults, with just a choice few surviving to maturity.
. . Researchers recently investigated a quarry in Alberta, Canada where in 1910 several fossilized specimens were found of the species Albertosaurus sarcophagus, a member of the tyrannosaur family. The collection of 22 dinos, which range from 6 to 30 feet long, remains the best evidence that tyrannosaurs were gregarious animals living in packs.
. . Scientists think the albertosaurs in this pack died at roughly the same time, providing a "frozen-in-time" look at the population. In the new work, led by Gregory Erickson of Florida State University, researchers examined the leg and foot bones of albertosaurs aged 2 to 28 to determine how mortality rate changed over the dinosaur's life span.
. . The survivorship pattern was remarkably similar to large mammals, such as buffalo, Bison, elephants, and seals, with a particularly high mortality rate in the first two years of life.
. . Mortality rates increased dramatically to more than 23% a year as the beasts reach 13 to 16 years of age. But this doesn't make sense, said Erickson, because this is just when the animals were reaching their physical and sexual prime. As with some modern animals, the stress of sex could be what did in these teenage dinos.
. . The find likely extends to non-tyrannosaur species too, Erickson said. Museum collections are much richer in herbivorous dinosaurs than the large carnivores, and species such as duckbills, for which hundreds of fossils have been recovered, would be a good one to start with to determine the life history of other dinosaurs.

July 13,06: Forget cute, cuddly marsupials. A team of Australian paleontologists say they have found the fossilized remains of a fanged killer kangaroo and what they describe as a "demon duck of doom."
. . A University of New South Wales team said the fearsome fossils were among 20 previously unknown species uncovered at a site in northwest Queensland state. Professor Michael Archer said the remains of a meat-eating kangaroo with wolf-like fangs were found as well as a galloping kangaroo with long forearms that could not hop like a modern kangaroo. "Because they didn't hop, these were galloping kangaroos, with big, powerful forelimbs. Some of them had long canines (fangs) like wolves."
. . Vertebrate paleontologist Sue Hand said modern kangaroos look almost nothing like their ferocious forebears, which lived between 10 million and 20 million years ago. The species found at the dig had "well muscled-in teeth, not for grazing. These things had slicing crests that could have crunched through bone and sliced off flesh", Hand said.
. . The team also found prehistoric lungfish and large duck-like birds. "Very big birds ... more like ducks, earned the name 'demon duck of doom', some at least may have been carnivorous as well", Hand said.
. . Archer said the team was studying the fossils to better understand how they were affected by changing climates in the Miocene epoch between 5 million and 24 million years ago.

July 13,06: Finches on the Galapagos Islands that inspired Charles Darwin to develop the concept of evolution are now helping confirm it --by evolving.
. . A medium sized species of Darwin's finch has evolved a smaller beak to take advantage of different seeds just two decades after the arrival of a larger rival for its original food source. The altered beak size shows that species competing for food can undergo evolutionary change.
. . It's rare for scientists to be able to document changes in the appearance of an animal in response to competition. More often it is seen when something moves into a new habitat or the climate changes and it has to find new food or resources.
. . In 1982, a breeding population of large ground finches, Geospiza magnirostris, arrived on the island and began competing for the large seeds of the Tribulus plants. G. magnirostris was able to break open and eat these seeds three times faster than G. fortis, depleting the supply of these seeds.
. . In 2003 and 2004, little rain fell, further reducing the food supply. The result was high mortality among G. fortis with larger beaks, leaving a breeding population of small-beaked G. fortis that could eat the seeds from smaller plants and didn't have to compete with the larger G. magnirostris for large seeds.
. . That's a form of evolution known as character displacement, where natural selection produces an evolutionary change in the next generation, Grant explained.

July 13,06: Meerkats actively teach their young how to catch and eat their prey, British researchers said in a study that is one of the first to prove that animals show such complex behavior.
. . While animals are known to learn from one another by watching, the team at Britain's University of Cambridge said they had demonstrated that the animals actually teach, as defined by clear principles.
. . Older meerkats will bite the stinger off a live scorpion and give it to a youngster to kill and eat, and if the pup fails to do the job before the prey can crawl away, will nudge it back. Older meerkats --not necessarily the parents-- will watch youngsters to see how they are doing.
. . Meerkats are a type of mongoose and live in groups of three to 40 in dry regions of southern Africa. Each group includes a dominant male and female who produce 80% of the pups, and older animals that help to watch over and rear the young. The animals rely on hard-to-catch prey such as grasshoppers, and various species of scorpions, including poisonous ones.
. . The meerkats demonstrate clearly that they teach, and do not merely allow the pups to learn by observing, Thornton and McAuliffe said. "A greater understanding of the evolution of teaching is essential if we are to further our knowledge of human cultural evolution and for us to examine the relations between culture in our own species and cultural behavior in other animals", Thornton said.

July 10, 06: A new study helps answer a longstanding dinosaur mystery by revealing that the largest dinosaurs could likely maintain warm body temperatures while their smaller cousins were probably more similar to modern cold-blooded reptiles.
. . Scientists have debated the body temperature of dinos for years, mainly whether the beasts were cold-blooded ectotherms, like reptiles, or warm-blooded endotherms, like mammals and birds.
. . A third hypothesis is that similar to modern day alligators, Galapagos tortoises, and Komodo dragons, large dinosaurs relied on a process called thermal inertia to maintain a body temperature several degrees warmer than the environment.
. . Thermal inertia is a body's ability to conduct and store heat that is generated either through metabolism or moving around. Large animals are typically well equipped for this mechanism because of their low body surface to body volume ratio. For example, an elephant loses heat at a slower rate than a mouse.
. . As suspected, the model revealed that body temperature increased with body size for seven species and that the largest dinosaurs had relatively constant body temperatures—similar to modern warm-blooded creatures --and they kept their heat up through thermal inertia.
. . The model shows that a small, 26-pound dino would have a body temperature of roughly 77 degrees F. A 14-ton beast, however, ran a temperature around 105.8 degrees Fahrenheit. The largest dinosaur in the study, Sauroposeidon proteles, weighed in at about 60 tons and had a body temperature, the study suggests, of about 118 degrees F, which is just past the upper temperature limit for most animals, leading the researchers to suggest that extremely high body temperatures might have been the only thing preventing dinosaurs from growing even larger.
. . Dinosaurs likely got warmer as they became adults. A 661-pound adult dino probably ran a temperature 37 degrees F warmer than as a juvenile, the scientists conclude. The difference was even greater for a 27-ton Apatosaurus, which was 68 degrees F warmer as an adult. [also see /dinodata.html]

July 10, 06: The high-pitched whine of a mosquito might drive you nuts, but it's music to the ears of these little pests.
. . Scientists have long known that male mosquitoes key in on the buzzing of females to help them find a partner. But a new study finds that female mosquitoes, despite their comparatively simple antennae, are among the best listeners in the insect world.
. . The research also revealed how the mosquito mating commences. When two mosquitoes approach each other --typically moving along at about 1 mph-- each alters the tone of its buzzing, which is created by the wings beating at up to 600 times each second. If the tones converge, each knows the other is a potential mate. If the tones diverge dramatically, then they learn they're chasing a same-sex relationship.
. . It is likely, the researchers say, that different mosquito species (there are about 3,000 of them around the world) employ different flight tones in order to recognize viable mates.

July 10, 06: Social contact helped the Ebola virus virtually wipe out a population of gorillas in Congo, French researchers reported. A 2004 outbreak of the virus, which also kills people, killed 97% of gorillas who lived in groups and 77% of solitary males.
. . It also may shed light on how early humans evolved, they suggested. The findings may show that pre-humans were slow to live in large social groups because disease outbreaks could wipe out those who did.
. . Ebola hemorrhagic fever is one of the most virulent viruses ever seen, killing between 50% and 90% of victims. The World Health Organization says about 1,850 people have been infected and 1,200 have died since the Ebola virus was discovered in 1976. WHO and other experts say people probably start outbreaks when they hunt and butcher chimpanzees. The virus is transmitted in blood, tissue and other fluids.

July 9, 06: Why do gorillas eat rotten wood? The answer: for the sodium. [you realize: when they say sodium, they don't mean sodium; they mean salt, which is a *totally different thing. Sodium reacts VIOLENTLY with water.]
. . Gorillas in the Bwindi Impenetrable National Park in Uganda will suck on wood chips for several minutes before spitting them. Sometimes they chew on them until their gums bleed. They have also been seen licking the bases of tree stumps and the insides of decayed logs, and breaking off pieces of wood to munch on later. Gorillas will return daily to the same stump and take turns feeding.
. . The researchers analyzed these items for their salt content and found that the decayed wood was the source of over 95% of the animal's dietary salt, even though it represented only about 4% of their wet weight food intake.
. . The behavior has been observed in other primates, too, including chimpanzees, lemurs and mountain monkeys. Other animals also have been known to go to strange lengths to satisfy their salt cravings. Elephants travel to underground caves for salt deposits, moose eat aquatic plants with high salt content and colobus monkeys compliment their diets with the leaves and bark of Eucalyptus, a plant rich in salt.

July 10, 06: A researcher named Svante Pääbo at Germany’s Max-Planck Institute for Evolutionary Anthropology published the results of an early effort to read Neandertal DNA. Pääbo and his team examined mitochondrial DNA –-tiny loops of genetic material found in the hundreds of power plants that exist in each cell. Unfortunately, they just don’t contain that much information. Nonetheless, when Pääbo and his team announced that no Neandertal mitochondrial DNA had found its way into Homo sapiens, the press and scientific community went wild.
. . In California, geneticist Eddy Rubin stands surrounded by huge glass tanks. Inside, robotic arms move with frenetic precision over plates holding genetic material, reducing the Neandertal’s remains to tiny strings of nucleotides and producing the world’s first extended sequence of Neandertal DNA. The data will help pinpoint when humans and Neandertals diverged on the evolutionary tree and if they bore children together when they met again as separate species.
. . This process was impossible just a few years ago, before computers as fast as Rubin’s and vast databases of gene sequences.
. . His first major conclusion is that humans and Neandertals diverged into recognizably separate groups about 500,000 years ago, a date anthropologists have long sought to pin down.
. . But that’s not all. "The evidence suggests very strongly that Neandertal men didn’t pass on any genetic material to modern humans." The Neandertal DNA is simply too different from our own.
. . If he had a complete genome, he could look for genes like FOXP2, which is found in songbirds and humans and is associated with the complex vocalizations that are the hallmark of language. And he wants to hunt for unique Neanderthal mutations in genes like AHI1, which is connected to brain development.

July 7, 06: Scientists have identified a new species of ancient aquatic reptile that swam the seas when dinosaurs still ruled the Earth. Dubbed Umoonasaurus, the creature lived in waters off the coast of what is now Australia 115 million years ago, when the continent was located much closer to Antarctica than it is now.
. . Plesiosaurs were large marine reptiles that had stocky, barrel-shaped bodies, short tails and paddle-like limbs. Some had long, slender necks, while others had short, squat ones. What made Umoonasaurus stand out from other plesiosaurs were a series of high, thin crests on its head and numerous fused vertebrae at the end of its tail that might have supported a small tail fin. "They were the killer whale equivalent of the Jurassic."
. . Umoonasaurus grew to only about 8 feet and had a small skull perched atop a slender, stalk-like neck. Umoonasaurus outlasted many plesiosaur species and was among of the last of its kind. It lived during the twilight of the dinosaurs' reign, before the planet experienced one of the most famous, though not the worst, known mass extinctions.
. . Fossils of Umoonasaurus have been found in Australian opal mines for years, ever since the late 1960s, but it was only last year with fresh analyzes that the creature was recognized as being a unique species.
. . For much of its geologic history, Australia was a southern polar continent. It's only been in the past 50 million years or so that Australia drifted north. During the Cretaceous period when Umoonasaurus lived, the continent was located at about 70 degrees south latitude.
. . Presumably, the sea creature had developed a way to cope with the low water temperatures. Kear and his team speculate that the beasts might have been warm-blooded like mammals and able to regulate their core body temperatures, or that they might have taken part in seasonal migrations like modern whales.

July 5, 06: Museum dioramas typically portray mammoths as having shaggy brown coats, but some of the hairy beasts might have been blonde, raven-haired or red-bodied in real life, thanks to a gene that controls hair color in humans and other mammals.
. . By examining DNA extracted from a mammoth bone frozen in Siberian permafrost and comparing it with sequences from other mammoth remains, researchers have concluded that the wooly creatures probably carried two versions of Mc1r, a gene whose protein product helps determine hair color in several mammals, including humans, mice, horses and dogs.
. . Mammoths with the partially active version of Mc1r would likely have had light-colored coats, the researchers say, while those with the active version would have had dark hair. If the mammoth gene works the same way that it does for humans and other mammals, the lighter animals might have had yellow or reddish hair, while the dark ones might have been black or brown. [Seems to me the most northern ones wuda been evolving toward white, like all polar mammals.]

July 5, 06: Cramped housing conditions and air pollution in Athens have given rise to a "super breed" of mosquito that is larger, faster and more adept at locating human prey, a Greek daily has reported. Athens-based mosquitoes can detect humans at a distance of 25-30 meters (yards) and also distinguish colors, unlike their color-blind counterparts elsewhere.
. . They also beat their wings up to 500 times a second --compared to 350 beats for other variations-- and are larger by 0.3 micrograms, on average.

July 5, 06: "A primary claim among raw food advocates is that the raw diet is a natural diet. After all, no other animal cooks its food, and humans only started cooking after the domestication of fire. But "natural" is always a dangerous word. Humans have evolved to eat and survive on a wide range of diets. The Inuit have survived thousands of years almost entirely on a diet of raw fish and meat. Some cultures, conveniently in regions of prolonged growing seasons, shun all meat as unnatural.
. . That said, humans have always eaten some cooked food. So, too, do many land animals; and so did our human ancestors. How? Largely in the form of roasted grasshoppers or other small critters caught in forest fires and brushfires. Fire foraging was quite natural and helped secure our survival. This is how we developed the taste for cooked food.
. . Another main claim by raw food advocates is that heat (from cooking) destroys enzymes in the food. Enzymes are proteins that serve as catalysts for specific biochemical reactions in the body. There are indeed many forms of enzymes. There are plant enzymes, digestive enzymes and metabolic enzymes, for example. And, yes, heat can destroy enzymes.
. . But plant enzymes, which raw dieters wish to preserve, are largely mashed up with other proteins and rendered useless by acids in the stomach. Not cooking them doesn't save them from this fate. Anyway, the plant enzymes were for the plants. They helped with the plants' growth, and they are responsible for the wilting and decomposition of plants after they are harvested. They are not needed for human digestion. Human digestive enzymes are used for human digestion.
. . Raw foods certainly aren't safer than cooked food, as some claim. Most commercial chicken and a good deal of beef and pork, sadly, are loaded with bacteria and parasites. Cooking kills this.
. . Major and surprising sources of food-borne illness, however, are raw sprouts, green onions and lettuce. These must be washed thoroughly before consumption. Raw (unpasteurized) milk is dangerous and mostly illegal to buy; trust your source. Raw (sprouted) kidney beans and rhubarb are poisonous.
. . One needs to question why a so-called natural diet leaves the dieter dependent on pills for B12 (impossible to get without animal products, such as meat or eggs) or zinc (very hard to get on a raw diet).
. . Like the raw food diet, adherents believe a macrobiotic lifestyle can prevent and even cure cancer, and this was promoted in the United States by Aveline Kushi, who died of cancer.
. . The macrobiotic diet is one of the healthiest around, actually, despite the strange philosophical baggage that accompanies it. And Americans would be a far healthier lot if we subscribed to it to some degree. Similarly, we should welcome the take-home message of the raw food diet: Eating fresh vegetables, sprouts, nuts and seeds is good for you. But lighten up and light up the stove."

July 3, 06: Taiwan, Malaysia and Siberia all are likely locations. He —or she— did nothing more remarkable than be born, live, have children and die. Yet this was the ancestor of every person now living on Earth — the last person in history whose family tree branches out to touch all 6.5 billion people on the planet today. That means everybody on Earth descends from somebody who was around as recently as the reign of Tutankhamen, maybe even during the Golden Age of ancient Greece. There's even a chance that our last shared ancestor lived at year 0 CE.
. . "It's a mathematical certainty that that person existed", said Steve Olson, whose 2002 book "Mapping Human History" traces the history of the species since its origins in Africa more than 100,000 years ago. Furthermore, Olson and his colleagues have found that if you go back a little farther --about 5,000 to 7,000 years ago-- everybody living today has exactly the same set of ancestors. In other words, every person who was alive at that time is either an ancestor to all 6 billion people living today, or their line died out and they have no remaining descendants.
. . It also means that all of us have ancestors of every color and creed. Every Palestinian suicide bomber has Jews in his past. Every Sunni Muslim in Iraq is descended from at least one Shiite. And every Klansman's family has African roots.
. . It's simple math. Every person has two parents, four grandparents and eight great-grandparents. Keep doubling back through the generations —16, 32, 64, 128— and within a few hundred years, you have thousands of ancestors.
. . In fact, most of the people who lived 1,200 years ago appear not twice, but thousands of times on our family trees, because there were only 200 million people on Earth back then. Simple division --a trillion divided by 200 million-- shows that on average, each person back then would appear 5,000 times on the family tree of every single individual living today.
. . Keep going back in time, and there are fewer and fewer people available to put on more and more branches of the 6.5 billion family trees of people living today. It is mathematically inevitable that at some point, there will be a person who appears at least once on everybody's tree.
. . But don't stop there; keep going back. As the number of potential ancestors dwindles and the number of branches explodes there comes a time when every single person on Earth is an ancestor to all of us, except the ones who never had children or whose lines eventually died out.
. . Migration is the key. When a people have offspring far from their birthplaces, they essentially introduce their entire family lines into their adopted populations, giving their immediate offspring and all who come after them a set of ancestors from far away.
. . People tend to think of preindustrial societies as places where this sort of thing rarely happened, where virtually everyone lived and died within a few miles of the place where they were born. But history is full of examples that belie that notion. Alexander the Great, the Vikings, the Mongols, and the Huns all traveled thousands of miles to burn, pillage and --most pertinent to genealogical considerations-- rape more settled populations.
. . More peaceful people moved around as well. During the Middle Ages, the Gypsies traveled in stages from northern India to Europe. In the New World, the Navaho moved from western Canada to their current home in the American Southwest. People from East Asia fanned out into the South Pacific Islands, and Eskimos frequently traveled back and forth across the Bering Sea from Siberia to Alaska.

June 29, 06: Early humans living in Africa's open savannahs probably made easy pickings for large predatory cats, but a new study suggests that at least one of the meals didn't sit well. A large cat dining on the entrails of one our early ancestors thousands of years ago contracted an ulcer-causing bacteria that spread to lions, cheetahs and tigers and which persists to this day, a new study concludes.
. . Helicobacter pylori are bacteria that cause chronic stomach pains and ulcers in humans. Other animals, including non-human primates, are infected by other Helicobacter species that are only distantly related to H. pylori. The one exception is H. acinonychis, a microbe that infects large felines such as lions, tigers and cheetahs.
. . The microbes responsible for ulcers in humans and big cats are so similar that scientists speculated they were once one species. According to this theory, the microbe diverged after either a human ate a cat infected with the ulcer-causing bacteria or a cat ate an infected human.
. . To determine who or what ate whom, the researchers compared the genomes of the two bacteria species. They found that many of the inactive genes in H. acinonychis, the species that infects large cats, are more fragmented, or broken, than their still-functioning counterparts in H. pylori. This strongly suggests that the direction of the host jump was from humans to cats, and not the other way around.
. . Based on similarities in the genomes of the two bacteria species, the researchers estimate that the host jump from humans to large cats took place about 200,000 years ago.

June 29, 06: Ants use an internal pedometer to find their way home without getting sidetracked, a new study reports. Desert ants on foraging expeditions use celestial cues to orient themselves in the homeward direction, but with few landmarks in the barren land, scientists have wondered how the insects always take the most direct route and know exactly how far to march. The new study reveals that counting their steps is a crucial part of the scheme.
. . The researchers glued stilt-like extensions to the legs of some ants to lengthen stride. The researchers shortened other ants' stride length by cutting off the critters' feet and lower legs, reducing their legs to stumps. By manipulating the ants' stride lengths, the researchers could determine whether the insects were using an odometer-like mechanism to measure the distance.
. . The ants on stilts took the right number of steps, but because of their increased stride length, marched past their goal. Stump-legged ants, meanwhile, fell short of the goal. After getting used to their new legs, the ants were able to adjust their pedometer and zero in on home more precisely, suggesting that stride length serves as an ant pedometer.

June 27, 06: In just a second or two, a giraffe can lift its head from ground level to the sky, some 15 feet up, and never get a head rush. "If we did that we'd certainly faint." A giraffe's head fills with blood when it is near the ground, and blood pressure there doubles. When the beast raises its head up for a bite in the trees, the blood drains out.
. . Scientists once thought that vessels in the giraffe's neck siphoned blood from the heart to the brain. However, Mitchell's research suggests getting the blood to the brain of an erect giraffe involves a powerful pump and very high blood pressure—twice as high as ours.
. . Giraffes have big hearts, weighing up to 12 kg (26#). When a giraffe lifts its head, blood vessels in the head direct almost all of the blood to flow to the brain, and not to other parts of the head such as their cheeks, tongue, or skin. At the same time, the animal's thick skin and an unusual muscle in the jugular vein --veins don't normally have muscles—- add pressure to the vein, which carries blood from the head back to the heart.

June 27, 06: Biologists working in the forests of Borneo have found a previously unknown type of snake which can change its color spontaneously like a chameleon, the environmental body WWF said. They said although some reptiles with legs, like the chameleon lizard, had the ability to change color, it was rare for snakes.
. . The poisonous snake, about half a meter long, was discovered in the wetlands and swamp forests of Betung National Park in the Indonesian part of the island, which is also shared by Malaysia and Brunei. When picked up and put in a bucket, it was reddish-brown but later changed its color to white, apparently in an automatic reaction to blend in with surroundings. [obviously, it's both predator and prey.]

June 23, 06: The classic spider's web, like Charlotte would have woven, was invented just once, way back in the Cretaceous period some 136 million years ago, scientists report. Called an orb web, it's the generally circular style spun by two major types of spiders, which had raised the possibility of the two groups evolving this form separately.
. . But a paper says a comparison of the spider genes related to web making shows that the orb web developed just once. While the two groups probably developed orb-web spinning from a common ancestor, they came up with different ways of making the web catch prey.
. . Araneoid webs have glue droplets that make prey stick to the web, while deinopoids wrap their threads with a different type of silk fiber that "the spiders comb, until it almost has the appearance of Velcro under a microscope, and they snag insects that way", Garb reported.
. . Not all spiders make orb webs. The black widow, for example, weaves a web that is a tangle of silk without the circular pattern.

June 21, 06: Scientists have discovered an orchid that never needs to get a date --it can fertilize itself by performing a sexual act never before seen in flowers. The hermaphroditic orchid shuns the sexual practices of other flowers and completes the deed without the help of sticky liquids, birds or even a breath of wind, a new study reveals.
. . The orchid, Holcoglossum amesianum, performs a tricky, 360-degree, gravity-defying dance to pollinate itself. While most flowers spread their pollen to other plants, the new orchid is extremely exclusive and only mates with itself. The self-pollination act was also successful in flower terms, producing fruit about 50% of the time.
. . This method of self-pollination, which comes in handy when winds are gentle or insects are lacking, adds to the variety of mechanisms flowering plants have evolved to ensure success.

June 21, 06: Fish living in coral reefs often pick up skin parasites or experience buildup of dead skin cells. To keep healthy and tidy, the fish rely on small "cleaner" fish to nibble away the parasites and detritus.
. . One common cleaner fish, the yellow, blue, and black striped Labroides dimidiatus, can choose to remove parasites from the skin of client, or they can cheat and dine on the clients mucus, the tastier option. But there is no penalty for cheating. The clients, in this study Scolopsis bilineatus, rarely eat their cleaners, even the cheaters. So scientists have long wondered why cheating isn't rampant.
. . The researchers set up an experiment where client fish could observe two cleaners, one dutifully munching away at another client's parasites and another swimming freely near another client. Taking the cleaner fishes' past performances into account, the clients chose the cooperative, hard-working fish significantly more often than the loafer.
. . The authors suggest that the client fish establish a rating system for the cleaners they observe and enlist the aid of those that score highly. The finding illustrates that complex social networks exist in the aquatic world and that this type of selective behavior could be the evolutionary roots of altruism and reputation.

June 16, 06: Each morning in the harsh African Namib Desert, where it rains less than a half an inch a year, thirsty plants and animals welcome the relief of a light fog that covers the sand dunes. Little droplets from the fog settle on the nubs of the desert beetle's shell. Water-repellent ridges border the bumps, and channel the drops toward the beetle's head.
. . "That allows small amounts of moisture in the air to start to collect on the tops of the hydrophilic bumps, and it grows into bigger and bigger droplets", said lead researcher Michael Rubner. "When it gets large, it overcomes the pinning force that holds it and rolls down into the beetle's mouth."

June 14, 06: Sperm wars! If there was a prize for biggest sperm in nature, it would go to Drosophila bifurca, a tiny fruit fly whose coiled sperm would measure more than 2 inches long if straightened out. That's 1,000 times longer than an average human sperm.
. . Along with biologist Scott Pitnick, Bjork examined why any animal, let alone a tiny fruit fly, would evolve such lengthy sperm. The pair's findings show that the answer lies in the body of the female fruit flies. In many species, the number of sperm produced by males far outnumbers the amount of eggs produced by females. The males produce tiny but numerous sperm to increase the chances that one of them will make it to the egg. As sperm outnumbers eggs, eggs become rare and precious commodities, and male competition for access to them increases.
. . Sexual selection theory predicts that as sperm get bigger and the sperm to egg ratio becomes more even, male competition should decrease. But when the researchers examined male competition in D. bifurca, they found that it wasn't weakened as expected. The reason for this, it turned out, has to do with the anatomy of the females.
. . Even after a male has successfully inseminated a female, there's still a long way to go before fertilization can take place. That's because the female bodies of many species are not passive arenas within which sperm compete, but more like obstacle courses, with hurdles and defenses in place to weed out weakling sperm.
. . For example, the female reproductive tract might release harsh chemicals harmful to sperm, or it might evolve to become intentionally long so that the race to fertilization becomes a test of sperm endurance.
. . These post-sex hurdles are part of what biologists call "female cryptic choice" since they're not obvious to researchers, or to the females themselves. In D. bifurca, the female reproductive tract is just slightly longer than the sperm that swim through it. It's coiled like a slinky.
. . "These results demonstrate the often under-appreciated power that sperm competition and cryptic female choice have over the physiological and behavioral evolution of both males and females."

June 17, 06: Scientists discovered the remains of five extremely well preserved birds, named Gansus yumenensis, preserved in rocks of a dry lake bed in China. The skeletons were uncrushed and nearly complete, although no skulls were found.
. . Also preserved were the remains of foot webbing and feathers. The webbed feet and features of the leg bones indicate the bird paddled like a modern duck and dove for its prey much like today's loons, although probably not as adeptly. This suggests that today's birds may have gotten their start lakeside. "We won't have a definitive dietary answer until we find a skull." But it strongly suggests ancestors of all living birds were waterfowl, researchers said.
. . The pigeon-sized bird probably resembled a tern or a loon. The birds had not yet evolved the hollow, air-filled bones that make modern birds to light and nimble, and it still had tiny claws at the end of its wings that probably would have made it slightly clumsy in flight.
. . "You can walk up to a rock and peel off sheet after sheet like paper until you get to a fossil."

June 22, 06: Scientists have found 136-million-year-old piece of amber encasing pieces of web and trapped insects that helps fill in the gaps of the origin of orb webs. The finding also indicates predatory spiders likely played a role in the evolution of flying insects.
. . It contains 26 web strands with a mite, a wasp leg, and a beetle stuck to some of the thread by visible droplets of web "glue." Although these insects are extinct, their size and diversity match the type of prey caught in modern webs.
. June 14, 06: Spiral orb webs, which to many people typify spiders, were catching insects in their sticky silk while the dinosaurs still walked the Earth.
. . True orb weaving spiders found trapped in amber from 121-115 million years ago are the oldest of their type yet found. The fossil spiders were found embedded in amber from Alava in northern Spain. They date to the Lower Cretaceous.
. . The spiral webs have proven an extremely successful strategy for catching prey --evidenced by the great diversity of orb weavers present today. The evolutionary success of this design can be seen in the high diversity of true orb weavers, which currently number 2,847 living species.
. . Spiders may have expanded in number and diversity during the Cretaceous. An explosion in the abundance of flowering plants begot an expansion of the insects which pollinated them. These in turn provided prey for the spiders.
. . There are fossil spiders that date from the Devonian (350-420 million years ago) - long before even the dinosaurs. In some of these mineral fossils, it is possible to see evidence of spinnerets, the organs spiders use to spin their web silk.

June 14, 06: The first pictures showing a live specimen of a rodent species once thought to have been extinct for 11 million years have been taken by a retired Florida State University professor and a Thai wildlife biologist.
. . They took video and still photographs of the "living fossil", which looks like a small squirrel or tree shrew, in May during an expedition to central Laos near the Thai border. Known as Diatomyidae, scientists have nicknamed it the Laotian rock rat. The creature is not really a rat but a member of a rodent family once known only from fossils.
. . The pictures show a docile, squirrel-sized animal with dark dense fur and a long tail but not as bushy as a squirrel's. It also shows that the creature waddles like a duck with its hind feet splayed out at an angle --ideal for climbing rocks.
. . The long-whiskered rodent was branded as a new species last year when biologists first examined dead specimens they found being sold at meat markets. But they had never seen a live animal until Redfield and Treesucon photographed it.

June 14, 06: Researchers have created a hybrid butterfly whose genes and color are blends of two other species. New species typically arise from the branching of one species into two. Scientists report the first clear evidence that evolution in animals can work the other way around, too. Hybridization is well known among plants, but scientists had thought it was rare in animals.
. . The hybrid lab butterfly was created by interbreeding two butterflies with different colored wing markings. H. cydno has black wings with white and yellow markings, while H. melpomene has black wings with red, yellow and orange markings. The lab hybrid had black wings with red and yellow markings.
. . H. cydno and H. melpomene can be found near each other in the wilds of Mexico and northern South America. Where the habitats of these two butterflies overlap, a third butterfly, called H. heurippa, is found. Interestingly, the color markings on the wing of H. heurippa are nearly identical to those of the lab-made hybrid.
. . The study supports a long-held suspicion among biologists that H. heurippa is a wild hybrid. The researchers believe it was created naturally from the interbreeding of the same two butterfly species used to create the lab hybrid.
. . In biology, fitness is a measure of an organism's ability to reproduce and thrive. For example, mules, which are the offspring of donkeys and horses, are usually sterile. Indeed, in the current experiment, females in the first generation of hybrids were sterile (males were not). It's thought that in the wild, virile H. heurippa males bred with females of one of the parent species until eventually, non-sterile female hybrids were born. This process is called "backcrossing."
. . Another obstacle scientists have thought would be difficult for hybrid species to overcome: Because hybrid animal offspring inhabit the same environments as their parent species, they wouldn't be reproductively isolated enough to form a distinct species. But in the new study, researchers found that H. heurippa butterflies show a strong mating preference to members of their own species rather than with their parent species. "If you cover the red or the yellow stripe of a bi-colored hybrid female, hybrid males no longer find her the least bit attractive."

June 13, 06: The feet of flies have two fat footpads that give the insect plenty of surface area with which to cling to ceilings. The adhesive pads on the feet, called pulvilli, come equipped with tiny hairs that have spatula-like tips. These hairs are called setae.
. . Scientists once thought that the curved shape of the hairs suggested that flies used them to grip onto the ceiling. In fact, the hairs produce a glue-like substance made of sugars and oils.
. . A research team from the German Max Planck Institute for Metals Research recently studied more than 300 species of wall-climbing insects and watched them all leave behind sticky footprints.
. . Flies need sticky feet to walk on ceilings, but not so sticky that they get stuck upside down. So each foot comes with a pair of claws that help hoist the gooey foot off the wall. Flies use several different techniques to get unstuck: pushing, twisting, and peeling its footpads free. "Methods involving peeling are always the best, because they require less energy to break the contact."
. . The research team worked with a robotics group to design robotic feet that mimic a fly's footing.

June 10, 06: A new type of hammerhead shark has been discovered in the northwestern Atlantic Ocean. It resembles a common species called the scalloped hammerhead. Genetic studies revealed that there was a second "cryptic" species - that is, "genetically distinct" from the scalloped hammerhead. There are 454 recorded species of shark.

June 10, 06: In an extreme way to beat the heat, a sand gazelle shrinks its liver and heart to cope with long periods of drought, a new study reveals.
. . The deserts of the Arabian Peninsula rank among the most severe environments in the world. The sand gazelle stands out as one of the most successful critters at dealing with this stress. "We found that gazelles had the lowest total evaporative water loss ever measured in an arid zone ungulate [hoofed animal]."
. . Organs such as the liver and heart require significant amounts of oxygen to function. By shrinking these organs, the gazelles don't have to breathe as much and thus reduce the amount of water lost by respiratory evaporation.
. . Water-deprived sand gazelles also have a higher fat content in their brains. The researchers suggest that these stores might be beneficial for fueling brain metabolism during prolonged food and water deprivation.

June 10, 06: As our yogurt culture evolves, so do the bacteria involved in making it, ridding themselves of extra genes and in the meantime giving scientists a glimpse of the evolutionary process in action.
. . Scientists have sequenced the genome of Lactobacillus Bulgaricus, a group of bacteria involved in making yogurt. Originally associated with plants, this bacteria is specializing to make itself more comfortable in its current environment: fermented milk.
. . Yogurt can be traced back to 3,200 years BCE. Looking at the genome, scientists have found traces of adaptation in a strain called L. Bulgaricus over time. "The interpretation of what we see is that this bacterium has eliminated, and still is in the process of eliminating, genes that it doesn’t need any longer", such as those involved in the metabolism of sugars of plant origin.
. . The origin of yogurt goes back to ancient Middle Eastern cultures that used it to preserve milk. The live bacteria in yogurt are thought to have many health benefits, such as prevention of certain infections, calming of lactose intolerance, and lessening diarrhea.

June 8, 06: The first support for the idea of life arising out of the primordial soup came from the famous 1953 experiment by Stanley Miller and Harold Urey, in which they made amino acids --the building blocks of proteins-- by applying sparks to a sealed test tube of hydrogen, methane, ammonia, and water.
. . If amino acids could come together out of raw ingredients, then bigger, more complex molecules could presumably form given enough time. Biologists have devised various scenarios in which this assemblage takes place in tidal pools, near hot underwater volcanic vents, on the surface of clay sediments, or even in space.
. . But were the first complex molecules proteins or DNA or something else? Biologists face a chicken-and-egg problem in that proteins are needed to replicate DNA, but DNA is necessary to instruct the building of proteins.
. . Many researchers, therefore, think that RNA—a cousin of DNA—may have been the first complex molecule on which life was based. RNA carries genetic information like DNA, but it can also direct chemical reactions as proteins do.
. . Shapiro, however, thinks this so-called "RNA world" is still too complex to be the origin of life. Information-carrying molecules like RNA are sequences of molecular "bits." The primordial soup would be full of things that would terminate these sequences before they grew long enough to be useful, Shapiro says. [But only one molecule --over millions of years-- has to survive & multiply!]
. . Instead of complex molecules, life started with small molecules interacting through a closed cycle of reactions, Shapiro argues in the June issue of the Quarterly Review of Biology. These reactions would produce compounds that would feed back into the cycle, creating an ever-growing reaction network.
. . All the interrelated chemistry might be contained in simple membranes. These might divide just like cells do, with each new bag carrying the chemicals to restart—or replicate—the original cycle. In this way, "genetic" information could be passed down.
. . Moreover, the system could evolve by creating more complicated molecules that would perform the reactions better than the small molecules. "The system would learn to make slightly larger molecules", Shapiro says. This origin of life based on small molecules is sometimes called "metabolism first" (to contrast it with the "genes first" RNA world).
. . To answer critics who say that small-molecule chemistry is not organized enough to produce life, Shapiro introduces the concept of an energetically favorable "driver reaction" that would act as a constant engine to run the various cycles.
. . A possible candidate for Shapiro's driver reaction might have been recently discovered in an undersea microbe, Methanosarcina acetivorans, which eats carbon monoxide and expels methane and acetate (related to vinegar).
. . Biologist James Ferry and geochemist Christopher House from Penn State University found that this primitive organism can get energy from a reaction between acetate and the mineral iron sulfide. Compared to other energy-harnessing processes that require dozens of proteins, this acetate-based reaction runs with the help of just two very simple proteins.

June 7, 06: Odd-shaped mounds of dirt in Australia turn out to be fossils of the oldest life on Earth, created by billions of microbes more than 3 billion years ago, scientists say in a new report. And these mounds are exactly the type of life astrobiologists are looking for on Mars and elsewhere.
. . A new study gives the strongest evidence yet that the mounds dotting a large swath of western Australia are Earth's oldest fossils. The theory is that these are not merely dirt piles that formed randomly into odd shapes, but that ancient microbes burrowed in and built them.
. . Allwood said her study made the case for life --and the first signs of biodiversity-- solidly by looking at how the stromatolites fit with the rock formations around them, with each other, and what would have been happening on Earth at that time. One of the clinchers was putting them in seven repeating subtypes, which indicates they weren't random.

June 7, 06: After years of searching, scientists have rediscovered Illacme plenipes, a millipede that is the world's leggiest creature, in a tiny patch of San Benito County, California. This type of millipede was first discovered in 1926.
. . The word millipede literally means a thousand feet. In reality, no millipede has so many. The I. plenipes, however, comes closest, with the females possessing up to 750 legs. The females, as in turned out, were not only longer at about 33mm, but also had up to 666 legs, slightly fewer than the known record holder (750). The males averaged 16mm in length and walked on no more than 402 legs.

June 7, 06: Fossils from a new species of a 150 million-year-old dwarf dinosaur have been found in northern Germany, scientists said today. Initially they suspected that the remains from more than 11 sauropods were from young dinosaurs. But an analysis of their bones showed they were small adults that probably lived on an island during the late Jurassic period --until a technique called bone microstructure revealed they were adults.
. . Sauropods were the largest animals that lived on land. With their long necks, massive tails, small heads and stout legs they weighed on average about 20 tons and measured 20 meters in length. The biggest grew to 80 tons and were as long as 40 meters. By contrast, the new dwarf species, called Europasaurus, was a mere 1 ton and about 6 meters long --about the size of a small rhinoceros or a big buffalo.
. . Dwarfism is a common phenomenon on islands --they moved as large animals to islands and shrank within a few generations because of limited resources.

June 6, 06: Scientists have recovered DNA from a Neandertal that lived 100,000 years ago --the oldest human-type DNA so far. Researchers isolated the genetic material from mitochondria. These are "power pack" structures in cells which contain their own DNA. It was extracted from the tooth of a Neandertal child found in the Scladina cave in the Meuse Basin, Belgium.
. . The study suggests our distant cousins were more genetically diverse than once thought. Their diversity had declined, perhaps because of climate change or disease, by the time early humans arrived in Europe about 35,000 years ago.
. . Neandertals lived between 230,000 and 28,000 years ago in Europe, Central Asia and the Middle East. They were skilled hunters and well adapted to living during the ice ages; but they started to die out after modern humans (Cro-Magnons) appeared on the scene in Europe. The reason for their sudden demise is unknown, but various theories have been proposed, including biological, environmental and cultural factors.
. . The DNA studies conducted so far suggest that probably no interbreeding between Neandertals and modern humans took place.

June 5, 06: Wade, in Before the Dawn: Recovering the Lost History of Our Ancestors. Wade shows we may all be descended from as few as 150 humans who abandoned their African homeland. It was a dangerous move, Wade writes, "but by daring so much, they gained the whole world."

June 5, 06: Forget family influence and upbringing. When it comes to being an entrepreneur, genes seem to play an important role, scientists said. A study of identical twins by researchers in Britain and the United States suggests family environment has little influence because nearly half of a person's propensity to be self-employed, or entrepreneurial, is due to genes.
. . By comparing self-employment in 609 pairs of identical twins, who share all the same genes, and 657 pairs of non-identical twins, scientists the impact of genetics and environment on entrepreneurs.
. . The rate of entrepreneurs among twins is the same as in the general population. Spector and his team found that identical twins increased the odds of their twins following the same path more than non-identical twins, which suggests genes are important.
. . Spector is director of the Twin Research Unit at St Thomas' Hospital, which has a registry of 10,000 twins who are studied for a variety of illnesses, personality traits and abilities.

June 3, 06: Electric fish emit weak signals from an organ in their tails that serves as a battery. Different emissions signal aggression, fear or courtship. While the fish can apparently understand each others' warning signals, "They seem to only choose to mate with other fish having the same signature waveform as their own."
. . But in the Ivindo River in Gabon, Arnegard and colleagues have found fish with the same DNA emitting distinctly different signals. The fish are likely on the verge of splitting into two species, the researchers announced today. "We think we are seeing evolution in action."
. . The process of splitting one species into two is called speciation. Scientists figure there are two ways it can happen. Groups can become geographically separated and take on new traits as their genes mutate. Or, animals can stay together but for some reason mate selectively to form distinct groups. The latter method, called sympatric speciation, is seen to be less likely and somewhat controversial.

June 2, 06: From his vantage point atop the highest peak in southern Arizona, Father Jose Funes is lining up the Vatican telescope for a night of observation, probing the processes that lead galaxies to form and stars to be born.
. . Funes, an astronomer and a Jesuit priest, is one of a dozen scientists, most of them Jesuits, associated with the Vatican Observatory Research Group that operate the Arizona telescope and engages in advanced astrophysics, cosmology and galactic and extragalactic research.
. . Few Catholics and even fewer Americans are aware that the Vatican has a telescope in Arizona or even that the Catholic Church engages in scientific research. But the priests see themselves bridging the gap between science and religion.
. . In the process, they have emerged as a powerful voice against "creationism" and the theory of "intelligent design", which holds that certain forms in nature are too complex to have evolved through natural selection and must have been created by a "designer" who might be called God.
. . According to a 2005 Pew Research poll, 42% of Americans believe that "life on Earth has existed in its present form since the beginning of time." Stoeger called the faith of those who believe in the literal account of creation as described in the Book of Genesis as belief based on ignorance. "Their theology is very primitive and they have no adequate means ... to integrate their (religious) tradition with the real world", he said.

June 2, 06: Moles do a lot of digging, as many gardeners know. But they don't use whiskers to find their way around in the dark. Instead, they simply follow their noses.
. . A new detailed study of tiny touch receptors, called "Eimer's organs", on the tip of a mole's nose reveals how the animals do it. For moles, the Eimer's organs serve the function of whiskers found in most small mammals and fingers in humans. By touching their noses to the ground repeatedly, the animals explore their surroundings and discriminate between different objects.
. . The Eimer's organs in the coast mole and the odd-looking star-nosed mole are composed of a column of skin cells, around which numerous nerve endings are arranged. An outer ring of nerves interlacing the column function as high-threshold pain receptors, while nerves within the cell column act as low-threshold touch receptors.
. . The researchers think that this organization allows the outer nerves to sense abrasive or potentially harmful areas before the more sensitive inner nerves come into contact with them.

June 2, 06: An apparent crater as big as Ohio --about 500 km wide-- has been found in Antarctica. Scientists think it was carved by a space rock that caused the greatest mass extinction on Earth, 250 million years ago.
. . The crater, buried beneath a half-mile of ice and discovered by some serious airborne and satellite sleuthing, is more than twice as big as the one involved in the demise of the dinosaurs. The crater's location, in the Wilkes Land region of East Antarctica, south of Australia, suggests it might have instigated the breakup of the so-called Gondwana supercontinent, which pushed Australia northward.
. . It was found by looking at differences in density that show up in gravity measurements taken with NASA's GRACE satellites. Researchers spotted a mass concentration, which they call a mascon—dense stuff that welled up from the mantle, likely in an impact.
. . So Frese and colleagues overlaid data from airborne radar images that showed a 300-mile wide sub-surface, circular ridge. The mascon fit neatly inside the circle. "And when we looked at the ice-probing airborne radar, there it was."
. . The Permian-Triassic extinction, as it is known, wiped out most life on land and in the oceans. Researchers have long suspected a space rock might have been involved. Some scientists had blamed volcanic activity or other culprits. The die-off set up conditions that eventually allowed dinosaurs to rule the planet.
. . The newfound crater is more than twice the size of the Chicxulub crater in the Yucatan peninsula, which marks the impact that may have ultimately killed the dinosaurs 65.51 million years ago. The Chicxulub space rock is thought to have been 10 km wide, while the Wilkes Land meteor could have been up to 50 km wide.

June 1, 06: Researchers at the University of Southern Maine have identified a "starter hormone" responsible for initiating the process by which caterpillars transform themselves into moths. The researchers also discovered that by manipulating hormone treatments, they could arrest a caterpillar's growth, a finding they suggest will lead to a better understanding of how hormones can control growth in humans.
. . One finding was that the cells that formed the moth's eye were actually skin cells in the caterpillar.

June 1, 06: Scientists have finally figured out the exact moment when a jumbled swarm of creatures becomes an organized, unified, and sometimes terrifying, mass.
. . Examining a group of desert locusts, researchers found that at low densities, the insects were unorganized and went their separate ways. But when the group's density increased, the bugs fell into an orderly line and began to follow the same direction. This understanding could help control pests that destroy crops and spread disease.
. . The test placed locusts in an arena and filming them as they joined each other to form a group. When there were a few of them together, they did not coalesce. As the group grew to 10 to 25 members, the locusts got closer to each other, but still did not move in unison. It was only when the researchers placed about 30 locusts in the arena that the insects fell into a line and started moving in the same direction. They had reached their "tipping point."

June 1, 06: The afternoon siesta is not just a cultural tradition in some countries. It's a biological reaction to lunch. Researchers have revealed how the sugar in food, called glucose, "can stop brain cells from producing signals that keep us awake."
. . His team figured out how glucose blocks neurons that make orexins, which are tiny proteins that help us stay conscious. Malfunction of orexin neurons can lead to narcolepsy -—the chronic inability to stay awake—- and obesity.
. . "Now we know how glucose stops orexin neurons 'firing', we have a better understanding of what may occur in disorders of sleep and body weight", Burdakov said. "This may well provide an explanation for after-meal tiredness and why it is difficult to sleep when hungry."

June 1, 06: For male guppies, being unique is good for more than just attracting the ladies -—it could mean the difference between life and death. A new study finds that guppies with rare color patterns are less likely to be gobbled by prowling predators than their commonly colored counterparts. The finding is an example of how nature sometimes favors rare traits. "It's possible that guppy predators, which are known to hunt visually, may be more focused on common color patterns."
. . The finding is an example of what biologist call "negative frequency-dependent selection", in which natural selection favors rare traits over common ones. It's been hypothesized that a similar process could explain why a small percentage of humans are left-handed. According to one idea, left-handed fighters have a surprise advantage over their right-handed adversaries.

June 1, 06: We may not be entirely human, gene experts said on today after studying the DNA of hundreds of different kinds of bacteria in the human gut. Bacteria are so important to key functions such as digestion and the immune system that we may be truly symbiotic organisms --relying on one another for life itself, the scientists write.
. . Their findings suggest that studying bacteria native to our bodies may provide important clues to disease, nutrition, obesity and how well drugs will work in individuals, said the team at The Institute for Genomic Research, commonly known as TIGR.
. . Scientists have long known that at least 50% of human feces, and often more, is made up of bacteria from the gut. Bacteria start to colonize the intestines and colon shortly after birth, and adults carry up to 100 trillion microbes, representing more than 1,000 different species. "This is the densest bacterial ecosystem known in nature."
. . They are not just freeloading. They help humans to digest much of what we eat, including some vitamins, sugars, and fiber. They also synthesize vitamins that people cannot. "Humans have evolved for million of years with these bacteria. And they provide essential functions", Gill said.
. . They compared the gene sequences to those from known bacteria and to the human genome and found this so-called colon microbiome --the entire sum of genetic material from microbes in the lower gut-- includes more than 60,000 genes. That is twice as many as found in the human genome. "Of all the DNA sequences in that material, only 1 to 5% of it was not bacterial", Gill said. "We were surprised."
. . They also found a surprising number of Archaea, also known as archaebacteria, which are genetically distinct from bacteria but which are also one-celled organisms often found in extreme environments such as hot springs.
. . The next study will focus on the bacteria in the mouth, Gill said. There are at least 800 species in the mouth and maybe more.
. . One of the microbes whose genes were analyzed helps determine how much of the calories we absorb from the food we eat. Called Methanobrevibacter smithii, it eats up hydrogen waste products released by other microbes in our gut and converts it into methane gas.
. . Mice that have large concentrations of M. smithii in their guts are fatter than those that don't have the bacteria. The finding, which Samuel presented at a recent meeting of the American Society for Microbiology, presents the intriguing possibility that scientists could plant different microbes in our guts to help us gain or lose weight.

May 31, 06: Hobbit-sized humans who survived on an isolated Indonesian island until 12,000 years ago were smart enough to make stone tools even though they had small brains, scientists said today.
. . Some researchers doubt that tools found with the remains of the species named Homo floresiensis in a cave on the island of Flores could have been made by the 1 meter tall creatures whose brains were about the size of a grapefruit.
. . An international team of scientists said older tools dating back more than 800,000 years also found on the island showed the 'hobbits' probably inherited their tool-making skills from their ancestors. "Small-brained or not, Homo floresiensis was capable of making stone tools and therefore the standard story of the relationship between brain size and behavioral complexity in human evolution may be less straightforward than currently assumed", said Adam Brumm, of the Australian National University in Canberra, who headed the team.
. . Until now, it was thought that the larger the brain, the smarter the hominid. Brumm said his findings suggest that may not be the case. "The causal relationship between brain size and the complexity of tool behavior in humans is assumed, not demonstrated", said Brumm. "Until now, stone tools have only been found in association with large and relatively large-brained hominids, but Homo floresiensis changes that, forcing us to re-think the way we associate big brain with sophisticated behavior."
. . The researchers said their findings show the same types of stone tools found with the species were made by their ancestors when they arrived on the island at least 840,000 years ago.

May 30, 06: RAIDING parties, subterfuge and warfare. Chimps use these tactics, humans are all too skilled in them, and now they have been observed for the first time in a non-ape --the relatively little-known spider monkey.
. . During a long-term study of the monkeys in Mexico, Filippo Aureli of Liverpool John Moores University, UK, and his colleagues came upon small groups of males travelling deep into the territory of neighbouring monkeys. Spider monkeys (Ateles geoffroyi) usually spend all their time in the trees, so the researchers were amazed to see these males creeping along silently in single file on the ground, looking about them and rarely stopping to feed.
. . "They were clearly aware that they were on risky territory and behaved in exactly the way described for groups of male chimpanzees when searching for members of neighbouring communities to attack", says Aureli. Four of the seven witnessed raids resulted in concerted aggression.

May 30, 06: The appendix serves no purpose ... right? Wrong. Although most biology textbooks say the appendix is useless, we shouldn't sell the organ short.
. . Biologists in the early 20th century surmised that the human body had over 100 useless parts left over from our more ape-like lifestyle a few million years ago. The parathyroid was one such organ, now known to regulate calcium-phosphorous metabolism. The appendix was another.
. . The appendix is a slimy, dead-end sac that hangs between the small and large intestines. It's about a half inch in diameter and three inches long. As quickly as 11 weeks after conception, the appendix starts making endocrine cells for the developing fetus. Endocrine cells secrete useful chemicals, such as hormones, and the appendix endocrine cells secrete amines and peptide hormones that help with biological checks and balances as the fetus grows.
. . After birth, the appendix mainly helps the body stave off disease by serving as a lymphoid organ. Lymphoid organs, with their lymphoid tissue, make white blood cells and antibodies.
. . The appendix, by virtue of its lymphoid tissue, is part of a complicated chain that makes B lymphocytes (one variety of white blood cell) and a class of antibodies known as immunoglobulin A antibodies. The appendix also produces certain chemicals that help direct the white blood cells to the parts of the body where they are needed the most.
. . The dirty gut is a good training ground for young white blood cells. The appendix, with its sac routinely collecting and expelling foodstuffs, exposes the white blood cells to myriad bacteria, viruses and drugs passing through the gastrointestinal tract. This way, the white blood cells learn to fight potentially deadly bacteria, such as E.coli.
. . The appendix's contribution to the body's white blood cell and antibody production reaches its peak when you are about 20 or 30 years old, then production falls off sharply. By age 60, the appendix serves very little active purpose.

May 27, 06: When Escherichia coli bacteria sit down at the dinner table, they often feast on the DNA of their dead competitors, a new study reports.
. . The E. coli bacteria live in the guts of warm-blooded animals, where they aid digestion. Some strains produce toxins that can kill people, however. They become dangerous when picked up from contaminated food.
. . The bacteria are hardy creatures. And those that can manage to live a little longer than their peers not only end up having less competition for food, but also can eat their long lost friends. "The bacteria actually eat the DNA, and not only that, they can use the DNA as their sole source of nutrition", said Steven Finkel, assistant professor of molecular and computational biology at the University of Southern California.
. . It makes sense that DNA is a food source for some microbes, the researchers say. "You're surrounded by living things, and living things die", Finkel said. "Where does all that stuff go? Why aren't we up to our ears in DNA, in ribosomes, in plant protein?"

The study found eight genes in E. coli that allow it to consume DNA without causing any genetic harm to the bacteria.

May 24, 06: So little light makes it to the deep, dark waters where sperm whales do their hunting that they're essentially blind as bats. Like bats, they can use echolocation to find their prey, according to new research.
. . Researchers used suction cups to attach acoustic recording tags to their backs --used to both track the whales and record the sounds they emitted while foraging. As the whales began their dive from the surface, they emitted a regular series of "clicks." When they reached the bottom of the dive, the clicks were emitted more often, eventually combining to form a "buzz" sound.
. . When the pattern of spaced out clicks turning to a continuous buzz, the researchers said, the whale is homing in on the location of its meal. As the creature closes in on the squid, it switches to this buzz, which bounces more sound waves off the squid, providing the whale with more precise information on where the prey is.

May 24, 06: Mice in a lab experiment inherited the effects of an aberrant gene without inheriting the gene itself, a bizarre-sounding result that may someday help scientists understand aspects of diabetes, infertility and other problems.
. . While DNA is the stuff of genes in mice and men, the study indicates that DNA's chemical cousin, RNA, produced the result. In this case, the result was mice with distinctive white coloring on the tip of their tails. Under the rules of classical genetics, one would expect that mice that ended up with two normal copies of the gene would show normal coloring. But surprisingly, 24 out of 27 mice with two normal copies still showed the telltale white patches associated with the aberrant copy.
. . When scientists bred their special mice to others that had only normal copies of the gene, most offspring with only normal gene copies still showed the distinctive coloring. Experiments showed the trait could be inherited through either the mother or father, and it went on for generations in absence of the abnormal gene.
. . RNA normally delivers instructions from genes to a cell's protein-making machinery, so it makes sense that it might be involved in transmitting a gene's effect.
. . Soloway said it's not clear how common or important this kind of inheritance is, but he noted that a similar pattern of effects appeared in a 1997 analysis of a human gene that predisposes people to Type 1 diabetes.

May 24, 06: Tiny Caribbean spiny lobsters are social creatures that live together in underwater caves. But scientists have shown that the creatures can sense a lethal virus in other lobsters, even before they show signs of sickness, and then avoid them. "This is the first record of healthy animals avoiding diseased members of their own species in the wild." They suspect the lobsters' acute sense of smell gives them advanced warning of illness.
. . When young healthy lobsters were confined in labs with sick creatures, more than 60% become ill within 80 days but the infection rate in wild populations in Florida is only 7%.
. . Shields and his team said the lobsters' behavior helped to curb the spread of the virus in the wild. They believe the ability to detect and avoid sick neighbors before they show symptoms of the illness gives them an evolutionary advantage which they can pass on to their offspring.

May 23, 06: Your nose is one powerful protrusion. Whether it's a big honker or a little button, if it is working correctly you can sense a skunk from only 0.000,000,000,000,071 of an ounce of offensive spray. Animals can trace even tinier trails. Male luna moths, for example, track females from 8 km away.
. . Take a deep breath. Air is sucked up into your nostrils over bony ridges called turbinates, which add more surface area to your sniffer. The air travels over millions of olfactory receptor neurons that sit on a stamp-size sheet, the olfactory epithelium, on the roof of the nasal cavity. Odor molecules in the air stimulate and inhibit the receptors.
. . Each aroma sets off a signal made by the receptors that travels along the olfactory nerve to the olfactory bulb. The olfactory bulb sits underneath the front of your brain. Signals from the bulb tell your brain what reeks. Humans can recognize 10,000 different odors. However, no two people sense anything the same.
. . * When we're hungry, our smell sense grows stronger.
. . * Women have keener whiffers than men and like the smell of a symmetrical man best.
. . * At certain times of the month, men say the scent of a woman is more attractive.
. . * Our schnozzes are at their worst in the mornings, improving as the day goes on.
It can affect taste buds too. Researchers say 80% of the flavors we taste come from what we smell, which is why foods become relatively flavorless when we're plugged up.

May 19, 06: Working with evolution, fussy female fish have caused desperate males to blush bright red or take on a victorious blue-ribbon shade of indigo.
. . Two species of cichlid fish swimming in East Africa's tropical Lake Victoria are brilliantly hued because females chose the brightest male partners, according to new research. Although the females of both species resemble each other, with drab gray-brown coloring, the males look completely different.
. . The males of one species, Pundamilia pundamilia, are metallic blue. They eat insect larvae in the shallows. The Pundamilia nyererei males are bright red and yellow. They feed on zooplankton and spend most of their time in deeper water.
. . Habitat depth and color have become linked. Blue light is absorbed by water, and only the red makes it effectively to deep water. So the fish's eyes have adjusted by species. The blue variety in shallow water see blue better, while the red ones in deeper water are more sensitive to red. "At the same time, females in this population developed a preference for brightly colored, conspicuous males."
. . We think that as a result of this, eventually only the bright red and bright blue fish remained, and two separate species would arise. Now that the two species do not interbreed anymore, the differences between them may increase and new differences may accumulate."
. . Colors do more than boost a male's sex appeal. It turns out vibrant males are the healthy choice. Maan discovered the brightest males of both species carry fewer parasites. Similar pickiness has been found at work in other species, and even people use beauty cues to pick healthy, promising partners.
. . When light is dim, females stop picking the bright males and choose the biggest ones instead, because size is an easier feature to pinpoint than color.

May 19, 06: Scientists found fossilized depressions and footprints in Alaska's Denali National Park and Preserve in what is believed to be the first evidence of prehistoric wading birds probing for food, a geologist said. The tracks and the feeding marks found in rocks formed from freshwater sediments were 65.51 million to 70 million years old. Such evidence of prehistoric birds' feeding behavior is difficult to find because the marks made in the mud disappear easily and the fossilized evidence often erodes.

May 19, 06: A single genetic mutation is all it takes to transform selfish bacteria into altruistic team players that contribute resources to the entire group, even when they themselves might not survive to benefit, a new study shows. One result can be a "superstrain" of survivors.
. . The finding demonstrates how simple genetic changes can lead to relatively complex forms of cooperation. When food becomes scarce, social bacteria Myxococcus xanthus clump together into hardy spores that can withstand environmental stresses for long periods of time. A spore is a cocoon of sorts that serves as a seed for future generations.
. . Each spore of M. xanthus contains about 100,000 starving cells that pool their meager resources. Many cells die during the process and never become part of the spore.
. . Some mutated strains of M. xanthus can't form spores on their own but are more efficient than their non-mutated peers at doing so when the two strains are mixed. These so-called cheater strains take over an entire population by out-competing normal strains for the limited spots in the spores. However, by doing so, the mutant bacteria ensure their own destruction because they require normal cooperative strains to kick start the process of making a spore.
. . Indeed, in most of the experiments in which cheating and social bacteria were mixed, the entire population died out. But in one special case, the merged population led to the creation of a new superstrain of cooperative bacteria that produced more surviving cells than either of the two original strains.
. . When the researchers sequenced the superstrain's genome, they discovered that its newfound success was due to a single mutation in the DNA of the cheater bacteria.

May 19, 06: French scientists who explored the Coral Sea said they discovered a new species of crustacean that was thought to have become extinct 60 million years ago. The "living fossil", a female baptized Neoglyphea Neocaledonica, was discovered 1,312 feet under water. The nearly 5-inch creature as "halfway between a shrimp and a mud lobster." Its huge eyes, reddish spots and thickset body distinguished it from a 1908 crustacean. That so-called living fossil from the Neoglyphea group was discovered in 1908 in the Philippines by the U.S. Albatross, a research vessel. It remained unidentified until 1975.

May 18, 06: Apes that remember to carry the right tools to retrieve treats and scrub jays that hide food a second time when they think a rival is watching prove animals can think ahead --a trait once believed to be uniquely human, scientists have found.
. . Two carefully planned sets of experiments (in the journal Science) show intelligent birds and great apes can plan into the future in way that transcends simple food caching, as squirrels, foxes and other animals do. "Apes and jays can also anticipate future needs by remembering past events, contradicting the notion that such cognitive behavior only emerged in hominids."
. . In one experiment, Nicholas Mulcahy and Josep Call of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, tested bonobos, close relatives of chimpanzees, and orangutans at the local zoo. They set up several experiments that required the apes to remember a complex way to retrieve a treat and offered them the opportunity to use tools to do so. To pass the tests, the apes had to remember to bring the right tool out of the room with them, and bring it back with them some time later. Both orangutans and bonobos passed the tests several times.
. . If a bird dominant to the jays saw them store their food, the jays would move the cache later when the dominant bird was not watching. But if the bird allowed to watch the treat being hidden was subordinate, or a mate, the jays did not later re-cache their food --presumably because they could fight off subordinates that try to steal their food, the researchers wrote. Jays are members of a group of birds called corvids, which include crows, jays and ravens and which biologists consider to be the most intelligent species of bird.

May 18, 06: A 70 million year old dinosaur claw fossil found in Brazil reinforces the theory of an evolutionary link between dinosaurs and birds, a new study says. Brazilian scientists dubbed the dinosaur the dino-bird, which they said was found in Minas Gerais state, about 560km northwest of Rio. "The anatomic structure of this claw shows, quite possibly, the link between carnivore dinosaurs and birds that exist today."

May 17, 06: Humans and chimps diverged from a single ancestral population through a complex process that took 4 million years, according to a new study comparing DNA from the two species.
. . By analyzing about 800 times more DNA than previous studies of the human-chimp split, researchers from the Broad Institute of MIT and Harvard were able to learn not just *when, but a little bit about *how the sister species arose.
. . The researchers hypothesize that an ancestral ape species split into two isolated populations about 10 million years ago, then got back together after a few thousand millennia [1000 Millennia = 1 million years]. At that time, the two groups, though somewhat genetically different, would have mated to form a third, hybrid population. That population could have interbred with one or both of its parent populations. Then, at some point after 6.3 million years ago, two distinct lines arose.
. . For one thing, the new data suggest the human-chimp split was much closer to the present than the 7 million year date that fossils and previous studies indicate --certainly no earlier than 6.3 million years ago, and more likely in the neighborhood of 5.4 million.
. . The data also show that the human-chimp split probably took millions of years. That's because in some parts of the DNA sequence the genetic difference between humans and chimps is so large that those genes must have been isolated from each other nearly 10 million years ago. But in other places, the human and chimp lines are so close that they appear to have still been swapping genetic material at least until 6.3 million years ago.
. . One of those areas is the X-chromosome, which is intriguing. "The genes that are a barrier to speciation tend to be on the X-chromosome", said David Reich, the main author of the study.

Based on an estimated relative mutation rate, they calculated how long it would take to accrue the mutations and determined that the first speciation took place around 6.3 million years ago. From start to finish, complete speciation spanned a much longer time range than in any other modern apes.
. . Mixing and matching genetic information from two species doesn't always work out well, and hybrid species often have trouble reproducing. The problem generally arises from differences on the X chromosomes. "In a situation where it's unfavorable to have one X from one species and one from the other, which happens as hybrids reproduce among themselves, you get powerful selection for the good combination", Patterson said. "The X chromosome will fix out and everyone will have the same X."
. . Scientists can't say how long the hybridization carried on, but the final speciation occurred around 5.3 million years ago, possibly because the two species' genetic coded were too different to mix or the animals were simply physically unappealing to each other.
. . Researchers at the Broad Institute are currently working on sequencing gorilla and other primate genomes and searching for similar patterns of evolution to help better tell the whole story.

May 17, 06: It could be mistaken for meaningless jabbering or sound effects from an action comic strip but the "pyow hack hack pyow hack hack" noises of some African monkeys are a signal it is time to leave. All animals make distinct sounds, but male tree-dwelling, putty-nosed monkeys in Nigeria can combine two noises in novel ways to convey new meaning --a trait that was thought to be uniquely human.
. . Dominant putty-nosed male monkeys release the "pyow" sound when leopards are around and the "hack" to warn of approaching eagles. He added that songbirds are known to combine sounds in structure sequences but it has not been linked to meaning or a command to others.

May 17, 06: Scientists have reached a landmark point in one of the world's most important scientific projects by sequencing the last chromosome in the Human Genome, the so-called "book of life."
. . Chromosome 1 contains nearly twice as many genes as the average chromosome and makes up 8% of the human genetic code. It is packed with 3,141 genes and linked to 350 illnesses including cancer, Alzheimer's and Parkinson's disease. Researchers around the world will be able to mine the data to improve diagnostics and treatments for cancers, autism, mental disorders and other illnesses. The genetic map of chromosome 1 has already been used to identify a gene for a common form of cleft lip and palate. It will also improve understanding of what processes lead to genetic diversity in populations.
. . The human genome has an estimated 20,000 to 25,000 genes. The sequencing of chromosome 1 has led to the identification of more than 1,000 new genes.
. . The scientists also identified 4,500 new SNPs --single nucleotide polymorphisms-- which are the variations in human DNA that make people unique. SNPs contain clues about why some people are susceptible to diseases like cancer or malaria, the best way to diagnose and treat them and how they will respond to drugs.

May 16, 06: The first sequences of nuclear DNA to be taken from a Neandertal have been reported at a US science meeting. Geneticist Svante Paabo and his team say they isolated the long segments of genetic material from a 45,000-year-old Neandertal fossil from Croatia. The work should reveal how closely related the Neandertal species was to modern humans, Homo sapiens. It is a significant advance on previous research that has extracted mitochondrial DNA.
. . So far, Paabo and colleagues have managed to sequence around a million base-pairs, which comprises 0.03% of the Neandertal's entire DNA "catalog", or genome. Base-pairs are the simplest bonded chemical units which hold together the DNA double helix.
. . Preliminary analysis shows the bundle of DNA responsible for maleness in the Neandertal --its Y chromosome-- is very different from modern human and chimpanzee Y chromosomes; more so than for the other chromosomes in the genome. This might suggest that little interbreeding occurred between our own species and the Neandertals.
. . The base-pairs show that Neandertals diverged from the evolutionary line that led to modern humans about 315,000 years ago. Neandertals lived across Europe and parts of west and central Asia from approximately 230,000 to 29,000 years ago.

May 11, 06: A species of monkey discovered in the highland forests of Tanzania last year is so unusual that it's been assigned its own genus, scientists said. This marks the first time in 83 years that a new monkey genus has been found. In taxonomy, a genus ranks below a family and above a species. Researchers now say the monkey --known as kipunji-- is more closely related to some types of baboon than to mangabeys, though it is anatomically different from baboons.
. . Even as scientists are just learning about the new creature, its high-altitude forest home is already being threatened by illegal logging and hunting. With only about 500 Kipunji monkeys left in the wild, the animals will probably be classified as "critically endangered", the researchers write, and quick action is required if they are to survive.

IQALUIT, Nunavut - an Inuvialuit guide from the North West Territories was the first to suspect it had actually happened when he proposed that a strange-looking bear shot last month by an American sports hunter might be half polar bear, half grizzly.
. . Territorial officials seized the creature after noticing its white fur was scattered with brown patches and that it had the long claws and humped back of a grizzly. Now a DNA test has confirmed that it is indeed a hybrid — possibly the first documented in the wild. It's a... Pizzly.

May 9, 06: Bottlenose dolphins can call each other by name when they whistle, making them the only animals besides humans known to recognize such identity information, scientists reported.
. . Scientists have long known that dolphins' whistling calls include repeated information thought to be their names, but a new study indicates dolphins recognize these names even when voice cues are removed from the sound. For example, a dolphin might be expected to recognize its name if called by its mother, but the new study found most dolphins recognized names --their signature whistles-- even when emitted without inflection or other vocal cues. More than that, two dolphins may refer to a third by the third animal's name.
. . She stopped short of saying dolphins might have a human-like language. "I tend to shy away from using the word 'language' myself, because it's such a loaded term", Sayigh said. "I still really feel strongly that there is no evidence for something like our language. (Dolphins) have got the cognitive skills at least to have referential signals."

May 9, 06: It hasn't always been an ant's world. Scientists estimate modern-day ants first evolved about 120 million years ago. But the fossil record suggests that ants at this time weren't the prevalent insect that they are today. Not until 60 million years later, when some ants adapted to the new world of flowering plants and diversified their diets, did the critters achieve ecological dominance. Since then, they've had a successful run of the planet.
. . Scientists estimate that about 20,000 ant species crawl the Earth. Taxonomists have classified more than 11,000 species, which account for at least one-third of all insect biomass. The combined heft of ants in the Brazilian Amazon is about four times greater than the combined mass of all of the mammals, birds, reptiles, and amphibians, according to one survey.
. . Even their appearance and where they live contrasts from one ant to the next. They can be as tiny as the millimeter-long Oligomyrmex atomus or as big as the aptly named 1.5 inch-long Dinoponera. They come in a range of colors from yellow and red to black. They exist in deserts, rain forests, and swamps -—anywhere but the coldest and highest places on Earth.
. . Some species of carpenter ants construct defensive shelters around the base of plants, to guard against other insects and protect their food supply. Trap-jaw ants, Odontomachus, snap shut their predatory jaws so quickly you can hear it click.

May 8, 06: The number of years that modern humans are thought to have overlapped with Neandertals in Europe is shrinking fast, and some scientists now say that figure could drop to zero.
. . Neandertals lived in Europe and western Asia from 230,000 to 29,000 years ago, petering out soon after the arrival of modern humans from Africa. There is much debate on exactly how Neandertals went extinct. Theories include climate change and inferior tools compared to those made by modern humans.
. . The overlap figure shrank in February with new research by Paul Mellars of Cambridge University based on improved carbon-14 dating to show that modern humans started encroaching from Israel upon Neandertal territory in the Balkans 3,000 years sooner than previously thought. This rate suggests Neandertals succumbed sooner to big climate shifts or competition from modern humans for resources and that they might have overlapped for only 1,000 years at sites in western France.
. . Try zero years, says anthropologist John Hawks of the University of Wisconsin -Madison. There is no longer any biological evidence of overlap between Neandertals and non-Neandertals in Europe, Hawks wrote recently in his blog.
. . For one key culture, though, called the early Aurignacian, there are no fossils, just sophisticated jewelry and stone and bone tools that many claim could only be made by modern humans with their advanced technologies relative to Neandertals.
. . A number of scientists recently have agreed that the carbon-14 dates on numerous fossils of modern humans should be shifted 2,000 to 7,000 years earlier. The recent Mellars research is one example of this work.
. . The trouble is that this trend leaves "a great big hole" in the fossil record when it comes to the early Aurignacian, Hawks said. The only group in Europe at the right time and place to have made the jewelry and tools attributed to early Aurignacian culture is the Neandertals, he said. So even if Neandertals failed to outlast modern humans, we might have to give them more credit for their handiness with tools.

May 5, 06: In a rare type of discovery, researchers have identified a whole new genus of cricket in caves in Grand Canyon-Parashant National Monument in northwestern Arizona. A genus is a major subdivision within a family of living things that typically includes more than one species.
. . Of more than 1,000 known caves in Arizona, only 3% have been significantly surveyed by biologists. "Cave ecosystems are one of the most poorly understood and fragile ecosystems. Because caves are extreme environments, cave arthropods are very specialized and possibly endemic to a single cave system or region. They present interesting and odd evolutionary forms that reflect the extreme environments found in caves."

May 4, 06: Take it from bees. Intense competition is better than touchy-feely "win-win" negotiations when it comes to making big decisions.
. . Ten years of painstaking research on how swarms of honeybees choose a new hive now shows their voting process for selecting new real estate is efficient and yields some losers while avoiding the folly of the collective, or of trying to come to a consensus. The bees' approach might sound hardcore and less than democratic. But it almost always results in the choice of the best home among available options, said Thomas Seeley of Cornell University.
. . If humans were to take a page from honeybee home hunting, we too could learn to minimize bad decisions, he said. "How the scout bees select candidate sites, deliberate among choices and reach a verdict is a process complicated enough to rival the dealings of any corporate committee."
. . Here is what they found: When bees outgrow their hives, a few hundred scouts selected by the queen search for the perfect, new location for a swarm—a south-facing knothole that is smaller than 4.7 square inches, perched several yards above the ground and leads to a hollow in the tree that is at least 20 liters in volume.
. . Scouts return to the waiting swarm and perform a waggle dance, vibrating their abdomens laterally while walking in figure eights, to report on what they found. The longer the waggle dance, the better the site. This prompts other scouts to visit the recommended site.
. . Scouts compete to attract uncommitted scouts to visit their sites. As time passes, coalitions form that prefer one site over another. Instead of hashing it out endlessly, the group usually makes a decision with no more than 16 hours of dancing debate. As soon as 15 or more bees are at any one site, the scouts signal to the waiting bees in the swarm to warm up their flight muscles. Soon, the swarm lifts off toward its new home.
. . "The bees' method, which is a product of disagreement and contest rather than consensus or compromise, consistently yields excellent collective decisions."

May 4, 06: Scientists have found about 10-20 new species of tiny creatures in the depths of the Atlantic in a survey that will gauge whether global warming may harm life in the oceans, an international report said. The survey, of tropical waters between the eastern United States and the mid-Atlantic ridge, used special nets to catch fragile zooplankton --animals such as shrimp, jellyfish and swimming worms-- at lightless depths of 1-5 km.
. . Most life, including commercial fish stocks, is in the top 1 km of water, but the scientists said the survey showed a surprising abundance even in the depths. The survey will provide a benchmark to judge future changes to the oceans.
. . Zooplankton are a key to transporting carbon dioxide to the depths because they can swim 500 meters up and down daily. Many species eat their own weight every day in plant phytoplankton species near the surface. 10,000 kg of phytoplankton is consumed by 1,000 kg of zooplankton, which in turn support 100 kg of larger zooplankton, which become meals for 10 kg of small fish species like herring or anchovies, which support 1 pound of a larger fish species that might end up on your dinner table.
. . The expedition has provided a new understanding of the diversity of gelatinous zooplankton, which the researchers describe as "the gooiest, stickiest, and most transparently fragile animals of the sea." They are rarely captured without being destroyed.

May 4, 06: Scientists have discovered a 405-million-year-old fossilized fish that shares characteristics of modern bony fishes and land vertebrates. Hundreds of millions of years ago, bony sea creatures of the group Osteichtheyes hit an evolutionary fork in the road. Some animals took the path towards Actinopterygii, a group of modern, ray-finned fish. The rest evolved into Sacropterygii, the group that includes the ancestors of land vertebrates—coelacanths, lungfishes, and tetrapods.
. . Scientists pieced together the new fish species, Meemannia eos, from four incomplete skulls unearthed in China.

May 3, 06: The biologist in Randy Olson cringed at news reports of evangelical Christians challenging the teaching of evolution to schoolchildren in places such as Kansas on the grounds it was "just a theory". But the filmmaker in him feels just as strongly that scientists have done a lousy job explaining their side of the debate.
. . The result is "Flock of Dodos: The Evolution-Intelligent Design Circus", a humorous and entertaining documentary that premiered at New York's Tribeca Film Festival this week.
. . Olson gives the intelligent design advocates plenty of airtime but the film exposes what Olson sees as the fallacies of best-selling authors who provide the intellectual firepower of the intelligent design movement. He balances his critique of academics --too rigid and arrogant-- with a calm, orderly attack on the arguments backing intelligent design.

May 1, 06: Plants and animals living in warm, tropical climates evolve faster than those living in more temperate zones, a new study suggests. The finding could help explain why rainforests have such rich biodiversity compared to other parts of the planet.
. . A census of all the plants and animals around the world would reveal that species richness is uneven: it is highest in the tropics, the regions of Earth near the equator, and lower the closer one goes toward the planet's poles.
. . Like characters in a four-letter alphabet, bases are DNA molecules arranged to spell out instructions for building proteins. If one of the letters—A, T, G or C—become substituted with another, the instructions can change and a dysfunctional or entirely new and useful protein can be produced. The researchers found that tropical plants had more than twice the rate of base substitution compared to their temperate cousins.
. . Scientists think it works like this: Warmer temperatures speed up metabolism by allowing chemical reactions to occur at a faster rate, but this increased efficiency comes at a price: it produces higher quantities of charged atoms or molecules called "free radicals," which can damage proteins—including DNA. Higher metabolism also speeds up DNA replication, which is just another chemical reaction, and this can increase the number of copying mistakes that can occur.
. . Together, damage to DNA by free radicals and replication mistakes could result in mutations that, over time and through natural selection pressures, can form new species.

Apr 26, 06: When a mother does her best, she expects a well-behaved child. But for top-dog hyena moms, a hell-raiser is preferred. [Hyenas are not related to dogs. African Wild Dogs are, but just barely....] Alpha females give a hormone boost to their developing cubs, making them more aggressive when fighting for food and increasing their chances of survival. The extra hormones also inspire young males to mount females early and often, giving them a better shot at performing their tricky mating dance correctly down the road.
. . Unlike most mammalian societies, female spotted hyenas run the show and are significantly more muscular and aggressive than males. After studying hyenas in Kenya for nearly two decades, researchers discovered that in the final stages of pregnancy, high-ranking females provide their developing offspring with higher levels of androgen—a male sex hormone associated with aggression—than lower-ranking mothers provide to their developing young.
. . This is the first study to show that a mother's social status, and not just her genetic makeup, can directly affect her offspring's observable physical characteristics.
. . Aggressiveness is a good attribute for a creature living in a society where 40 to 60 individuals scrap over food, and especially for females requiring extra energy for developing offspring. But providing the extra hormones takes a toll on the mother. The dose of androgen that she received from her own alpha mother damages her ovaries, making it difficult to conceive.
. . It also causes female reproductive organs to grow. A lot. Her clitoris, which contains the birthing canal, protrudes 7 inches from her body. "Imagine giving birth through a penis",said study co-author Kay Holekamp of Michigan State University. "It's really weird genitalia, but it seems to work. Although giving birth through a 'penis' isn't a trivial problem." The clitoris' birth canal is only an inch in diameter, and the tissue often tears as a 2-pound cub squeezes through the narrow opening. The rip can be fatal, as evidenced by the high death rate for first-time mothers.
. . Because of the female's awkward genitalia, successful mating for hyenas is tricky to pull off. It takes careful positioning for the male to crouch behind her and somehow get his penis to point up and backwards to enter her clitoris.
. . Since the sons of alpha females are born hyper-aggressive, they start trying to mount females at just a few months old, giving them a better shot at sealing the deal later in life.

Apr 26, 06: Noam Chomsky has endured many attempts to disprove his widely respected theories of language, but never have any of them come from a 3-ounce bird.
. . The European starling, a tiny virtuoso, has the ability to learn and recognize a feature of grammar that has long been thought to be unique to human languages, researchers report in a new study. European starlings are not just exceptional songbirds and mimics they also recognize a grammar in their songs. Scientists in the US have discovered that the birds can be taught to identify different patterns of organizing sounds used to communicate.
. . Chomsky isn't buying it, however.
. . A common characteristic of human grammar is inserting words and clauses within a sentence, without limit. For example, "Oedipus ruled Thebes" can become "Oedipus, who killed his father, ruled Thebes" or "Oedipus, who killed his father, whom he met on the road from Delphi, ruled Thebes", ad infinitum. More simply stated, you can insert as many brackets as you want within a sentence as long as there are as many brackets on the right as there are on the left. While humans change a sentence by inserting words, starlings combine chirps, warbles, trills, whistles and rattling sounds.
. . Chomskian linguists believe that this characteristic, known as recursive center embedding, is a universal feature of human language, and the ability to process it forms the core of human language ability.

Apr 25, 06: A mathematical analysis of the human genome suggests that so-called "junk DNA" might not be so useless after all.
. . The term junk DNA refers to those portions of the genome which appear to have no specific purpose. But a team from IBM has identified patterns, or "motifs", that were found both in the junk areas of the genome and those which coded for proteins. The presence of the motifs in junk DNA suggests these portions of the genome have an important functional role.
. . They used a mathematical tool known as pattern discovery to tease out patterns in the genome. This technique is often used to mine useful information from very large repositories of data in the worlds of business and science.
. . The researchers found millions of the motifs in non-coding DNA. But roughly 128,000 of these also occurred in the coding region of the genome. These were also over-represented in genes which are involved in specific biological processes. These processes include the regulation of transcription --the beginning of the process that ultimately leads to the translation of the genetic code into a peptide or protein-- and communication between cells.
. . Dr Rigoutsos said his team's work suggested "a connection between a vast area of the genome we didn't think was functional with the part of the genome we knew was functional".
. . "A human embryo starts out as a single fertilized cell and rapidly divides into a widely complex series of cells that become a human being", explained Dr McCallion. "Every cell in that human being contains the same complement of genes and what makes each cell different is the precise way that genes are turned on and turned off."

Apr 25, 06: To claim the country's first dinosaur discovery, Norwegians had to dig more than 2Km down. An oil drilling operation uncovered the knucklebone of a Plateosaurus. Well, actually, the knucklebone is now crushed. And it's not actually in Norway proper, but below the North Sea. Whatever the case, it's a neat piece of record-setting, accidental paleontology.
. . The fossil is the deepest dinosaur remain ever found. The knucklebone was found in a hollow grave within sediment 2,256 meters below the seabed. The area was once dry plains with rivers running through them. Researchers said it's quite possible there are many more fossils down there.

Apr 23, 06: If you want to sneak up on an animal, you might want to wheel up on a bicycle rather than try the tip-toe technique. They looked at how humans detect and interpret movement to hint at how animals do it. It seems humans, and likely other animals, are trained to interpret foot movement in a certain way. "We believe this visual filter is used to signal the presence of animals that are propelled by the motion of their feet and the force of gravity."
. . Scientists think this locomotion detector is part of an evolutionarily old system that helps animals quickly detect whether a potential predator or prey is nearby, even if it's just in their peripheral vision. Other research suggests that even newly hatched chicks use this "life detector" system. "It seems like their brains are 'hard wired' for this type of recognition." Some hunting animals, such as cats, creep along to disguise the foot component of their movement, allowing them to sneak up on prey more easily.
. . The study might also provide an explanation for phobias towards snakes, insects, spiders, and birds -—animals that don't fit the "normal" movement patterns associated with the proposed life detector, Troje said.

Apr 19, 06: Imagine while walking to the grocery, every few streets you have to go back home to reset your navigation system in order to avoid getting lost.
. . That's what ants have to do. Now and then they must visit their nest to avoid losing their way on foraging trips. Now scientists are using this understanding to make better robots.
. . Ants use landmarks to find their way, and they also have a backup system called a "path integrator". Measuring the distance traveled and using an internal compass, the system continually reassesses the ant's position. This helps it find straight shots back home even if the outbound trip traversed is a maze.

Apr 19, 06: When studying animals, biologists need a common language, a taxonomy. But with amphibians, the tree of life hadn't been updated since the 1930s. Biologist Darrel Frost of the American Museum of Natural History and colleagues have finally tackled the task. A new image gallery tells the story of the project and highlights some of the colorful and slithering species involved.
. . The researchers say the work has radically revised understanding of amphibian evolution. "The new amphibian tree of life shows that the taxonomy up to this point has been hopelessly flawed and provides us with a new taxonomy that offers the scientific community a new starting place from which to address questions about amphibian biodiversity."
. . The new tree was based on DNA and other data from 522 amphibian species, with equal samples of frogs, snake-like caecilians, and salamanders and newts.

Apr 19, 06: A new fossil discovery has revealed the most primitive snake known, a crawling creature with two legs, and it provides new evidence that snakes evolved on land rather than in the sea. Snakes are thought to have evolved from four-legged lizards, losing their legs over time. But scientists have long debated whether those ancestral lizards were land-based or marine creatures.
. . The new find reveals a snake that lived in the Patagonia region of Argentina some 90 million years ago. Its size is unknown, but it wasn't more than a meter long.
. . It's the first time scientists have found a snake with a sacrum, a bony feature supporting the pelvis, he said. [snakes got hips!] That feature was lost as snakes evolved from lizards, and since this is the only known snake that hasn't lost it, it must be the most primitive known, he said.
. . The creature clearly lived on land, both because its anatomy suggests it lived in burrows and because the deposits in which the fossils were found came from a terrestrial environment, he said.
. . If snakes did evolve on land rather than the sea, their fossil record might be less complete because early fossils would have been better preserved in a marine environment, he said. That, in turn, suggests "we may not know all the lineages of early snake evolution", he said. Maybe several snake lineages lost the legs of their lizard ancestors independently.

Apr 18, 06: Scientists are learning more about what appears to be one of the biggest meat-eating dinosaurs known, a two-legged beast whose bones were found several years ago in the fossil-rich Patagonia region of Argentina. One expert called the discovery the first substantial evidence of group living by large meat-eaters other than tyrannosaurs like T. rex. The creature, which apparently measured more than 13 meters long, is called Mapusaurus roseae.
. . The discovery of Mapusaurus included bones from at least seven to nine of the beasts, suggesting the previously unknown animal may have lived and hunted in groups. That hunting strategy might have allowed it to attack even bigger beasts, huge plant-eating dinosaurs.
. . The dig showed evidence of social behavior in Mapusaurus. The excavation found hundreds of bones from several Mapusaurus individuals but none from any other creature. That suggests the animals were together before they died.

Apr 17, 06: New research reveals that octopus stiffen their arms to form human-like joints to guide food to their mouths.
. . A three-jointed human arm has only seven degrees of freedom (DOFs), which are defined as the types of movements each joint can perform. Your shoulder and wrist each have three DOFs—each can tilt up and down, turn left and right, and can roll in a circular motion. Your elbow, however, only has one DOF, which is tilting up and down.
. . Scientists consider each of an octopus' eight arms to possess a virtually infinite number of degrees of freedom, allowing them to bend and twist freely. But when it's time to eat, octopuses use their flexible muscles to form temporary, quasi-articulated joints that work similar to how human joints function.
. . Researchers recorded muscle activity in octopus limbs, and found that an arm generates two waves of muscle contractions that propagate toward each other. When the waves collide, they form a part-time joint. This process occurs three times, forming a shoulder where the arm meets the body, a wrist where the suckers have grasped their food, and an "elbow" somewhere in between. The elbow typically exhibits the most movement during food retrieval.
. . The researchers say this is a remarkably simple and apparently optimal mechanism for adjusting the length of arm segments according to where the food item is grasped along the arm.
. . The similarity of structural features and control strategies between jointed vertebrate arms and flexible octopus limbs suggests that these configurations evolved separately in octopuses and vertebrates, a result scientists call an example of convergent evolution.

Apr 13, 06: A species of worm that thrives on undersea hot-water vents prefers the hottest water possible, choosing to live at temperatures that kill other animals, researchers reported. Their unique abilities to withstand hot water shooting like a geyser from hydrothermal openings may help the stalk-like worms prey on bacteria that other animals cannot reach.
. . The tiny worms, known scientifically as Paralvinella sulfincola, chose water heated to 50 degrees C (122 F) and made brief forays into water as hot as 55 degrees C (131 F). They belong to a group known as polychaetes and build tubes made out of mucus but can move around freely. They resemble tiny red palm trees, with frond-like red gills.
. . Many different animals live on the deep undersea vents, not merely tolerating the sulfur, heat and pressure but thriving in it. They eat the bacteria that can live in much higher temperatures than more complex animals.
. . The water pours out of the vents at temperatures far above the boiling point but it quickly cools in the chilly sea water. Because of the conditions, it is difficult to know precisely which temperatures the animals can tolerate.
. . The cells of complex animals all rely on structures called mitochondria, which provide power to the cells. Mitochondria start to break down at temperatures of 50 to 55 degrees C (122 to 131 F), Girguis said. The worms may skate on the borderlines of this limit, but do not break it.

Apr 12, 06: Swedish geologists have found fossilized feces from a worm that lived some 500 million years ago. They examined the level of phosphorus of the samples and that "we realized pretty soon that it could not be anything other than coprolites, in other words fossilized dung. It is inevitable to joke about this, so we gave it the title 'Anomalous faces and ancient feces'", Eriksson said.

Apr 12, 06: Fossils have long provided snapshots of the human family tree, but a new find in Africa gives scientists a kind of mini home movie showing man's primal development.
. . Because the 4.2-million-year-old fossil is from the same human ancestral hot spot in Ethiopia as remains from seven other human-like species, scientists can now fill in the gaps for the most complete evolutionary chain so far.
. . "We just found the chain of evolution, the continuity through time", said Ethiopian anthropologist Berhane Asfaw, co-author of the study. "One form evolved to another. This is evidence of evolution in one place through time. It's like 12 frames of a home movie, but a home movie covering 6 million years. The key here is the sequences", White said. "It's about a mile thickness of rocks in the Middle Awash and in it we can see all three phases of human evolution."
. . The species, Australopithecus anamensis is not new, but its location is what helps explain the giant leap from one early phase of human-like development to the next, scientists say. All eight species were found in a region called the Middle Awash.
. . Modern man belongs to the genus Homo [some say Pan (ape)], which is a subgroup in the family of hominids. What evolved into Homo was likely the genus Australopithecus (once called "man-ape"), which includes the famed 3.2 million-year-old "Lucy" fossil found three decades ago.
. . A key candidate for the genus that evolved into Australopithecus is called Ardipithecus. And Thursday's finding is important in bridging —-but not completely-— the gap between Australopithecus and Ardipithecus. "This appears to be the link between Australopithecus and Ardipithecus as two different species", White said. The major noticeable difference between the phases of man can be seen in Australopithecus' bigger chewing teeth to eat harder food.
. . Seven separate species have been named. Au. anamensis is the most primitive. The remains of the hominid that had a small brain, big teeth and walked on two legs, fits into the one million-year gap between the earlier Ardipithecus and Australopithecus afarensis which includes the famous fossil skeleton known as Lucy, which lived between 3.6 and 3.3 million years ago and was found in 1974.

Apr 15, 06: The fossils were found sandwiched between sediment layers containing the fossils of an earlier species, Ardipithecus ramidus, and the geologically younger Australopithecus afarensis.
. . This is the first time these three species have been found together in one geographic location and in such a tight chronological order, scientists say. The Middle Awash valley of Ethiopia has the longest and most continuous record of human evolution of any place on Earth. Scientists have found the fossils of nearly 250 hominid specimens embedded within more than a mile of stacked sediments representing time periods that stretch back 6 million years.
. . Since their remains don’t overlap, scientists think the three species are directly related, evolving one from the other, rather than being cousins that shared a common ancestor.

Apr 12, 06: Many amphibian moms provide their young with an egg yolk nutrient sac and then take off, leaving the kids to fend for themselves. Now scientists have found the world's most doting amphibians: mothers that let offspring eat the skin off their backs. Brooding Bolengerula taitanus moms transform their skin into a nutrient-rich meal for developing offspring. The youngsters squirm all over mom's body, peeling off the outer layer of skin with special teeth.
. . Scientists say this form of feeding, which doesn't hurt the mother unless the offspring get overly aggressive, is analogous to mammal lactation. The meals take a toll on mom, though—she weighs 14 percent less at the end of the week.
. . There are several benefits to this style of maternal care. Mothers save the large energy investment it takes to produce egg yolks. They also have the flexibility to delay providing food, or not provide any at all, if environmental conditions aren't favorable. And although these creatures produce fewer offspring than other amphibians, their young are larger and stand a better chance of survival.
. . Instead of laying eggs and feeding offspring externally, more advanced members of this amphibian group—called caecilians—give birth to live young. These offspring gain nourishment by eating the insides of the mother's womb-like organ. The new finding could provide a plausible intermediate step in the evolution from egg-laying to live-bearing amphibians.

Apr 12, 06: You might think a catfish on land would fare as well as an elephant on roller-skates, but a new study reveals they slither around and adeptly catch insect meals. The finding helps scientists imagine how ancient fish made their first hunting trips ashore prior to evolving into land creatures.
. . These particular eel catfish, Channallabes apus, live in tropical swamps in Africa, where most of the water is confined to small, acidic pools. The catfish pick up speed in water and flop onto land, where their flexible vertebral column lets them move around like a snake. They also have a special organ for breathing air without using their gills, although scientists don't quite know how this works.
. . In water, eel catfish suck in water to capture their prey. But because air is less dense than water, this trick is less effective when hunting on land, and these fish have developed a different approach. Once they find their terrestrial prey, usually a small beetle or insect, they lift their head and mash at the creepy-crawly with their mouth.
. . Having a mobile neck is key for hunting on land -—it allows the catfish to move its head up and down to stab at prey. Mobile necks are a feature usually reserved for land animals called tetrapods.
. . The best studied fish that feeds on land is the mudskipper. It feeds using a similar method to the catfish, but can use its pectoral fins to hop onto land and to lift and lower its head.
. . Recent discoveries of early tetrapods, such as Ichthyostega and Tiktaalik, have revealed that these beasts had mobile necks, and Van Wassenbergh said his catfish study might provide insight to how these early land animals went after food.
. . "It's hard to speculate about the behavior of fossils, but these animals had strong fins and a mobile neck, and I think there's a very good chance that these were also good terrestrial feeders", Van Wassenbergh said.
. . The Belgian researchers, writing in the journal Nature, hope this discovery will help to explain how fish moved from sea to land millions of years ago.
. . The researchers hope the discovery of another species of land-going fish will help shed light on how sea creatures evolved into land-living tetrapods during the Devonian Period, about 400 million years ago. They say C. apus bears similarities to fossils found from this period, including the recently described Tiktaalik rosea.
. . This creature, found in Arctic Canada, may be a "missing link" between sea and land-living animals.

Apr 11, 06: Leading scientists have warned against the teaching of creationism in schools, saying pupils must be clear that science backs the theory of evolution. The Royal Society statement comes after claims that some schools are promoting creationism alongside evolution. Meanwhile, delegates at the Association of Teachers and Lecturers' conference rejected calls for legislation to ban the teaching of creationism.
. . The Department for Education said that creationism was not taught in schools. "...young people are poorly served by deliberate attempts to withhold, distort or misrepresent scientific knowledge and understanding in order to promote particular religious beliefs." It added: "A belief that all species on Earth have always existed in their present form is not consistent with the wealth of evidence for evolution, such as the fossil record. Similarly, a belief that the Earth was formed in 4004BC is not consistent with the evidence from geology, astronomy and physics that the solar system, including Earth, formed about 4,600 million years ago."
. . Members will be asked to vote on calls for the government to legislate to prevent the growing influence of religious organisations in state schools and for it to stop funding faith schools.
. . The Archbishop of Canterbury, Dr Rowan Williams, said recently he was not comfortable with creationism being taught in schools.
. . A spokesman for the Department for Education and Skills said that neither creationism nor intelligent design were taught in schools.

Apr 10, 06: The Knoxville Zoo has joined a handful of zoos across the country with the strange creatures when it opened the "Naturally Naked Mole-Rats".
. . Natives of Africa, naked mole-rats are the only eusocial [like insects] mammals, meaning they live in a colony ruled by a queen, the only female who reproduces. In the wild, they spend nearly all their time underground, but despite their name they are neither moles nor rats. Mole-rats are more closely related to chinchillas, guinea pigs and porcupines.
. . There are several species of mole-rats, but only naked mole-rats are, well, naked or nearly hairless. Some other types are not eusocial and live alone or in smaller groups. Naked mole-rats are about 8 to 10 cm long and can look downright homely in large up-close photographs that emphasize their little to no hair, wrinkly skin and walrus-like teeth.

Apr 11, 06: Orchid bees swing their hind legs forward to reach top speed, a new study finds. The legs also generate lift, which keeps the bees balanced and helps prevent rolling. The hind legs resemble airplane wings.
. . It was just earlier this year that other researchers figured out how bees fly. To examine their flight mechanism more closely, Combes and colleagues encouraged the bees to fly in an outdoor wind tunnel by enticing them with aromatic oils.
. . They found that as speeds got higher, the bees extended their hind legs to maintain a stable position. But at the highest speeds, even those with fully extended legs reached their limit and lost their balance. This instability came from the rolling force on their legs.
. . Bee speed is limited not by muscle power or how high they can flap their wings, but on how they balance themselves during unstable conditions, the researchers found. The dangling legs help them keep their balance, similar to when a spinning figure skater extends her arms.
. . Understanding the mechanism of bee flight could help engineers design small flying machines for search and rescue missions or surveillance.

Apr 10, 06: New evidence suggests humans are evolving more rapidly --and more recently-- than most people thought possible. But for some radical evolutionists, Homo sapiens isn't morphing quickly enough.
. . "People like to think of modern human biology, and especially mental biology, as being the result of selections that took place 100,000 years ago", said University of Chicago geneticist Bruce Lahn. "But our research shows that humans are still under selection, not just for things like disease resistance, but for cognitive abilities."
. . Lahn recently published the results of a study demonstrating that two key genes connected to brain size are currently under rapid selection in populations throughout the globe. "The jury is still out on what this means because we aren't entirely sure what these genes do", said Lahn. "It's possible they just control size and shape of the brain, rather than cognition. But the data is pretty compelling that the brain is evolving."
. . Some radical thinkers suggest human evolution needs to move even faster, with a little help from science. "Biological evolution is too slow for the human species", said Ray Kurzweil, futurist and author of The Singularity Is Near. "Over the next few decades, it's going to be left in the dust."
. . He may be right, and not just because biotech researchers are racing to rewrite our genomes. Old-school theories that painted evolution as a glacial process have recently come under fire from researchers who see human evolution as a fast-paced and ongoing process.
. . Their work flies in the face of popular Darwinian theories of human behavior such as those espoused by Harvard University scientist Steven Pinker, whose recent book The Blank Slate takes for granted the idea that Homo sapiens hasn't changed since its long trek out of Africa 100,000 years ago.
. . "The time scale for a strongly favored mutation to sweep through a population is about 5,000 years", said Jonathan Pritchard, a University of Chicago evolutionary biologist. "It's hard to get an exact estimate for rates of change, but we know that the lactase gene is evolving the fastest in humans. It was new 5,000 years ago and now it's in virtually everybody in Europe."
. . The lactase gene is what allows humans to metabolize dairy products as adults. It's widely believed to have evolved in response to humans' domestication of dairy animals --individuals who could enhance their diet with dairy products had such a strong survival advantage that the gene spread at the speed of, well, several thousand generations.
. . Pritchard and his colleagues had found such overwhelming evidence that many human genes are evolving: not just ones that govern the brain, but also ones associated with reproduction, disease resistance and the ability to process certain kinds of foods.
. . Trans-humanist pundit James Hughes, author of Citizen Cyborg, thinks it's time to speed up the evolutionary process. "You can take what nature gave you, but there's no good reason to take nature as a guide for where you should go in the future", Hughes said.
. . "People are comforted by the slow pace of biological evolution", said Kurzweil. He predicted that "genetic reprogramming" will soon lead to "dramatic evolutionary changes."
. . Lahn, for his part, is a "moral relativist" on these issues, but does concede: "Human evolution could soon occur at a rate and with a set of rules that may be very different than what the Darwinian model has characterized so far."

Apr 10, 06: Scientists were excited to find that gene regulation of humans is different from chimps almost exclusively in the brain, and not in other organs like the liver or heart. That proves that the genetic differences are specific to the brain, and likely are associated with our higher cognitive function, Geschwind said.
. . "And that's allowed us and other people to show that there's been a lot of selective pressure and accelerated evolution in the brain", he added. The researchers also found that the genes were more often turned on, or "upregulated" in the human brain as opposed to the chimp brain.

Apr 9, 06: Australian scientists have discovered an "anti-freeze gene" that allows Antarctic grass to survive at minus 30 Celsius (-22 F), saying it could prevent multi-million-dollar crop losses from frost. "It's a gene from the saltgrass that managed to colonize the Antarctic peninsula called Antarctic Hairgrass."
. . "We identified a novel class of a gene protein which binds twice and that prevents ice crystal growth. It has the capacity to survive being frozen rock solid and then thawing. It prevents the damage from ice crystals."
. . Globally, between 5 and 15% of agricultural production is lost to frost each year.

Apr 9, 06: Crucian carp, a fish closely related to the goldfish, can live months without much oxygen, scientists have discovered. These freshwater fish, generally inhabitants of the lakes and rivers of Europe and Asia, are able to change the structure of their gills to boost oxygen uptake, allowing them to survive when they are for all practical purposes starved of oxygen. Additionally, their red blood cell hemoglobin, which transports oxygen, can bind oxygen to itself more strongly than in any other vertebrate.
. . Understanding the mechanism of how animals cope with oxygen starvation, called anoxia, could aid scientists solve similar problems in humans. "Anoxia related diseases are the major causes of death in the industrialized world", said Goran Nilsson, a professor at University of Oslo.

Apr 7, 06: The emergence of flowering plants 100 million years ago may have led to the explosion in ant diversity that occurred around the same time, scientists say. The 11,800 known species of modern ants probably arose from a single species millions of years ago, but scientists previously knew little about ants' evolutionary history.
. . Researchers analyzed the DNA of fossilized ants trapped in amber and discovered that the ancestors of modern ants first scurried along the ground 140 to 168 million years ago. These ants, however, were diversifying at a very slow rate. Then flowers, also known as angiosperms, sprouted onto the scene, and ants started diversifying like crazy. Other insects experienced a boom with the coming of flowers. These insects also lived among the debris, creating a massive new food source for ants.
. . These forests dropped more litter to the ground, creating more niches and complicated habitats for ants to specialize and diversify in. Today the greatest ant diversity is observed in plant debris and just under the soil. Forest canopies also provided interesting new homes for ants, including some that have learned to glide back to their home tree if they fall.
. . Today, ants account for an estimated 15 to 20% of the world's animal biomass. As scavengers, they keep the ground neat by munching on dead debris, and some scientists believe they turn over more soil than earthworms.

Apr 7, 06: Tucked into the cold shadows of the world's tallest mountain are biologically diverse hotspots filled with poorly known plants and animals found nowhere else on the globe.
. . Scientists from Conservation International and Disney's Animal Kingdom recently launched a two-month scientific expedition into six regions of the Tibetan "Sacred Lands" in the mountains of Southwest China and Nepal. Today they announced the discovery of a pocket of the world rich in extraordinary flora and fauna. Here's a sampling of the outlandish critters:
. . * Giant hornets so deadly locals call them "Yak Killers"
. . * Jumping "Yeti" mice
. . * A new grasshopper: the males hitch piggy-back rides on the females
. . * Baby blue-faced golden monkeys, the region's largest primates
. . * Hamster-like pikas that eat their own feces [as rabbits, as their intestines are too short.]
. . * A couple of new frog species, eight new insect species, and ten new species of ants to add the more than 11,000 already known.

Apr 5, 06: Even when they are starving rattlesnakes grow, eating themselves from within to gain length while reducing girth. This finding goes against previous reports that reptiles shrunk during lean times, as would be expected. The western diamondback rattlesnake can go two years without food.
. . Snakes starved for the entire period fed on their own stores, converting protein to carbohydrates. Calcium amounts doubled. "Because it takes more energy to grow than to eat yourself, the snake changes shape by reducing its girth and putting its resources into skeletal muscles and bone." Fatty acids also increased as the snakes fasted. Over time, however, hydrogen was drawn from the fatty acids as an energy source.
. . McCue's work could point toward ways to manipulate human diets. "We might be able to engineer diet so animals, and say humans in space, can tolerate food-deprivation better", he said.

Apr 5, 06: The lobster is the inspiration for a new type of European X-ray telescope. The observatory is designed to have an extremely wide field of view --just as the crustacean manages with its vision. The animal achieves this using a huge array of tiny channels that focus light by reflection, rather than by bending it through lenses found in human eyes.

Apr 5, 06: Fossils discovered in southern Utah are from a new species of birdlike dinosaur that resembled a 7-foot-tall brightly colored turkey and could run up to 25 mph. It was given the name Hagryphus giganteus, or giant four-footed, birdlike god of the Western desert. Fossils of the meat-eater's hand-like claw and foot were found in the Grand Staircase-Escalante National Monument near the Arizona border, giving paleontologists reason to believe some dinosaurs known as raptors roamed from Canada to northern New Mexico about 75 million years ago.
. . The dinosaur had a strong toothless beak, powerful arms and formidable claws that made it capable of eating animals and plants. Large feathers grew on its hind end, giving it a resemblance to a turkey, Zanno said. Scientists are not sure what purpose the feathers served, but it was not for flying. "It's quite different from modern birds", she said.

Apr 5, 06: Scientists have caught a fossil fish in the act of adapting toward a life on land, a discovery that sheds new light one of the greatest transformations in the history of animals. Scientists have long known that fish evolved into the first creatures on land with four legs and backbones more than 365 million years ago, but they've had precious little fossil evidence to document how it happened.
. . The new find of several specimens looks more like a land-dweller than the few other fossil fish known from the transitional period, and researchers speculate that it may have taken brief excursions out of the water. "It sort of blurs the distinction between fish and land-living animals", said one of its discoverers, paleontologist Neil Shubin of U of Chicago.
. . Experts said the discovery, with its unusually well-preserved and complete skeletons, reveals significant new information about how the water-to-land evolution took place. The new find includes specimens, 4 to 9 feet long, found on Ellesmere Island, which lies north of the Arctic Circle in Canada.
. . Some 375 million years ago, the creature looked like a cross between a fish and a crocodile. It swam in shallow, gently meandering streams in what was then a subtropical climate, researchers say. A meat-eater, it lived mostly in water. Yet, its front fins had bones that correspond to a shoulder, upper arm, elbow, forearm and a primitive version of a wrist, Shubin said. From the shoulder to the wrist area, "it basically looks like a scale-covered arm", he said. On land, it apparently moved like a seal.
. . The researchers have not yet dug up any remains from the hind end of the creature's body, so they don't know exactly what the hind fins and tail might have looked like.
. . The creature was dubbed Tiktaalik (pronounced "tic-TAH-lick") roseae, and also had the crocodile-shaped head of early amphibians, with eyes on the top rather than the side. Unlike other fish, it could move its head independently of its shoulders like a land animal. The back of its head also had features like those of land-dwellers. It probably had lungs as well as gills, and it had overlapping ribs that could be used to support the body against gravity, Shubin said.
. . Yet, the creature's jaws and snout were still very fishlike, showing that "evolution proceeds slowly; it proceeds in a mosaic pattern with some elements changing while others stay the same", Daeschler said.

Apr 3, 06: Last year, scientists working with physical DNA specimens published the sequence of a big chunk of a genetic code extracted from a frozen woolly mammoth bone. Another team recovered 40,000-year-old DNA fragments from cave bears. Other groups have gone after the DNA of extinct plants, insects, and even dinosaurs.
. . Wait a minute. Wasn't all this "ancient DNA" talk pretty well trashed after Jurassic Park? When an animal dies, DNA starts to break down like a cigar left in the rain, and, after the movie came out, scientists showed that amber-encased mosquitoes would never be able to provide enough dinosaur DNA to re-create a T. rex.
. . But the past few years have brought new developments. Scientists have gotten better at isolating DNA from fossils. They have also learned that perfectly preserved samples aren't necessary to build up lost genomes. Meanwhile, Haussler, benefiting from clever algorithms and massive increases in computing power, has made it much easier for them to fill in the gaps. Evolution tends to preserve exactly those parts that are most important.
. . Here's an analogy: You ask 10 friends to remember the letter G. But the next day you discover that some, including you, have forgotten it. When you ask all 10 what the letter was, four say "G", while the others choose random letters. Since "G" is the most common response, you can pretty safely assume that G is the letter you told them. Do the same thing several billion times with the DNA sequences of mammals that exist today and you should be able to determine the genome of the common ancestor from which those mammals evolved. The more genomes you feed into the model, the more accurate your result will be.
. . Biologists can give you lots of reasons why ur-mammals won't roam the earth again anytime soon. For starters, genomes are really long. A typical mammalian genome contains billions of base pairs. Geneticists have no idea, at present, how to construct DNA sequences of such length and insert them into cells.
. . There's another big issue: mistakes. Haussler estimates that he could determine the ur-mammal genome with 98% accuracy. But of course there's no way to double-check without the original DNA. Plus, 2% is a lot. A human genome that was 98% correct would still contain 120 million errors, any of which could cause horrific problems.
. . Reconstructing the genome of a Tyrannosaurus rex would therefore require inspired guesswork based on the genomes of related species like birds and turtles, as well as DNA fragments recovered from fossils. (And suddenly we're back in Jurassic Park.)
. . Researchers continue to get better at extracting DNA from fossils, and Haussler's reverse-engineering technique will become commonplace as more genomes from modern-day organisms are sequenced. According to Miller, within the next couple of centuries humans should be able to make any creature they want.

Apr 7, 06: Ants evolved far earlier than previously believed. Writing in the journal Science, the researchers said they reconstructed the ant family tree using DNA sequencing of six genes from 139 ant genera, encompassing 19 of 20 ant subfamilies around the world. Such "molecular clocks" are widely used, alongside fossil and other evidence, to determine how old species are. They work on the basis that DNA mutates at a steady and calculable rate.

Mar 29, 06: Worker wasps sometimes need to be encouraged to get off the couch, and the criticism of an unwilling worker can be biting. Researchers removed some active foragers from four wasp colonies to see how new foragers are recruited. The remaining wasps directed their biting at certain individuals who previously hadn't left the nest, apparently to encourage them to go find food. The rate of being bitten increased 600% for those that ended up being recruited as foragers.

Mar 29, 06: When it comes to making decisions, cockroaches take a Musketeer-like "all for one, and one for all" approach. Researchers offered 50 cockroach larvae their choice of three shelters that could each house more than 50 cockroaches. All 50 tended to crowd into the same shelter. When the shelters were swapped with smaller versions that could hold just 40 cockroaches, the group would typically split into two groups of about 25, leaving one house unoccupied. "It's better, in terms of group benefits, to have a 50/50 split instead of one important, large group and one that's less robust."
. . Group-living animals, such as flocks of birds, schools of fish, and colonies of ants, derive several benefits through this style of living. Cockroaches in particular enjoy increased reproductive success, they can share food resources, and they ward off desiccation by preserving humidity.
. . Interestingly, the group decides to divide without a leader telling everyone what to do. The decision is made collectively between individuals of equal status.

Mar 26, 06: Scientists in northeastern Ethiopia said that they have discovered the skull of a small human ancestor that could be a missing link between the extinct Homo erectus and modern man. The hominid cranium --found in two pieces and believed to be between 500,000 and 250,000 years old-- "comes from a very significant period and is very close to the appearance of the anatomically modern human."
. . Several stone tools and fossilized animals including two types of pigs, zebras, elephants, antelopes, cats, and rodents were also found at the site.
. . Homo erectus, which many believe was an ancestor of modern Homo sapiens, is thought to have died out 100,000 to 200,000 years ago. The cranium dates to a time about which little is known --the transition from African Homo erectus to modern humans. The fossil record from Africa for this period is sparse and most of the specimens poorly dated, project archaeologists said.
. . The face and cranium of the fossil are recognizably different from those of modern humans, but bear unmistakable anatomical evidence that it belongs to the modern human's ancestry, Sileshi said. Homo erectus left Africa about 2 million years ago and spread across Asia from Georgia in the Caucasus to China and Indonesia. It first appeared in Africa between 1 million and 2 million years ago. Between 1 million and perhaps 200,000 years ago, one or more species existed in Africa that gave rise to the earliest members of our own species Homo sapiens --between 150,000 and 200,000 years ago.
. . Delson said the fossil found in Ethiopia "might represent a population broadly ancestral to modern humans or it might prove to be one of several side branches which died out without living descendants."

Mar 24, 06: A hominid skull discovered in Ethiopia could fill the gap in the search for the origins of the human race, a scientist said today. The cranium is estimated to be 200,000 to 500,000 years old. The skull appeared "to be intermediate between the earlier Homo erectus and the later Homo sapiens." Significant archaeological collections of stone tools and numerous fossil animals were also found at Gawis. Sileshi said while different from a modern human, the braincase, upper face and jaw of the cranium have unmistakeable anatomical evidence that belong to human ancestry.
. . Over the last 50 years, Ethiopia has been a hot bed for archaeological discoveries. Hadar, located near Gawis, is where in 1974, U.S. scientist Donald Johnson found the 3.2 million year old remains of "Lucy", described by scientists as one of the greatest archaeological discoveries in the world.

Mar 22, 06: Can openers, scissors and spiral-bound notebooks discriminate against lefties. Despite such challenges, 10 to 12% of the human population has historically preferred the left hand. Why doesn't the number ever waiver? Nobody knows for sure, but new research supports a body of evidence that suggests genetics have a hand in it all. In the meantime, the myth remains that lefties are more artistic. And the idea that left-handed fighters have an advantage persists on scant evidence.
. . Like many traits, handedness is probably determined by a complex interaction between genes and the environment, experts figure. Left-handers are more likely to have a left-handed relative. But researchers have yet to find the gene or set of genes that pick one hand over the other. Most scientists agree that handedness exists on a continuum. The idea helps explain why some people bowl with their left but hold a spoon in their right. Truly ambidextrous people, who have indifferent preference for either hand, are extremely rare.
. . In a new study, researchers measured the width of elbows in living people and in skeletons from a medieval British farming community. The researchers assumed the 9-to-1 ratio of handedness would match the ratio of bigger right to left elbows. The prediction held true in the modern-day group, but not for the medieval bones. Most of the ancient farmers' left and right elbows were the same size. "It's obvious that they were using both hands equally. It's a behavior they may have learned rather than just being born like that."
. . Preference for handedness appears to take root in the womb, or even earlier. One genetic model, called the right shift theory, suggests that a single gene increases the likelihood of being right-handed. "The essence of my right shift theory is that there is a gene that helps to develop speech in the left hemisphere of the brain and increases the probability of right-handedness."
. . Whatever evolutionary jog made humans left-brain dominant for speech also made us right-side dominant, Annett argues. Since our closest relatives -—chimpanzees—- can't talk, the gene must have arisen in recent evolutionary history. One study found most chimps prefer to fish for termites with their left hand. But other recent research shows most chimpanzees favor their right hand when throwing overhand.
. . In a twist on the genetic model, the gene for hand preference might also be the gene for hair whorl direction, the way a person's hair turns on the top of their head. Half of people with counterclockwise whorls prefer their left hand, according to research by Amar Klar at the National Cancer Institute.
. . "The big myth is that the right side of the brain is somehow a creativity bull's-eye. That's not the case, and doesn't have anything to do with handedness. You need resources from both sides of your brain to be creative. All people use both sides of the brain", Wolman.
. . Lefties have had the upper hand in hand-to-hand combat since the Bronze Age, and even today, in the boxing ring. Left-handedness could be beneficial in times of violence, and genetically passed from one generation of fighters to the next. The Kerr family of Scotland, known for sinister swordsmanship, went so far as to build Ferniehirst Castle with an unusual staircase that spiraled counterclockwise. The architecture provided left-handed fighters more freedom to swing their sword.

Snails with left-handed shells can have a big advantage in life --predators may find it impossible to eat them. That is the conclusion of research just published in the Royal Society's journal Biology Letters.
. . Scientists from the US examined whelks and cone shells preyed on by the crab Calappa flammea. They found the crab is unable to open left-handed shells because it only has a tool for peeling them on its right claw; so it discards them. "The crabs have a special tool on their claw, a tooth that's used like a can-opener."
. . The evolutionary question is why these left-handed forms have remained so rare - some have even gone extinct --if they escape death by crab more easily. In some populations, they persist only in extremely low proportions, about 1%, or why in others they have gone extinct; other factors must be at play. Sinistral snails apparently find it much harder to find a mate, and so may be doomed to remain rare or die out completely, whether or not they evade can-opening crabs. [Yes, sinistral --where we get "sinister"-- means left-handed.]

Mar 22, 06: Worms, bacteria and beetles living below ground are part of the largest and least known trove of life on earth that could have spin-offs from farming to pharmaceuticals, a UN report said. "We know little of what is living below our feet...yet it is vital to sustaining life on earth."
. . French 19th century chemist and microbiologist Louis Pasteur was right to say that 'the role of the very small is large'.
. . Experiments in promoting natural organisms in soils --shifting from use of artificial pesticides and fertilizers-- had helped improve crop yields in some studies. In India, for instance, re-introduction of local earthworms had improved tea harvests at some plantations by almost 300%. In the Los Tuxtlas reserve in northern Mexico, bean yields had risen more than 40% after farmers started using a type of nitrogen-fixing microbe found in local forest soils as a "bio-fertilizer." Soil-burrowers such as termites --often dismissed as pests-- can help aerate soil and ensure that it can absorb water.
. . Creatures such as earthworms, fungi, termites, ants and bacteria could be "a potential source of new...pharmaceutical and industrial products", it said. Most bids to chart life on earth focus on rain forests, coral reefs or mangroves --overlooking humble mud.

Mar 22, 06: What goes on in a cocoon as a caterpillar changes into a butterfly remains one of nature's best kept secrets.But a new study reveals one part of the process: The insects burn a tremendous amount of fat while hibernating during the transformation.
. . It takes drastic chemical changes to morph a squirmy caterpillar into a beautiful butterfly, and scientists have estimated that this process requires loads of energy. While both the butterfly and larva diets and tissues had high concentrations of polyunsaturated fatty acids, the larva had nearly three times more fat than the butterfly.

Mar 22, 06: Most plants do their growing during the rainy season and stall out when it's dry. But in much of the Amazon rainforest, dry spells bring on growth spurts. The finding surprised scientists. "Most of the vegetation around the world follows a general pattern in which plants get green and lush during the rainy season, and then during the dry season, leaves fall because there's not enough water in the soil to support plant growth." The discovery holds true only for undisturbed parts of the rainforest.
. . What's going on? Deep roots of trees can reach water even in the dry season, the researchers figure, and so they take advantage of the added sunlight. Vegetation in areas that have been logged or converted to other uses can't reach the deep water, which might explain why it goes dormant or dies in the dry season.

Mar 20, 06: Scientists have identified a new dinosaur species that had one of the longest necks relative to body length ever measured. A typical neck bone in this creature was about the size of two loaves of bread. The species, Erketu ellisoni, belongs to the group of massive four-legged herbivorous dinosaurs called Sauropoda, the largest land animals ever to walk on Earth.
. . E. ellisoni had an extremely elongated neck. A single neck vertebra measures nearly two feet long, longer than the same vertebrae of the much larger Diplodocus carnegii.
. . Researchers estimate the neck was almost 7 meters long, all together. However, estimates of body size, based on limb bones and not including tail, indicate the body was probably about half as long as the neck.
. . Museums and movies have long reconstructed sauropods in postures similar to a giraffe -—with their heads held high, grazing hard-to-reach leaves. But based on how vertebrae fit together, recent studies and computer modeling suggest that these dinosaurs may actually have walked with their necks and heads held parallel to the ground. That doesn't mean that they couldn't lift their heads, Ksepka said, just that this is how it probably was in a relaxed pose.
. . The giant vertebrae also shed light on how sauropods managed life with the burden of such long necks. The sides of the bones feature large concavities where air sacs would have existed, and scans reveal that the bones are not solid, but filled with numerous small pneumatic chambers that would reduce weight. Also, unlike human vertebrae, the spines along the top of some vertebrae are split in two parallel tracks rather than one. This space may have been carved out for a ligament that helped support the neck. "It's not acting to lift the head up, though", Ksepka said. "It's acting like a bungee cord to provide support to keep the neck held in horizontal position without having to fire muscles."

Mar 18, 06: Depending on which journals you've picked up in recent months, early humans were either peace-loving softies or war-mongering buffoons. Which theory is to be believed?
. . A little bit of both, says Robert Sussman of Washington University, archaeologist, who warns against making generalizations when it comes to our long and varied prehistory.
. . The newest claim concerns Australopithecus afarensis, who lived approximately five million years ago and is one of the first hominids that can be linked directly to our lineage with some certainty. Hardly an expert at tearing other animals limb from limb, scientists say the small and furry creature likely spent most of its time avoiding becoming the lunch.
. . Groups of humans likely engaged in occasional violent encounters in order to increase their territory, argues Raymond C. Kelly of the University of Michigan. This may have continued up until about a million years ago, when distance weapons like the spear were invented and increased the risks of attacking other groups.
. . Human evolution just isn't that simple, says Michael Bisson, professor of anthropology at McGill University in Montreal, Canada. People tend to make generalizations about our early ancestors, even though they lived for a period of several million years and include many entirely different species of hominids.
. . As for the peaceful nature of Australopithecus afarensis, Bisson wholeheartedly agrees with Sussman. "Afarensis was small and completely non-technological. No one has ever argued that they were predatory. They are bipedal, ground-eating apes."
. . Interpretations get trickier, however, as time moves forward and hominids become more prevalent and diverse. When humans began to eat meat and use weapons, around two million years ago, some inter-group killings were almost certainly going on in the cases where individuals encroached on each other's territory. Still, at this point, hominids are mostly timid scavengers, according to Bisson, not mammoth-hunters.
. . "The interesting thing about early hominids and meat-eating is that all of the evidence we have for it is little animals that might have been caught and dismembered by hand and big animals that were scavenged", he said. "It fades in very slowly. After two million [years ago], there's about a half-million-year transition before you get to hunting of some kind."
. . It's around this time where mistakes can be made in the fossil record, experts say. With humans beginning to hunt animals, weapons in hand, it's easier to assume they are also killing each other. Puncture wounds in a skull from an animal bite can be mistaken as injuries from a spear attack, for example.
. . Sussman: "Human groups are much more likely to live in peace than in war", he explained. "What we usually find is that what is reported or emphasized is any violent encounter that takes place. Thus, instead of using the actual statistics, we emphasize the rare events." ... "A lot of this stuff was written between the First and Second World War", he reasoned. "It was very easy to see warfare and violence as inherent in the human condition during a period when humanity was literally trying to exterminate itself."
. . Mainstream media can also have a lot to do with what the public believes as fact. "No archaeologist in the last 40 years has bought the 'Killer Ape' interpretation, but it did get ingrained in popular culture in the intro sequence to the famous Stanley Kubrick film ["2001: A Space Odyssey"]", Bisson said. In the movie, ape-like humans are shown having the eureka moment that bones can be used as weapons, thus evolving to become hunters and killers. "It's a fairly literal dramatization of the hypothesis, complete with leg bones used as clubs."
. . Even if early humans were mostly cooperative with each other during the Paleolithic era-a period lasting about two million years-there is plenty of evidence to suggest that (like today), some people were just plain nasty. Cannibalism was clearly practiced in some areas, according to Bisson. "We know that there is at least one case of Homo erectus with extensive cuts on the cranium indicating that the person was essentially scalped and the eyes gouged out", he said.

Mar 17, 06: A beautifully preserved fossil from southern Germany raises questions about how feathers evolved from dinosaurs to birds, two paleontologists argue in a new study.
. . The 150 million-year-old fossil is a juvenile carnivorous dinosaur about 3/4 meter long that scientists named Juravenator, for the Jura mountains where it was found. It would have looked similar in life to the fleet-footed predators that menaced a girl on the beach during the opening scene of "The Lost World", the second Jurassic Park movie.
. . The fossil's exceptionally well-preserved bone structure clearly puts it among feathered kin on the dinosaur family tree. Because all of its close relatives are feathered, paleontologists would expect Juravenator to follow suit. But a small patch of skin on the creature's tail shows no sign of feathers. And the skin also doesn't have the follicles that are typical of feathered dinosaurs. The paleontologists believe Juravenator's closest known relative may have been a fully feathered dinosaur from China, Sinosauropterix.
. . There are a number of possible explanations for Juravenator's nakedness. Feathers could have been lost on the evolutionary line leading to Juravenator after arising in an ancestor to both it and its feathered relatives. Or feathers could have evolved more than once in dinosaurs, cropping up in sister species at different times and places. It is also possible that this particular fossil of Juravenator, which appears to be a juvenile, only grew feathers as an adult or lost its feathers for part of the year.
. . But there is another possibility as well, said Mark Norell, curator of paleontology at the American Museum of Natural History: It is entirely possible that Juravenator did have feathers, but they simply failed to fossilize. To support his hypothesis, he pointed out that several fossils of the oldest known bird, archaeopteryx, lack feathers.
. . Whether or not the new specimen raises interesting questions about how feathers —-and thus birds-— evolved, most experts do not see it as a challenge to the widely accepted view that modern birds are descended from dinosaurs.

Mar, 06: Researchers have found traces of a heat-loving bacterium that may live beneath a frozen lake in Antarctica.
. . Lake Vostok is covered by more than 3km of ice and must have been isolated from our planet's atmosphere for millions of years. The bacteria appeared in sediment mixed with a core of ice drilled by Russian and French researchers. The heat-loving, or thermophilic, bacterium may suggest that hydrothermal vents exist on the lake floor.
. . Meanwhile, a new ice core drilled this season may reveal whether there is also life in the lake itself. Hundreds of lakes exist beneath the thick Antarctic ice sheet, but with an area of 14,000 sq km Vostok is by far the largest. It has never been penetrated, but scientists know it is there through radar measurements taken from above.
. . Because Vostok sees no sunlight and has not been in contact with the atmosphere since it was covered with ice around 15 million years ago, scientists hope it might reveal the kind of life that could exist on other planets, or on Europa, the ice-covered moon of Jupiter.
. . The core was originally intended to study past climate, but although drilling stopped more than 100m above the lake's surface, the bottom parts of the core turned out to be frozen chunks of the lake water itself. Now a team of Russian and French scientists have used this core to investigate what the lake is truly like. So far they have found no definitive traces of life within Lake Vostok.
. . But the ice also contained streaks of dark sediment that they believe was thrust up from the lake floor by a small earthquake. In the sediment, the team found genetic traces of a bacterium that usually lives in temperatures of 50-60C. "We expected to find life adapted to a cold environment but instead we found exactly the opposite."
. . They compiled a list of microbes that could be found in their laboratory, and eliminated every one from their results. But the heat-loving bacterium appeared only in the ice core. In fact it is quite unusual, making the researchers even more confident that this one must have come from below the lake.
. . The Russians this season they returned to drill again at Vostok for the first time in eight years. By extending the Vostok drill hole to a depth of 3650m, a new world record, they managed to obtain an extra 27m of ice core. Since this ice comes from even closer to the water surface, it should reveal much more about the contents of this mysterious lake.

Mar, 06: A shrimp-like creature may have to forfeit its claim to be the longest abstainer from sex in the animal world. The discovery of three living male specimens casts doubt on the idea that the Darwinulidae family has been female and asexual for 200 million years. Darwinulids produce eggs which do not need to be fertilized by sperm.
. . But a team of scientists, writing in a Royal Society journal, cannot say yet whether the newly found males actually perform a sexual function. If they do not, if researchers can show the males are just some evolutionary hangover that is really no longer needed for reproduction --then the creatures will retain their famed celibacy status.
. . Darwinulids are fresh water crustaceans with a hinged shell. They measure less than a millimeter in length. Despite their diminutive size, however, they have an excellent fossil record. And it is from studying this long history that scientists believe females have been producing young without the need for fertilization from the Late Triassic onwards.
. . How these "ancient asexuals" persist is a mystery. Evolutionary theory suggests they should accumulate so many damaging genetic mutations (errors) over the generations that they would die out within 0.5-1 million years.

Mar 1, 06: The Age of Dinosaurs ended millions of years ago, but paleontologists are still attempting to get a handle on the immense diversity and diverse immensity of these creatures. Take the report last month that Spinosaurus is now officially the biggest carnivorous dinosaur known to science. This two-legged beast actually strode onto the fossil scene in 1915 when a specimen was described by German paleontologist Ernst Stromer. He figured this theropod (defined as a two-legged carnivore) was bigger than Tyrannosaurus rex, but the original Spinosaurus bones were destroyed by Allied bombs in 1944. So the T. rex reigned as the king size, carnivorous land beast for decades.
. . Then along came Giganotosaurus 11 years ago.
. . Now Cristiano Dal Sasso of the Civil Natural History Museum in Milan says Giganotosaurus has been dethroned based on estimates from a new Spinosaurus skull.
. . Tyrannosaurus rex: Length: 40-50 feet . Weight: 6 tons
. . Giganotosaurus Length: 47 feet . Weight: 8 tons
. . Spinosaurus: Length: 55 feet . Weight: 8 tons

For the ultimate in dinosaur length though, a vegetarian diet prevailed. Herbivorous sauropods dwarfed carnivorous theropod dinosaurs, and most scientists think Argentinasaurus was the longest of all dinosaurs.
. . Argentinasaurus: Length: 120 feet Weight: 100 tons

Mar 17, 06: When the American Museum of Natural History wanted to create a digital walking Tyrannosaurus rex for a new dinosaur exhibit, it turned to dinosaur locomotion experts John Hutchinson and Stephen Gatesy for guidance.
. . A computer model that assumes T. rex's hip, knee, ankle and main toe joints all flex and extend through a 90-degree arc yields more than 67 million possible poses. Most can be ruled out as structurally or biologically unlikely, but that still leaves thousands of possible configurations.
. . The researchers think that one way to narrow down the possibilities of dinosaur movement is to use more rigorous physical constraints in computer models. These constraints fall into two broad categories: kinematic (motion-based) and kinetic (force-based). One simple kinematic constraint, for example, is that the ankle and knee cannot bend backwards. "This approach can be used to reveal how dinosaurs did not move, moving us progressively closer to reconstructing what kinds of motions they may have used."

Mar 10, 06: Despite appearing to lumber around, reptiles that have been on this planet longer than any four-legged land creatures can actually run in a manner similar to more modern mammals.The new finding gives fresh insight to how four-legged animals got around way back when.
. . Researchers coaxed lizard-like tuataras, the oldest living lineage of four-legged land creatures, onto a treadmill and observed their gaits. A scale measured how much force the animals exerted on the ground with each step. The force measurements for both tuataras and salamanders revealed that they can walk and run, despite the outward appearance of a slow, lumbering gait.
. . Well, at least mechanically they run. Neither of these animals has what it takes to sprint, and their walking and running speeds are virtually identical and require the same amount of energy. The discovery also suggests that all terrestrial vertebrates can walk and run, except for turtles, which are hindered by their shells.

Mar 9, 06: Trout bred in captivity have smaller brains than those born in the wild, but scientists have recently discovered how to put hatchery-born fish brains on par with fish born in rivers. All it takes is a few stones. A little variety in the tank also produces fish that behave more like those born in the wild, which could increase the success rate of restocking rivers and streams.

Mar 9, 06: It has the face of a rat and the tail of a skinny squirrel --and scientists say this creature discovered living in central Laos is pretty special: It's a species believed to have been extinct for 11 million years.The long-whiskered rodent made international headlines last spring when biologists declared they'd discovered a brand new species, nicknamed the Laotian rock rat.
. . It turns out the little guy isn't new after all, but a rare kind of survivor: a member of a family until now known only from fossils. Nor is it a rat. This species, called Diatomyidae, looks more like small squirrels or tree shrews.
. . To reappear after 11 million years is more exciting than if the rodent really had been a new species, said George Schaller, a naturalist with the Wildlife Conservation Society. Schaller calls the area "an absolute wonderland", because biologists who have ventured in have found unique animals, like a type of wild ox called the saola, barking deer, and never-before-seen bats. Dawson describes it as a prehistoric zoo, teeming with information about past and present biodiversity. Now the challenge is to trap some live ones, and calculate how many still exist to tell whether the species is endangered.
. . Perhaps the best known example of the Lazarus effect is the coelacanth, a lobe-finned fish discovered off the coast of South Africa that scientists thought died out at least 65.51 million years ago. "It's the first time in the study of mammals that scientists have found a living fossil of a group that's thought to be extinct for roughly 11 million years. That's quite a gap. Previous mammals had a gap of only a few thousand to just over a million years."
. . The only difference is that the "living" specimen's teeth are slightly more pointed.

Bats are the second largest group of mammals (behind rodents) with about 1,000 known species. This figures, as the repro choices in caves are exclusive of other caves... among cave-dwelling species. [I'd guess, then, that there are many more species of them than tree-dwellers. JKH ]

Mar 8, 06: For nonpoisonous frogs, the trick to not becoming dinner is to look poisonous -—but not too poisonous, new research reveals.
. . Scientists studied three species of poison dart frogs in the Amazon rainforest in Ecuador. All three are blue with a speckling of red bumps on their backs. E. bilinguis also has yellow spots on its armpits. These colorful patterns tell predators that the frogs are toxic and would not make a good meal. Although A. zaparo can't actually back up this threat, its coloration fools predators into looking elsewhere for food.
. . In northern Ecuador, the benign A. zaparo coexist with E. parvulus, and over time have evolved to mimic their blue and red skin pattern. In southern Ecuador, where there are no E. parvulus frogs to imitate, A. zaparo frogs mimic the yellow-spotted E. bilinguis. The three species overlap in central Ecuador, and based on the rules of mimicry, scientists expected to see A. zaparo mimicking the more poisonous species. Instead, they found the non-toxic frogs only mimic the less poisonous species, E. bilinguis.
. . It turns out that mimicking the less poisonous species actually increases A. zaparo's chances of survival. Darst and her graduate professor Molly Cummings tested this strategy by offering all three species of frogs to hungry chickens. While chickens happily downed A. zaparo frogs, they spat out both poisonous varieties. The chickens took cues from these frogs' color patterns and learned to avoid poisonous frogs.
. . The chickens that tasted E. parvulus frogs generalized the experience to both variations that A. zaparo mimics. The chickens that learned only with the yellow-spotted E. bilinguis frogs, however, only passed on the A. zaparo frogs with similar yellow spots—E. parvulus-like frogs were fair game. "Therefore, predators who learned to associate either the bright colors of the less toxic or more toxic model frog species will avoid the mimic of the less toxic model frog. So, the mimic of the less toxic frog receives double the protection from predation."

Mar 8, 06: A comprehensive scan of the human genome finds that hundreds of our genes have undergone positive natural selection during the past 10,000 years of human evolution. Genes are the instructions organisms use to make proteins. They are encoded in genetic material, usually DNA, and some come in different versions, called “alleles". Positive natural selection occurs when one allele is favored over another due to changes in the environment.
. . “This study addresses the question 'Are humans still evolving?', and the answer is 'Absolutely,'" said study team member Benjamin Voight. “There have been a lot of recent changes -—the advent of agriculture, shifts in diet, new habitats, climatic changes—over the past 10,000 years."
. . Many genes were found to be evolving in all three of the human populations studied. The specific functions of many of the genes are not known, but the researchers were able to separate them into broad categories. These categories include:
. . * Olfaction: the researchers found many genes important for taste and smell
. . * Reproduction: involved in things like sperm mobility and egg fertilization
. . * Increasing brain size
. . * Bone development and skeletal changes
. . * Carbohydrate metabolism: positive selection was observed for genes involved in breaking down mannose in Yorubans, sucrose in East Asians, and lactose for Europeans. (Mannose is a sweet secretion found in some trees and shrubs, sucrose is common table sugar, and lactose is a sugar found in milk.)
. . * Disease resistance and pathogen protection
. . * Metabolism of foreign compounds, such as exotic plant proteins or animal toxins

The researchers also found positive selection in four pigment genes important for lighter skin in Europeans that were not known before. Scientists think humans evolved lighter skin in Europe as an adaptation to less sunlight. And in East Asians, they found strong evidence of positive selection in genes involved in the production of alcohol dehydrogenase (ADH), a protein necessary for breaking down alcohol. Many East Asians can't metabolize alcohol because they carry a mutation that prevents them from making ADH. The new finding suggests that the mutation may confer some currently unknown additional benefit.

Mar 8, 06: How can humans and chimpanzees, who share about 99% of the same genes be so different?
. . Scientists in the United States and Australia say changes in the gene expression, not just genes, is a big part of what separates humans from their nearest relatives. Gene expression is the process by which genes are turned on or off. Not all of the estimated 30,000 genes in humans are activated at the same time in every cell.
. . They used new gene-array technology to compare the level of expression of 1,056 genes in the four species. "We found fairly small changes in 65 million years of macaque, orangutan and chimpanzee evolution", said Dr Yoav Gilad of the University of Chicago, lead author. But he said it was followed by quick changes in specific groups of genes known as transcription factors, which control the expression of other genes, since humans diverged from their ape ancestors during the last 5 million years. "This rapid evolution in transcription factors occurred only in humans."
. . Until the mapping of the human genome and the development of gene array technology that allows for large-scale analysis of gene expression, it was not possible to test the hypothesis.
. . They found about 60% of the genes had consistent levels of expression in humans and the primates. But genes for transcription factors were more likely to have changed their expression patterns than the genes they regulate. "Specifically in the human lineage, the transcription factors are changing or evolving in their expression at a faster pace than in the other lineages, particularly as compared with chimps."

Mar 8, 06: A team of American-led divers has discovered a new crustacean in the South Pacific that resembles a lobster and is covered with what looks like silky, blond fur. Scientists said the animal, which they named Kiwa hirsuta, was so distinct from other species that they created a new family and genus for it.
. . The divers found the animal in waters 2500 meters deep at a site 1500 kms south of Easter Island last year. It's white and 15cms long.
. . In what Segonzac described as a "surprising characteristic", the animal's pincers are covered with sinuous, hair-like strands. It is also blind. The researchers found it had only "the vestige of a membrane" in place of eyes. The researchers said that while legions of new ocean species are discovered each year, it is quite rare to find one that merits a new family.

Mar 6, 06: A baby Triceratops skull suggests the impressive horns of the beast were for more than just attracting a mate.
. . An adult Triceratops skull, 2 meters long, dwarfs the .3 meter skull of a year-old Triceratops. The three-horned Triceratops dinosaur weighed up to 10 tons and had one of the largest skulls of any land animal on the planet. Now the smallest skull of the species suggests what the horns were for.
. . "The baby Triceratops confirmed our argument that the horns and frill of the skull likely had another function other than sexual display or competition with rivals, which people have often argued, and allows us to propose that they were just as important for species recognition and visual communication in these animals", said paleontologist Mark Goodwin at the University of California at Berkeley.
. . The young one was about one year old and a meter long. As with many young animals, it had a short nose compared to the adults.
. . Triceratops horridus was a North American dinosaur, though relatives roamed China and Mongolia during the Cretaceous period, 144 million to 65.51 million years ago. An adult Triceratops could be nearly 10 feet tall and 26 feet long, with a bony frill around the head up to 7 feet across. Two meter-long horns typically curved forward from the brow. A third horn rose from the nose above a narrow, horny beak.
. . The surface of the skull shows grooves were blood vessels used to be, perhaps to nourish a fingernail-hard covering of keratin similar to the thicker layer that covers an adult skull. Such horny coverings are often brightly colored in birds, which are thought to be descendents of dinosaurs. That suggests Triceratops may have been colorful, too. The two brow horns are straight and about an inch long in the baby. The brain casing had not yet fused in the young beast. "The baby skull shows us how the bones that make up the skull actually grew and fit together, because we see the sutures and sutural surfaces, which were completely obliterated in the adults."

Mar 6, 06: A review of dog bites treated at a trauma center in Austria over a 10-year period found that children aged 1 and younger ran the highest risk of being bitten though anyone up to age 10 runs a higher risk than in later years. "Parents should postpone purchase of a dog until children are of school age", the study said. "Throughout evolution, dogs have lived in packs with a specific order of dominance. In view of this rigorous hierarchal system in a pack, dogs may regard newborns as well as toddlers as subordinate."
. . The researchers said they found that the relative risk of being bitten by a German shepherd or a Doberman was about five times higher than for a Labrador retriever or a mixed breed.

Mar 6, 06: Although they have brains about the size of a grain of rice, hummingbirds have superb memories when it comes to food, according to research. No bird-brains these tiny creatures that weigh 20 grams (0.7 ounces) or less and feed on nectar and insects. The research suggests they not only remember their food sources but can plan with a certain amount of precision. They found that the birds remembered where specific flowers were located and when they were last there, two aspects of episodic memory which was thought to be exclusive to humans.
. . "Hummingbirds that defend territories of many flowers remember which flowers they have recently emptied." The scientists tracked how often hummingbirds visited eight artificial flowers filled with a sucrose solution in the birds' feeding grounds. They refilled half the flowers at 10 minute intervals and the other half 20 minutes after they had been emptied. The birds' return to the flowers matched the refill schedules: flowers refilled at 10-minute intervals were visited sooner.
. . Scientists suspect the brains of hummingbirds became highly developed because of their long travel schedules and so they do not waste time and energy searching for food.

Mar 7, 06: When sagebrush is damaged by insects, it broadcasts the predator's presence by releasing odors into the air. Other sagebrush pick up on the smells from their wounded brethren and get their defenses going. Turns out wild tobacco plants eavesdrop on these signals. The tobacco uses the knowledge to fortify its own defenses. Then it waits to deploy the arsenal if and only if the insect attacks. By holding off on deployment, the tobacco retains vital energy for other important tasks. The proteins and chemicals used for defense contain nitrogen and carbon, which also are needed to produce seeds. It's a classic guns vs. butter tradeoff.
. . The discovery that tobacco could intercept signals from sagebrush came as a surprise, however. The two species rarely share the same habitat, and with rare exceptions, the same creatures rarely eat both plants.

Mar 7, 06: Students at Singapore Polytechnic say they have created a plant that can communicate with people --by glowing when it needs water. The students said that they have genetically modified a plant using a green fluorescent marker gene from jellyfish, so that it "lights up" when it is stressed as a result of dehydration. The light is hard to detect with the naked eye but can be seen using an optical sensor. The development of such plants could help farmers to develop more efficient irrigation of crops.

Mar 7, 06: The discovery of a Turkish family that walks on all fours could aid research into the evolution of humans. Researchers believe the five brothers and sisters, who can walk naturally only on all fours, may provide new information on how humans evolved from four-legged hominids to walk upright. "It has produced an extraordinary window on our past. It is physically possible, which noone would have guessed from the [modern] human skeleton."
. . The siblings, the subject of a new BBC documentary to be aired on March 17, suffer from a genetic abnormality that may prevent them from walking upright. Instead, they use their palms like heels with their fingers sticking up from the ground.
. . The BBC said the documentary would contribute to fierce scientific debate and raised profound questions about what it is to be human.
. . Two sisters and one son have only ever walked on two hands and two feet, while another daughter and son occasionally walk on two feet. All five are mentally retarded and have problems with language as a result of a form of underdevelopment of the brain known as cerebellar ataxia.

Mar 4, 06: A Mexican marine biologist has discovered a new shark species in the murky depths of Mexico's Sea of Cortez, the first new shark find in the wildlife-rich inlet in 34 years.

Mar 2, 06: The verdict is in: apes are cultured. Fifty years of research on gorillas, chimps and orangutans has shown they use tools, communicate, and sometimes shake their hands just because it’s cool.
. . Ecologist Kinji Imanishi first introduced the concept of culture in a non-human species in 1952. He suggested that Japanese macaque populations develop behavioral differences as a result of social, rather than genetic, variation.
. . Of all the species studied to date, only humans exceed the level of cultural variation shown by chimps.
. . Last August, scientists confirmed culture in chimps in a study that found chimps naturally copy their peers well into adulthood, suggesting they develop cultural behaviors by imitating each other.
. . Armed with previous field research, as well as new studies from wild orangutans and captive gorillas, researchers have more evidence to explain the variation and transmission of cultural behaviors in apes. Scientists are now focusing on the details of cultural behaviors and how apes adopt them as tradition. Like us, apes are influenced by popular opinion. Scientists have observed cultural traditions that last for generations, and some that look more like short-term trends.
. . Traditions between groups vary, similar to human cultural differences. In the wild, one group of orangutans living by a river pounds stones and branches to crack open nuts. Living just across the river are apes that, by chance, haven’t picked up the nut-cracking technique. Cracking nuts is one of more than 40 behavior patterns scientists have observed that does not appear to have any genetic explanation.
. . Cultural behaviors stem from popularity, the environment the apes are in, and pure chance. Apes like being with other apes; orangutans will actually suppress aggression when in groups. Even bullies will chill out so they don’t pass up an opportunity to play with others.
. . Yet food shortages force individuals to spend lots of time foraging on their own. The less time an ape can spend with others, the fewer behaviors it can learn. The size of the local cultural repertoire relates directly to the amount of time spent with other animals, van Schaik said. Orangutans live in areas with less food than chimps, which explains why cultural behaviors in orangutans tend to be less elaborate than those of chimpanzees. In zoos, apes have access to all the food they need and plenty of socializing.

Mar 2, 06: In isolated habitats, competition among species is limited. The consequence is that, with time, predator species tend to get smaller while prey species grow larger. The optimum size (at least for mammals) seems to be roughly that of a rabbit.

Mar 2, 06: Oops, the scientist dropped his clothespin. Not to worry —-a wobbly toddler raced to help, eagerly handing it back. The simple experiment shows the capacity for altruism emerges as early as 18 months of age. Toddlers' endearing desire to help out actually signals fairly sophisticated brain development, and is a trait of interest to anthropologists trying to tease out the evolutionary roots of altruism and cooperation.
. . Psychology researcher Felix Warneken performed a series of ordinary tasks in front of toddlers, such as hanging towels with clothespins or stacking books. Sometimes he "struggled" with the tasks; sometimes he deliberately messed up.
. . Over and over, whether Warneken dropped clothespins or knocked over his books, each of 24 toddlers offered help within seconds — but only if he appeared to need it. Video shows how one overall-clad baby glanced between Warneken's face and the dropped clothespin before quickly crawling over, grabbing the object, pushing up to his feet and eagerly handing back the pin.
. . Warneken never asked for the help and didn't even say "thank you", so as not to taint the research by training youngsters to expect praise if they helped. After all, altruism means helping with no expectation of anything in return. And —-this is key-— the toddlers didn't bother to offer help when he deliberately pulled a book off the stack or threw a pin to the floor.
. . To be altruistic, babies must have the cognitive ability to understand other people's goals plus possess what Warneken calls "pro-social motivation", a desire to be part of their community. "When those two things come together —-they obviously do so at 18 months of age and maybe earlier-— they are able to help."
. . But babies aren't the whole story. No other animal is as altruistic as humans are. We donate to charity, recycle for the environment, give up a prime subway seat to the elderly —-tasks that seldom bring a tangible return beyond a sense of gratification.
. . Other animals are skilled at cooperating, too, but most often do so for a goal, such as banding together to chase down food or protect against predators. But primate specialists offer numerous examples of apes, in particular, displaying more humanlike helpfulness, such as the gorilla who rescued a 3-year-old boy who fell into her zoo enclosure.
. . But observations don't explain what motivated the animals. So Warneken put a few of our closest relatives through a similar helpfulness study. Would 3- and 4-year-old chimpanzees find and hand over objects that a familiar human "lost"? The chimps frequently did help out if all that was required was reaching for a dropped object —-but not nearly as readily as the toddlers had helped, and not if the aid was more complicated, such as if it required reaching inside a box.
. . It's a creative study that shows chimps may display humanlike helpfulness when they can grasp the person's goal, University of California, Los Angeles, anthropologist Joan Silk wrote in an accompanying review. Just don't assume they help for the reasons of empathy that motivated the babies, she cautioned.

Felix Warneken was in a tough spot. While hanging laundry, he had "accidentally" dropped a clothespin out of reach. Stretch as he might, he couldn’t grab it. He even cried out, "My pin!" A young chimpanzee sitting nearby picked up on Warneken’s distress and retrieved the clothespin for him. Since the chimp received no reward, or even a "thank you", this experiment indicates chimps can be altruistic, a quality many scientists thought only humans possessed. If Warneken threw the pin deliberately, neither chimps or humans would pick it up. While infants helped on a variety of tasks, the chimps weren’t as willing to help with some of the more difficult chores.
. . In another study in the journal, researchers observed that when a task requires more than one set of hands, chimps call on "experts" to help out. Researchers placed a food tray outside the chimp’s cage. Pulling on a both ends of a rope attached to the tray was the only way to bring the food within reach. But the ends were so far apart that the chimp had to enlist a helper.
. . "The experiments show that chimpanzees spontaneously recognize that when they are faced with a problem they cannot solve on their own they need to recruit help", said study coauthor Brian Hare of the Max Planck Institute. The chimps quickly figured out which chimp was best at rope-tugging and selected the expert more frequently.
. . Soviet experiments in the 1920s were designed to produce a human-chimpanzee hybrid (in an attempt to discredit religion, while simultaneously offending chimp family values). It failed.
. . As recently as 1931, you could observe caged humans (Africans and Inuit were favorites) on display in Europe.

Feb 27, 06: Public schools won't have to change the way they teach evolution, after the House today gutted, and then killed, a bill that would have required science courses to mention alternative theories.

Feb 27, 06: Every year, millions of Mormon crickets swarm in a frenzied search for food. Turns out the dinner plate is often heaped with their slower brethren. Mormon crickets aren't actually crickets, but shield-backed katydids, a type of insect more closely related to grasshoppers.
. . Although scientists don't fully understand the mechanism that organizes and coordinates when and where the swarm moves, they have figured out why. Each migration is typically associated with an actual or anticipated food shortage and a population increase.
. . During one such migration across the Curlew National Grasslands of southern Idaho, researchers plucked a few study participants from the half-mile long swarm to see just what they were hungry for. The insects were deficient in both protein and salt, and snacked on food items rich in these nutrients. The menu included seed pods, flowers, dead animals, mammal feces, and soil soaked in cattle urine. Sometimes after shedding their outgrown exoskeleton, they eat that too. But some hungry crickets can't wait for the exoskeleton to fall off, and simply devour the guy molting next to them. "The insects themselves provided a major source of these nutrients, and cannibalism was rife."
. . The scientists intentionally hindered the mobility of some crickets and found that these slowpokes were the most likely to be eaten. Freshly dead crickets are also a favorite meal. However, feeding the crickets a steady diet of proteins and salts curbed their cannibalism. Furthermore, protein-satiated crickets were no longer compelled to march.

Feb 23, 06: The discovery of a furry, beaver-like animal that lived at the time of dinosaurs has overturned more than a century of scientific thinking about Jurassic mammals. The find shows that the ecological role of mammals in the time of dinosaurs was far greater than previously thought, said Zhe-Xi Luo, curator of vertebrate paleontology at Carnegie Museum of Natural History in Pittsburgh. The animal is the earliest swimming mammal to have been found and was the most primitive mammal to be preserved with fur.
. . Now, a research team that included Luo has found that 164 million years ago, the newly discovered mammal with a flat, scaly tail like a beaver, vertebra like an otter and teeth like a seal was swimming in lakes and eating fish. An important factor is how specialized the creature was.
. . Thomas Martin of the Research Institute Senckenberg in Frankfurt, Germany, said the discovery pushes back the mammal conquest of the waters by more than 100 million years. It's the first evidence that some ancient mammals were semi-aquatic, indicating a greater diversification than previously thought, the researchers said. Modern semi-aquatic mammals such as beavers and otters and aquatic mammals like whales did not appear until between 55 million years ago and 25 million years ago. The new animal is not related to modern beavers or otters but has features similar to them.
. . The researchers found imprints of the fur, both guard hairs and short, dense under fur that would have kept water from the skin. Weighing in at between 1.1 and 1.7 pounds, about the size of a small female platypus, Castorocauda is also the largest known Jurassic early mammal.

Feb 23, 06: Australian researchers have discovered a natural mosquito repellent in the smelly secretions of green tree frogs. Chemicals released through the skin of the frogs produces a pungent smell that wards off mosquitoes. "The smell is just not very good. Some smell of rotting flesh, some of nuts, some of thyme leaves." Green tree frogs were the first known back-boned animals to have a natural trick to protect them from mosquitoes.
. . The frog secretions were tested on mice, and were found to give up to one-hour's protection from aggressive mosquitoes. But Williams said he did not expect the findings would lead to a new frog-based mosquito repellent for humans. "In the concentrations you would need, it would not smell good enough."

Feb 22, 06: Scientists have discovered a mutant chicken with a full set of crocodile-like chompers. The mutant chick, called Talpid, also had severe limb defects and died before hatching. It was discovered 50 years ago, but no one had ever examined its mouth until now. The researchers recently created more Talpids by tweaking the genes of normal chickens to grow teeth.
. . The oldest reptiles, such as crocodiles and alligators, had cone-shaped teeth. So did the earliest birds, called archosaurs. Then, around 80 million years ago, modern birds emerged without teeth. Indeed, Talpid's teeth are conical, much like an archosaur's and closely resembling the teeth of a baby alligator or crocodile, Fallon said. If the chick survived, the teeth would most likely reabsorb into the mouth.
. . The archosaurs had mouths similar in shape to a reptile's. It turns out that developing a beak caused birds to lose their teeth. "The reason that birds lost their teeth is that in forming a beak, the two tissues that ‘talk' to each other to make a tooth become separated", Fallon said. "They can't have the conversation to make a tooth. In the mutant, these tissues are brought back together."
. . By making a few changes to the expression of certain molecules in the pathway, the researchers were able to induce tooth growth in normal developing chickens. These teeth also looked like reptilian teeth and shared many of the same genetic traits, supporting the scientists' hypothesis. None of these chickens were allowed to hatch.

Feb 22, 06: Neandertals in Europe were killed off by the advance of modern humans thousands of years earlier than previously believed, losing a competition for food and shelter, according to a scientific study. The research uses advances in radiocarbon dating to revise understanding of early humans, suggesting they colonized Europe more rapidly and coexisted for a much shorter period with genetic ancestors.
. . Paul Mellars, professor of prehistory and human evolution at the University of Cambridge and author of the study: "The two sides were competing for the same territories, the same animals and fuel supplies and occupying the same cave spaces. With that kind of competition, the Neandertals were always going to come out as the losers."
. . Modern humans —-those anatomically the same as people today-— were also better equipped to deal with a 6 degree Celsius (11 Fahrenheit) fall in temperatures around 40,000 years ago. "Because they had better clothing, better technology and a better mastery of fire, the humans were equipped to deal with it."
. . Humans and Neandertals, thought to have coexisted for 10,000 years across the whole of Europe, are more likely to have lived at the same time for only 6,000 years.
. . Scientists believe the two species could have lived side by side at *specific sites for periods of only about 2,000 years, but Mellars claims they would have lived in competition at each site for only 1,000 years. Mellars claims the first modern humans arrived in the Balkans from Israel around 46,000 years ago, about 3,000 years earlier than thought. His study claims they were able to spread west to the Atlantic coast in around 2,500 to 3,000 years, about 1,000 years quicker than believed.
. . Mellars used the results of two recent studies of radiocarbon dating to refine dates determined from fossils, bone fragments and other physical evidence that relates to the spread of humans. The two new studies of stratified radiocarbon in the Cariaco Basin, near Venezuela, and of radiocarbon on fossilized coral formations in the tropical Atlantic and Pacific have given scientists a better idea of the amount of carbon in the atmosphere over the last 50,000 years. In turn, that work allows researchers to more accurately convert carbon years into calendar years, by taking into account variations in atmospheric carbon.

Feb 21, 06: A tiny worm that lives in glaciers and snowfields is drawing attention for what it could reveal about life on other planets. The ice worm inhabits glacial regions in the coastal ranges of Alaska, British Columbia, Washington and Oregon. The odd creature easily moves through ice, is liveliest near the freezing point of water and dissolves into a goo when warmed. There's been increased interest in ice worms and other animals whose glacial habitat could disappear within the next 50 years due to global warming.
. . National Geographic funded one of the first field surveys to focus on ice-worm ecosystems. NASA last year provided $200,000 to explore the worms' cold tolerance and what it might say about the possibility of life on Jupiter's icy moons and other planets. That work could also improve cold storage of organs and tissues for transplantation. The NASA project focuses on a key enzyme that regulates the worms' energy cycle.
. . Hartzell believes the worms travel through tiny fissures in the ice, but other scientists have suggested the worms secrete a substance that melts a path, like a warm knife through butter.
. . The downside is extreme sensitivity to heat. At about 40 degrees F, the worms' membranes melt and their enzymes go haywire.
. . Around sunset during warm weather, the black worms are hard to miss as they swarm to the surface to feed on algae, pollen and other digestible debris. "In some places, they're so thick you can't step without killing tons of them."
. . In winter, when algae can't grow and snow blankets the surface, Lee suspects the worms stay deep inside the ice, perhaps going dormant.

Feb 18, 06: Captive gorillas actually are a cultured bunch. Genetics or environment alone cannot explain variations in the behavior of different groups of the apes, a study found. Behavioral surveys of the roughly 370 gorillas in U.S. zoos showed 48 variations in how individual groups of the apes make signals. "What became very obvious is there is a very distinct pattern of similarities and differences between groups", Stoinski said. That suggests the gorillas pass along the different traits socially, not genetically, which is a hallmark of culture.
. . Researchers previously have found that other ape species —-including chimpanzees and orangutans-— show cultural differences as well in how they forage, use tools and court one another. At Zoo Atlanta, only some gorilla groups use sticks to push aside the electrified wires that protect the trees in their enclosures, allowing the apes to snack on the bark without getting shocked, she said. As for chimps, recent videos, described by Whiten, show the apes in the Congo using a "tool kit" to collect and eat termites.

Feb 18, 06: A group of New Zealand school children have found the remains of what is believed to be a 40 million-year-old "giant" penguin, a report said. Bones from the largest ancient giant penguin, found in New Zealand more than 130 years ago, indicate the bird stood about 1.5 meters (five feet) tall and weighed more than 100 kilograms (220 pounds).

Feb 18, 06: The popular view of our ancient ancestors as hunters who conquered all in their way is wrong, researchers have told a major US science conference. Instead, they say, early humans were on the menu for predatory beasts. This may have driven humans to evolve increased levels of co-operation, according to their theory. Despite humankind's considerable capacity for war and violence, we are highly sociable animals, according to anthropologists.
. . James Rilling at Emory University in Atlanta, US, has been using brain imaging techniques to investigate the biological mechanisms behind co-operation. He has imaged the brains of people playing a game under experimental conditions that involved choosing between co-operation and non-co-operation. From the parts of the brain that were activated during the game, he found that mutual co-operation is rewarding; people reacted negatively when partners did not co-operate. Dr Rilling also discovered that his subjects seemed to have enhanced memory for those people that did not reciprocate in the experiment. By contrast, our closest relatives --chimpanzees-- have been shown not to come to the aid of others, even when it would pose no cost to themselves.
. . "Our intelligence, co-operation and many other features we have as modern humans developed from our attempts to out-smart the predator", said Robert Sussman of Washington University in St Louis.
. . According to the theory espoused by Professor Sussman, early humans evolved not as hunters but as prey for animals such as wild dogs, cats, hyenas, eagles and crocodiles. He points to the example of one ape-like species thought to be ancestral to humans, Australopithecus afarensis. A. afarensis was what is known as an "edge species"; it could live in trees and on the ground, and could take advantage of both. "Primates that are edge species, even today, are basically prey species, not predators."
. . Dr Agustin Fuentes at the University of Notre Dame agrees with the predation hypothesis. He believes early humans were subject to several evolutionary pressures, including predation. But he also thinks they were expending more energy at this time and that child-rearing became more demanding. All these factors contributed to an emergence of sociable behavior in hominids that made them harder targets for predators.

Feb 18, 06: Straight out of the womb, infants are just as aroused by a rhesus monkey call as by human speech. Infants are acute listeners. Previous studies have found newborns perk up more to folk music than white noise. And four-month-olds like listening to people talk more than they like white noise. But when it comes to sounds made by all things biological, newborn babies don't discriminate.
. . In light of other research, the results are surprising. For instance, scientists have seen changes in fetal heart rates when its mother talks, which suggests the fetus reacts to hearing the mother's voice. The recent findings imply that an infant's first preference for sounds comes not just from experiences it had while inside the womb. Rather, a baby's listening skills might be honed to human speech during the first few months of life outside the womb.
. . By three months, babies are aroused more by speech than monkey calls. The results indicate that we may be born with a broad preference for biological sounds, which gets rapidly fine-tuned for species-specific language. "If these babies spent the first three months with rhesus monkeys, maybe they'd prefer monkey calls."

Feb 17, 06: New methods of analyzing fossils have scientists arguing more than ever about whether Tyrannosaurus rex was a lumbering scavenger or a swift and agile predator. A CAT scan study of Tyrannosaurus rex skulls shows it had the inner ear of a much smaller, swifter predator. But a close look inside its thigh bone shows it had the ungainly body of a heavier creature. "I think what we have to do now is re-model dinosaurs", said Jack Horner.
. . They used CAT scans to look at the skulls of more than 100 dinosaur fossils. "It turns out that inner ear provides some very important clues about behaviors (and) also about their relative movements -- how agile they were or how stately they were", Witmer told a news conference. "The hearing part is long and delicate in T. rex, suggesting that it could potentially discriminate sounds effectively and that hearing was important behaviorally." The inner ear also gives clues as to posture and shows that T. rex held its head in an alert, forward-looking position, while Diplodocus looked down, presumably to graze. And T. rex seems to have an enlarged brain region that is associated with a sense of smell in modern animals, Witmer said. "This is interesting because T. rex was a gigantic animal. T. rex actually had some very heightened senses", Witmer said. "It also strongly employed relatively rapid turning movements of its eyes and head."
. . But Horner found evidence that T. rex was not as lithe as such measurements would suggest. His team has been cutting into the fossilized leg bones of the dinosaurs, which lived during the last part of the Cretaceous period, 85 million to 65.51 million years ago, in what is now western North America. They found soft bone tissue and within it, the nuchal ligament, which connects the vertebrae. "We took a microsection through the bone and there it was --soft tissue", Horner said. "We were surprised." The structure appeared to have been very stiff, Horner said. "I am not arguing with Larry (Witmer) on his information about the ear. But it is really odd that we have an animal that looks like it should be agile but isn't. It is one of those puzzles that we have with dinosaurs."
. . Horner believes that T. rex was a scavenger, in part because its fossil skeletons are so common. "Top predators are rare", Horner said. And it had bone-crushing teeth. "If you are an animal that does the killing, you don't need to crush bone. You just eat the meat and leave", Horner added. Perhaps T. rex was a predator as a juvenile and turned into a scavenger as it aged, Horner suggested. "I don't have any problem with it moving its head around", he added. But Horner, one of the world's leading experts on dinosaurs, said there is no evidence they were ever as fast or agile as, say, a modern ostrich.

Feb 17, 06: Brain size and the ability to walk upright efficiently are two of the main attributes that separate humanity from the apes. Now researchers say learning to walk millions years ago was not without its trials. A re-examination of anklebones from early hominids indicates their gait was not as stable as previous research suggested. They were knock-kneed.
. . A group of species known as robust australopithecines lived about 2 million years ago. Compared to us, they had larger teeth and stronger chewing muscles, a stouter skull with a smaller brain. Their feet were thought to be very much like ours, suggesting they had mastered bipedalism. "By looking at the location where the shin bone rides across the anklebone, we found that the shin bones would have been angled inward."
. . Human ancestors go back as far as 6 million years, fossils show. The genus Homo arose at least 1.8 million years ago, scientists believe, when australopithecines likely evolved into human ancestors known as Homo habilis, which had larger brains but never grew larger than a 12-year-old child of today.
. . The results support the idea that bipedalism evolved only once. "The skeletal modifications associated with bipedalism represent a phenomenal reorganization of one's anatomy", Schwartz said. "It is unlikely that it could have evolved independently in multiple hominin lineages." But that doesn't mean the transition was smooth. The researchers have no idea how being knock-kneed might have been an advantage, but they plan to explore the question next.

Feb 15, 06: The apocryphal tale that you can't grow new brain cells just isn't true. Neurons continue to grow and change beyond the first years of development and well into adulthood, according to a new study. The finding challenges the traditional belief that adult brain cells, or neurons, are largely static and unable to change their structures in response to new experiences.
. . The study, performed in adult mice, found that the branch-like projections on some neurons, called "dendrites", were still physically malleable. Dendrites conduct electrical signals received from other neurons to the parent neuron's cell body. The changes occurred both incrementally and in short bursts, and involved both growth and shrinkage.
. . Other studies looking into adult neuron growth focused mainly on excitatory pyramidal neurons, but the MIT study examined other neuron types as well. The researchers found that while pyramidal neurons didn't exhibit any structural changes -—which is consistent with previous reports—- a group of inhibitory neurons called "interneurons" did. The researchers estimate that on average, about 14% of the interneurons they observed showed structural modifications. Approximately 20 to 30% of the neurons in the neocortex, the part of the brain responsible for higher functions such as thought, are made up of inhibitory interneurons. These neurons are believed to play an important role in regulating brain activity by delaying or blocking signals from excitatory neurons. The researchers speculated whether interneurons might be largely responsible for neural plasticity in adult brains.

Feb 15, 06: Cane toads in Australia have developed longer legs to enable them to invade more territory, scientists said. "We find that toads with longer legs can not only move faster and are the first to arrive in new areas, but also that those at the front have longer legs than toads in older populations." The scientists believe the toads evolved longer legs to conquer new territory to get to better food supplies.
. . They added that efforts to control the pests should be launched before the toads evolve into even more dangerous adversaries. The poisonous toads, which are a threat to native species, were introduced into Australia 70 years ago to control insect pests in sugar cane fields. They have since spread across one million square kilometers in the north and east of the country and have become one of the continent's worst environmental disasters.

Feb 14, 06: Scientists have discovered what they believe is a new fish species and at least 20 types of previously unknown seaweeds during a recent expedition to one of the Caribbean's most diverse marine areas —-a coral-covered underwater mountain off the Dutch island of Saba.

Feb 14, 06: Life on Earth was unlikely to have emerged from volcanic springs or hydrothermal vents, according to a leading US researcher. Experiments carried out in volcanic pools suggest they do not provide the right conditions to spawn life. "The results are surprising and in some ways disappointing. It seems that hot acidic waters containing clay do not provide the right conditions for chemicals to assemble themselves into 'pioneer organisms.'"
. . Professor Deamer said that amino acids and DNA, the "building blocks" for life, and phosphate, another essential ingredient, cling to the surfaces of clay particles in the volcanic pools. "The reason this is significant is that it has been proposed that clay promotes interesting chemical reactions relating to the origin of life", he explained. "However, in our experiments, the organic compounds became so strongly held to the clay particles that they could not undergo any further chemical reactions."

Feb 14, 06: Researchers scouring the remote forests of the African island nation of Madagascar have found that tiny assassin spiders, grotesque-looking bugs that prey on other spiders, are more diverse than previously thought. The nine newly discovered species could shed light on how assassin spiders evolved, and perhaps point scientists to other places in Madagascar where other types could be located.
. . The bizarre-looking assassin spiders were once widely found around the world, but now are found in Madagascar, Australia and South Africa. They grow to less than an eighth of an inch long, are notorious for stabbing helpless spiders with their sharp, venom-filled fangs attached to their super-sized jaws. Assassin spiders also possess very long necks so they can attack their prey from a distance. They do not spin webs to entrap their prey and they pose no threat to humans.

Feb 14, 06: After long suspecting we're born with some math sense, researchers have shown infants indeed have some ability to count long before they can demonstrate it to Mom and Dad. It turns out they're not unlike grown monkeys.
. . In the study, seven-month-old babies were presented with the voices of two or three women saying "look." The infants could choose between looking at a video image of two or women saying the word or an image of three women saying it. The babies spent significantly more time looking at the image that matched the number of women talking. "We conclude that the babies are showing an internal representation of 'two-ness' or 'three-ness' that is separate from sensory modalities and, thus, reflects an abstract internal process."

Jan 26, 06: As you scream for your favorite sports team, special brain cells kick in to protect your auditory system from the sound of your own voice, a new study suggests. These cells dampen your auditory neurons' ability to detect incoming sounds. The moment you shut up, the inhibition signal stops and your hearing returns to normal, so you can then be deafened by the screams of the guy next to you.
. . Scientists call this signal a corollary discharge. This could help explain why we can't tickle ourselves. "The corollary discharge is not present when someone else tickles us", Poulet explained. "Therefore the sensory response in the brain is much greater and the tickle appears much more ticklish."

Jan 25, 06: Researchers have found that the shape of the human skull has changed significantly over the past 650 years. Modern people possess less prominent features but higher foreheads than our medieval ancestors.
. . Writing in the British Dental Journal, the team took careful measurements of groups of skulls spanning across 30 generations. The scientists said the differences between past and present skull shapes were "striking".
. . They looked at 30 skulls dating from the mid-14th Century. "The astonishing finding is the increased cranial vault heights. The increase is very considerable. For example, the vault height of the plague skulls were 80mm, and the modern ones were 95mm --that's in the order of 20% bigger, which is really rather a lot."
. . He suggests that the increase in size may be due to an increase in mental capacity over the ages.

Jan 26, 06: Computer scientists in Canada have worked with botanists in Switzerland to build a 3D computer model which simulates how plants grow and develop beautiful shapes. Their model was able to accurately show how plants achieve phyllotaxis, this regular arrangement of lateral organs around a central axis. According to the researchers, this model will be used by botanists to complement and interpret laboratory experiments. But it also could be used as a basis for models of how other organisms, including animals, develop from primordial stem cells.
. . They created a three-dimensional simulation of plant growth at the microscopic scale, simulating cell division and showing how concentrations of the fundamental plant growth hormone auxin appear at regularly-spaced intervals. This creates the striking spiral patterns of seeds observed in sunflowers, daisies, and many other plants. Other patterns, such as branching at right angles observed in lilac branching, can be also be simulated using different parameter values.

Jan 25, 06: The war continues —a battle for the ages. Which side will win -—arachnids and other insects with sticky feet, or the slippery slopes of passive carnivorous plants like the pitcher plant? Actually, materials scientists who study both sides are the real winners.
. . Human beings have spent a lot of time looking for perfectly frictionless surface coatings. Just as the stickiest surfaces have been found on the feet of natural creatures like geckoes and spiders, slippery surfaces have also been found in the natural world. The carnivorous pitcher plant uses an especially slippery slope to catch prey. The plant has a lid, a peristome (a ring around the trap entrance), a slippery zone and a digestive zone.
. . The plant walls of the slippery zone are covered with a double layer of crystalline wax. The upper layer has crystalloids which contaminate the attachment organs that insects use to adhere to surfaces. It is made of single, irregular 30-50 nanometer platelets standing more or less perpendicular to the plant wall.
. . The lower layer is similar to foam, being made of connected membrane-like platelets which stick out at sharp angles and offer no clear orientation. This layer further reduces the contact area between insect feet and plant surface.

Jan 25, 06: Land snails, not the quickest of creatures, managed to travel from Europe to remote islands in the South Atlantic by hitching rides on birds. Scientists had assumed that snails living on the Tristan da Cunha islands midway between South Africa and Brazil were a different species from those in Europe but researchers in the Netherlands and Britain have shown they belong to the same family.

Jan 24, 06: Apes have a knack for evolving more quickly than we do. A study in 2003 found that 99.4% of important DNA sites are the same in chimps and humans. Other researchers have since concluded that there are crucial differences in the genetic software of the two species, however. Only a few months ago was the full chimp DNA sequence unraveled.
. . In the new study, scientists examined how quickly each species evolves. The figure they work with is called a molecular clock. It involves the rate at which DNA base pairs match up incorrectly, creating genetic errors called substitutions. These are the mutations that cause changes in a species over time. Our clock began to slow down about 1 million years ago, and today it is 3% slower than that of the chimp and 11% slower than in the gorilla, concludes the study, led by Soojin Yi, a biologist at the Georgia Institute of Technology.
. . The upshot: There seem to be fewer changes to the software of life in humans over time than in chimpanzees, and even fewer still than in the other apes. This slower clock correlates with a longer time needed to reach sexual maturity—almost twice as long for humans as gorillas. Scientists call this "generation time." In order for mutations to cause lasting change in a species, they must pass on to the next generation.
. . "I think we can say that this study provides further support for the hypothesis that humans and chimpanzees should be in one genus, rather than two different genus' because we not only share extremely similar genomes, we share similar generation time", Yi said.

Jan 24, 06: Chimpanzees may be more closely related to human beings than they are to other apes. Scientists at the Georgia Institute of Technology said they found genetic evidence that chimpanzees may be more closely related to humans than to gorillas and orangutans. Soojin Yi and colleagues looked at mutations in the so-called molecular clock, using the mutation rate in DNA. "Intriguingly, both humans and chimpanzees appear to have evolved slower than gorillas and orangutans."
. . "Humans take almost twice as long to reach sexual maturity as chimpanzees (Pan troglodytes) and gorillas (Gorilla gorillas), have a longer lifespan, and have a longer gestation period as compared to any nonhuman hominoid", the researchers wrote. Their molecular clock suggests humans evolved this trait just a million years ago. Humans and chimpanzees are believed to have diverged from a single common ancestor about 7 million years ago.

From The Economist:
. . It was Spencer who invented that poisoned phrase, "survival of the fittest". He originally applied it to the winnowing of firms in the harsh winds of high-Victorian capitalism, but when Darwin's masterwork, “On the Origin of Species”, was published, he quickly saw the parallel with natural selection and transferred his bon mot to the process of evolution. As a result, he became one of the band of philosophers known as social Darwinists. Capitalists all, they took what they thought were the lessons of Darwin's book and applied them to human society. Their hard-hearted conclusion, of which a 17th-century religious puritan might have been proud, was that people got what they deserved—albeit that the criterion of desert was genetic, rather than moral. The fittest not only survived, but prospered. Moreover, the social Darwinists thought that measures to help the poor were wasted, since such people were obviously unfit and thus doomed to sink.
. . As a result, Darwinism had to tiptoe round the issue of how human society and behavior evolved. Instead, the disciples of a second 19th-century creed, Marxism, dominated academic sociology departments with their cuddly collectivist ideas—even if the practical application of those ideas has been even more catastrophic than social Darwinism was.
. . Modern Darwinism's big breakthrough was the identification of the central role of trust in human evolution. People who are related collaborate on the basis of nepotism. It takes outrageous profit or provocation for someone to do down a relative with whom they share a lot of genes. Trust, though, allows the unrelated to collaborate, by keeping score of who does what when, and punishing cheats.
. . Very few animals can manage this. Indeed, outside the primates, only vampire bats have been shown to trust non-relatives routinely. [you may've read me say elsewhere that I consider bats as primates. JKH] The human mind, however, seems to have evolved the trick of being able to identify a large number of individuals and to keep score of its relations with them, detecting the dishonest or greedy and taking vengeance, even at some cost to itself. This process may even be—as Matt Ridley described it -—the origin of virtue.
. . Competition, whether athletic, artistic or financial, does seem to be about genetic display. Unfakeable demonstrations of a superiority that has at least some underlying genetic component are almost unfailingly attractive to the opposite sex. Thus both of the things needed to make an economy work, collaboration and competition, seem to have evolved under Charles Darwin's penetrating gaze.
. . This is a view full of ironies, of course. One is that its reconciliation of competition and collaboration bears a remarkable similarity to the sort of Hegelian synthesis beloved of Marxists. Perhaps a bigger one, though, is that the Earth's most capitalist country, America, is the only place in the rich world that contains a significant group of dissenters from any sort of evolutionary explanation of human behavior at all. But it is also, in its way, a comforting view. It suggests a constant struggle, not for existence itself, but between selfishness and altruism—a struggle that neither can win. Utopia may be impossible, but Dystopia is unstable, too, as the collapse of Marxism showed. Human nature is not, to use another of Spencer's favourite phrases (though one he borrowed from Tennyson, his poetical contemporary), red in tooth and claw, and societies built around the idea that it is are doomed to early failure.
. . Of the three great secular faiths born in the 19th century --Darwinism, Marxism and Freudianism-- the second died swiftly and painfully and the third is slipping peacefully away. But Darwinism goes from strength to strength. If its ideas are right, the handful of dust that evolution has shaped into humanity will rarely stray too far off course. And that is, perhaps, a hopeful thought to carry into the New Year.

Jan 25, 06: Scientists have discovered the world's smallest fish on record in an acidic peat swamp in Indonesia, with a see-through body and a head that is unprotected by a skeleton, researchers said. Mature females of the Paedocypris progenetica, a member of the carp family, only grow to 7.9 millimeters (0.31 inches) and the males have enlarged pelvic fins and exceptionally large muscles that may be used to grasp the females during copulation.
. . The fish live in dark, tea-colored water with an acidity of ph 3, at least 100 times more acidic than rainwater. Swamps like this were once thought to harbor very few animals, but recent research has revealed that they are highly diverse and home to many species that occur nowhere else.
. . Peat swamps are under threat in Indonesia from fires lit by plantation owners and farmers as well as unchecked development and farming. Several populations of Paedocypris have already been lost.

Jan 24, 06: For some male bats, sexual prowess comes with a price —-smaller brains. A research team led by Syracuse University biologist Scott Pitnick found that in bat species where the females are promiscuous, the males boasting the largest testicles also had the smallest brains. Conversely, where the females were faithful, the males had smaller testes and larger brains. The study offers evidence that males —-at least in some species-— make an evolutionary trade-off between intelligence and sexual prowess. "Bats invest an enormous amount in testis, and the investment has to come from somewhere. There are no free lunches."
. . Bats are the second largest group of mammals (behind rodents) with about 1,000 known species. Pitnick's team looked at 334 species of bats and found a convincing contrast in testes size. In species with monogamous females, males had testes starting at 0.11% of their body weight and ranging up to 1.4%. But in species where the females had a large number of mates, Pitnick found testes ranged from 0.6% to 8.5% of the males' mass. "If female bats mate with more than one male, a sperm competition begins", Pitnick said. "The male who ejaculates the greatest number of sperm wins the game, and hence many bats have evolved outrageously big testes."
. . Promiscuity is known to make a difference in testicle size in some other mammals. For example, chimpanzees are promiscuous and have testicles that are many times larger than those of gorillas, in which a single dominant male has exclusive access to a harem of females.
. . Large brains, meanwhile, are metabolically costly to develop and maintain. Pitnick's research suggested that in those bat species with promiscuous females, the male's body used more of its energy to enhance the testes —-giving it the greater adaptive advantage-— and lacked the energy it needed to further develop the brain. The study found that in more monogamous species, the average male brain size was about 2.6% of body weight, while in promiscuous species, the average size dipped to 1.9%. [in bats, the weight is critical to flight, as well.]

Jan 24, 06: When times are tough, women tend naturally to abort a higher percentage of male fetuses. Researchers call it culling, but they don't know why it occurs. This much is known: During times of social or economic stress, a woman's liver tends produces more of a hormone called cortisol that proves so damaging to male fetuses they actually kick out in response to it. Female fetuses, more vital on the whole, seem relatively unaffected by the cortisol.
. . One theory states that damage to male fetuses is a side effect of this hormonal stress response. But in a new study, researchers provide evidence for the other theory, that the body is purposely culling the males by pumping out cortisol in an effort to get rid of a child-to-be that is less likely to survive the presumably difficult situation outside the womb. The key to the research is this: Male embryos and fetuses are known to be weaker. So trying to bring a boy into this world under hardship would be disadvantageous, in terms of survival of the fittest, compared to having a girl.
. . Ralph Catalano and Tim Bruckner at the University of California, Berkeley, examined records of Swedes born between 1751 and 1912 to see under what conditions they came into the world and how long they lived. Those born during bad economic times and other periods of high stress -—male or female—- actually had longer life spans, "suggesting the weaker among them were removed" in the fetal stage. And since more of the males would naturally have been week, slamming them with the hormone would be a biologically beneficial way of quickly preparing the mother for another pregnancy instead of possibly wasting time on a birth that would not produce an ideally healthy child. They suggest the hormonal reaction to stress was retained by women specifically because it increases the chances their genes will be passed on to subsequent generations.

Jan 20, 06: Twenty-seven previously unknown species of spiders, centipedes, scorpion-like creatures and other animals have been discovered in the dark, damp caves beneath two national parks in the Sierra Nevada, biologists say. "Not only are these animals new to science, but they're adapted to very specific environments —-some of them, to a single room in one cave." [even w bats, caves are isolated genepools.]
. . The discoveries included a relative of the pill bug so translucent that its internal organs are visible, particularly its long, bright yellow liver. There was also a daddy long legs with jaws bigger than its body, and a tiny fluorescent orange spider.
. . The species have yet to be named, described scientifically and placed in the continuum of known living organisms.

Jan 20, 06: Amazonian hunter-gatherers who lack written language and who have never seen a math book score highly on basic tests of geometric concepts, researchers said in a study that suggests geometry may be hard-wired into the brain. Adults and children alike showed a clear grasp of concepts such as where the center of a circle is and the logical extension of a straight line, the researchers report.
. . They tested 14 children and 30 adults of an Amazonian group called the Munduruku, and compared their findings to tests of U.S. adults and children. "Munduruku children and adults spontaneously made use of basic geometric concepts such as points, lines, parallelism, or right angles to detect intruders in simple pictures, and they used distance, angle, and sense relationships in geometrical maps to locate hidden objects."
. . Geometry is an ancient field and Dehaene's team postulated that it may spring from innate abilities. "Many of its propositions --that two points determine a line, or that three orthogonal axes localize a point-- are judged to be self-evident and yet have been questioned on the basis of logical argument, physical theory, or experiment." There was no way the Munduruku could have learned these ideas, they added. "Most of the children and adults who took part in our experiments inhabit scattered, isolated villages and have little or no schooling, rulers, compasses, or maps. Furthermore, the Munduruku language has few words dedicated to arithmetical, geometrical, or spatial concepts, although a variety of metaphors are spontaneously used."
. . "The spontaneous understanding of geometrical concepts and maps by this remote human community provides evidence that core geometrical knowledge, like basic arithmetic, is a universal constituent of the human mind", they concluded.

Jan 19, 06: Your ability to hear relies on a structure that got its start as a gill opening in fish, a new study reveals. Humans and other land animals have special bones in their ears that are crucial to hearing. Ancient fish used similar structures to breathe underwater. Scientists had thought the evolutionary change occurred after animals had established themselves on land, but a new look at an old fossil suggests ear development was set into motion before any creatures crawled out of the water.
. . The transition: Researchers examined the ear bones of a close cousin of the first land animals, a 370-million-year-old fossil fish called Panderichthys. They compared these structures to those of another lobe-finned fish and to an early land animal and determined that Panderichthys displays a transitional form. In the other fish, Eusthenopteron, a small bone called the hyomandibula developed a kink and obstructed the gill opening, called a spiracle. However, in early land animals such as the tetrapod Acanthostega, this bone has receded, creating a larger cavity in what is now part of the middle ear in humans and other animals.
. . It's unclear if early tetrapods used these structures to hear. Panderichthys most likely used their spiracles for ventilation of either water or air. Early tetrapods probably passed air through the opening. Scientists would need preserved soft tissue to say for sure. "That's the question that we're starting to investigate, whether early tetrapods used it for some ventilation function as well", Brazeau said. Whether it was for the exhalation of water or air, it's not really clear. We can infer that it's quite expanded and improved from fish."

July 28, 04: [Ok, it's out of time-place, but I just found it.] Ground squirrels make an alarm call so high pitched that we cannot even hear it, scientists report in Nature. While studying the little rodents, researchers noticed that some of them made faint whispering sounds, as if they had lost their voices. But when these "silent screams" were processed by a bat detector, an abundance of ultrasound was detected. The researchers believe the whispers might be "secret" alarm calls --that the squirrels' predators cannot hear.
. . The problem is that the sounds are used by rodents in all sorts of situations; and they elicit all sorts of responses. So it is hard for observers to unravel the circumstances under which these calls are used. Now, at last, researchers have detected an ultrasonic call with, they think, a clear meaning.
. . James Hare and his colleague David Wilson analyzed the high-pitched calls, and found they were made in reaction to a threat; and elicited an alarm response in other squirrels. Richardson's ground squirrels also make audible alarm calls, which seem to raise a more dramatic response in the "audience". So the researchers speculate that whisper calls might indicate a slightly lower level of threat.
. . They think that the squirrels might have evolved ultrasound so they can communicate with their neighbors without any predators knowing about it. Also, ultrasonic screams are very targeted. So a squirrel can selectively call to its kin without anyone else hearing.
. . Ultrasonic communication is probably far more prevalent in the animal world than we know because, simply, we cannot hear it. A rare Chinese frog has entered the record books as the first amphibian known to communicate using ultrasound. Until now, only a few mammals --such as bats, whales and dolphins-- have been found to use the very high frequency sound to contact each other. The frog may have evolved the mechanism to be heard above the babble of running water, scientists tell this week's edition of the journal Nature. The frog lives alongside fast-flowing streams in Anhui Province, China. During the rainy season, the water level rises dramatically, creating a noise that drowns out the calls of many small animals.
. . A team led by Albert Feng, a US professor, visited the bank of China's Tao Hua Creek in search of the frog. They heard the warbling melody of what they thought was a bird coming from some undergrowth. It turned out to be the song of a male frog of the very species they wanted to study. The team recorded a frog's calls, split them into their constituent frequencies and tested other frogs' responses to them in the wild. They found that most of the frogs responded to ultrasonic and audible sound ranges, half of them sending back their own ultrasonic and audible calls in response.
. . The fact that it has been found in amphibians, which are on a different evolutionary pathway from mammals, suggests it has evolved several times independently.
. . The electromagnetic sense in fishes and homing pigeons, polarized light vision in ants, chemical sensing of pheromones in insects and rodents, echo-location by ultrasound in bats and dolphins, are just a few examples of other senses.

Bats are the second largest group of mammals (behind rodents) with about 1,000 known species. [This figures, as the repro choices in caves are exclusive of other caves... among cave-dwelling species. I'd guess, then, that there are many more species of them than tree-dwellers. JKH ]

Cave wolf spiders share a special adaptation —-their spiderlings have a row of comb-like teeth on their claws that perfectly match the spaces on the multi-branched hairs found on the mother's back. This match allows the spiderlings to hold on for safe transport and protection by the mother.

Jan 13, 06: Newborn adult brain cells travel along a neural highway from their place of birth to their final destination. Now scientists have shown that tiny, beating, hair-like structures called cilia play an important role in helping the new cells merge onto the highway's on-ramp.
. . Scientists have long questioned how newborn brain cells manage to migrate long distances in the adult brain and arrive at the right place. By studying the movement of newborn neurons inside adult mouse brains, a team of international scientists figured it out. This is the first study to show that cilia help control cell migration in the adult mouse brain as well as the developing brain. Researchers suspect the setup is similar in humans.
. . Cilia help move stuff in other parts of the body too. They control flow of mucus and fluids in your windpipe, or trachea. They move eggs from ovaries to the fallopian tubes. They also help direct cell migration during development of a new organism, making sure cells destined to become toes and ears end up on your feet and head, respectively.

Jan 13, 06: Stem cells play a key role in the deer's remarkable ability to grow new antlers, according to research. The deer is unique among mammals in being able to regenerate a complete body part --in this case a set of bone antlers covered in velvety skin. They grow in three to four months, making them one of the fastest growing living tissues. After the antlers have reached their maximum size, the bone hardens and the velvety outer covering of skin peels off. Once the velvet is gone, only the bare bone remains --a formidable weapon for fighting. At the end of the mating season, the deer sheds its antlers to conserve energy. Next spring, a new pair grows out of a bony protuberance of tissue at the front of the animal's head.
. . The research suggests that stem cells --the master cells of the body, with the ability to develop into many specialized cell types-- underpin this process. It is mediated by some sort of signalling pathway, probably regulated by hormones such as estrogen and testosterone.
. . Experts at the Royal Veterinary College hope the work could one day lead to new ways to repair damaged human tissues. The long-term goal of the work is to better understand the chemical signalling pathway behind the process of regeneration, in the hope that it can be harnessed by human medicine to develop novel treatments for diseases such as Parkinson's. 'Can we make this signal come on again if we have an injured or severed (human) tissue?'

Jan 12, 06: An American researcher believes he has solved the mystery of how one of the most important human ancestors died nearly 2 million years ago: An eagle killed the 3 1/2-year old ape-man known as the Taung child. The discovery suggests small human ancestors known as hominids had to survive being hunted not only by large predators on the ground but by fearsome raptors that swooped from the sky, said Lee Berger, a senior paleoanthropologist at Johannesburg's University of the Witwatersrand.
. . The discovery of the partial skull of a juvenile ape-man in South Africa's North West Province in 1924 revealed a human ancestor species called Australopithecus africanus. "We had one little flap of bone on the top of the skull that looked like some of the damage we see made by eagles and nothing else. ... It was the ultimate 2 million-year-old cold case." The next step was to put the Taung skull next to the Tai monkey skulls and look at the break edges more closely. So far, only photographs have been used.
. . Yes, we used to be bird food. This murder most fowl occurred 2 million years ago. Placing us on the eagle's menu may also explain other aspects of human evolution, from walking upright, which could present a smaller target to an aerial attacker, to our tendency to live in groups. "Birds of prey are one of the few things that some modern primates have special calls or alarms for."

Jan 11, 06: Ants teach other ants how to find food using a poking and prodding technique called "tandem running", a new study reveals. Researchers say the experiment reveals the first non-human example of formal instruction between a teacher and pupil in which there is two-way feedback and an adjustment of the course curriculum.
. . When female worker ants of the species Temnothorax albipennis set out for food, they often find another ant to make the journey with. If the second ant doesn't know where to find food, the leader teaches her through tandem running.
. . Studies have shown that bumblebees can learn to find food by watching others, and that chimpanzees can teach their mates how to get at food with a stick. But the researchers say this is the first non-human example of bidirectional feedback teaching—where both the teacher and pupil modify their behavior to provide guidance at a rate suitable for the pupil's abilities.
. . Getting directions from a lead ant helped the followers find their way to food much more quickly -—on average 201 seconds with help, versus 310 seconds without. But showing the way is costly for the lead ants, which can move nearly four times faster on their own. It takes longer partly because the followers make large loops as they go, probably in search for landmarks to find their way back with. Information then flows through the ant colony when followers are promoted to leaders and the teaching process starts all over again.
. . "Teaching isn't merely mimicry. It involves the teacher modifying its behavior in the presence of a naive observer at some initial cost to itself."

Jan 10, 06: Scientists found a new class of cells in the eye that are sensitive to light responsible for regulating the body's circadian clock.
. . The eye's retina contains light receptors known as cones and rods. These receptors receive light, convert it to chemical energy, and activate the nerves that send messages to the brain. They were thought to be the only photoreceptors in the retina of the eye.
. . "When we began to do our work, we knew there might have been a missing photoreceptor", said David Berson, professor of neuroscience at Brown University. "We asked ourselves if there is a third class, and the answer turned out to be yes." The discovery was made with mice, whose eyes are thought to function similarly to humans.
. . These cells, numbering about 2,000 in the eye, send electrical messages to the brain, which constricts the pupil and gives the brain information about circadian rhythms. They are called intrinsically photosensitive retinal ganglion cells, or ipRGCs. "Compared with rods and cones, they're glacially slow and they don't adjust their sensitivity as completely."
. . Whereas rods and cones rapidly communicate changes in brightness and are responsible for coloring our world, the new class of cells send signals about overall brightness, somewhat like the light meter of a camera, telling the brain when it is night and when it is day.
. . "What's peculiar about these cells is that [unlike the rods and the cones] they are output cells, meaning they communicate directly with the brain", Berson explained. "Rods and cones, on the other hand, communicate only with other retinal cells and have to go through two or three levels before they communicate with the brain."

Jan 10, 06: Fungus-gardening ants have the same problems as human farmers—crop-eating pests. A new study shows that these ants enlist the help of antibiotic-producing bacteria to keep their gardens in order.
. . Panamanian attine ants cultivate large houses covered in fungus, which worker ants garden to provide food for the colony. But parasitic microfungi—of the genus Escovopsis—also have a taste for this food. Infected colonies experience a major falloff in garden growth rate and production of new workers. Under some conditions, the pests can completely overgrow the fungus garden.
. . How ants deal with these parasitic pests was a puzzler until researchers peeled away fuzzy white clumps from the ants' undersides—between the head and first pair of legs—and uncovered tiny cavities. Inside each they found a trove of bacteria that produce antibiotics that are deadly to garden pests. To keep the garden clean, the ants simply rub the bacteria, which they originally acquire from other workers, all over.
. . The ants spend most of the time in the parts of the garden where infections are highest, and since their bodies are covered in bacteria, the fungus and any other pests are in direct contact with the antibiotics, Currie added. This service doesn't come free. Researchers also noticed that the ants use special glands inside the cavities to produce food for the bacteria.
. . The relationship between attine ants, bacteria, fungus, and pests originated some 50 to 65.51 million years ago, and has since been shaped by millions of years of co-evolution. As a result, specific groups of ants are specialized to cultivate specific groups of fungi; specific groups of fungi are hosts to specific groups of pests, and specific bacteria work against specific pests.
. . But this raises a question: Why haven't the parasites evolved resistance to the antibiotics? Many of the bacterial pests harmful to humans have become resistant to antibiotics over time, while apparently this microfungi have not. Determining how the bacteria have continually been able to produce antibiotics that stay a step ahead of the pests is the focus of the researchers' next study.

Jan 4, 06: Some whale species sing in different dialects depending on where they're from, a new study shows. Blue whales off the Pacific Northwest sound different than blue whales in the western Pacific Ocean, and these sound different than those living off Antarctica. And they all sound different than the blue whales living near Chile.
. . The hydrophones were developed to listen for earthquakes. But researchers soon realized that they were picking up the sounds of right whales from 25 miles away, and even farther if the water is shallow and the terrain is even.
. . Researchers also heard the calls of critically endangered North Pacific right whales and sperm whales in the Gulf of Alaska. Many of the sperm whales were detected during the winter—nearly twice as many as in the summer --indicating a surprisingly active "off-season" population that scientists had never known.

Jan 6, 06: Modern cats have their roots in Asia 11 million years ago, according to a DNA study of wild and domestic cats. The ancient ancestors of the 37 species alive today migrated across the globe, eventually settling in all continents except Antarctica.
. . Eight major lineages emerged, including lions, ocelots and domestic cats. The moggy [?] is most closely related to the African and European wild cat and the Chinese desert cat.
. . In a relatively small number of migrations, cats spread across the world, as land bridges sprang up between continents. It turns out that the domestic cat is most closely related to the wild cats of Africa, Europe and China.
. . The few discovered cat fossils are very difficult to tell apart. The international team took a different approach by sampling DNA from living cats. They looked at both mitochondrial DNA.
. . The Panthera lineage, which includes the lion, jaguar, cloud leopard and tiger, emerged first. This was followed rapidly by a group of three Asian species - the bay cat, Asian golden cat and marbled cat, three African Species (caracal, African golden cat and serval) and the path that led to the New World ocelot. More recently, four further lines branched off --the pathways to the lynx, puma, leopard cat and domestic cat.

Jan 1, 06: At the University of Colorado, behavioral geneticist John DeFries selectively bred dozens of generations of mice until he had a dark-haired strain that was 30 times as brave as an albino one, as measured by fearfulness tests. The gene variants governing mouse anxiety may turn out to be different than the human ones, but DeFries’s discoveries will probably shed light on genetic contributions to human fear -—and may lead to new drug targets.
. . Social critic Francis Fukuyama, author of Our Posthuman Future, presents a disquieting vision of a pharma-enhanced population. “Stolid people can become vivacious; introspective ones extroverted; you can adopt one personality on Wednesday and another for the weekend", he writes. Fukuyama worries that the qualities that make us essentially human would be lost.

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