I happened to think (2003): There seems to be an evolutionary advantage to shorter individual lives: faster evolution to keep in step with changing environments.
. . The technique of shredding those "aglets" --the ends of our chromosomes-- to achieve a programmed end of individual life must not've been an easy thing, and
would've taken time. So, *before that, did the first (one
or few-celled) organisms have "immortality"? Then, like mammals out-competed marsupials, did the short-life species win? Did the survivability of the species out-weigh the survivability of the individual? Did death "out-compete" immortality?!
See a file on Space.com on the evol of sex. e.g.: "You can imagine a path that leads from the uncorrelated exchange of genetic material to the
completely orchestrated recombination process", he says,
referring to the birth of sex. The bad news, if you're looking for titilation... we're talkin' singles here, but single-celled organisms!
Another on 'tisimal impacts' influence.
. . And: Cold periods are suspected of forcing migrations that created small, isolated groups that could have evolved significantly but then died out. One such period may have occurred as recently as 71,000 years ago.
. . An early-2001 study led by Jeremy Marlow of Newcastle University, showed evidence of a significant cooling of the climate 2 million years ago. Larger impacts could lead to
global warming due to the greenhouse effect (water and CO2), loss of the ozone layer (particularly with ocean impacts that propel chlorine from the NaCl --salt-- into the upper atmosphere), acid rain and toxins.
Chimpanzees and people share about 98.7 % of their DNA, & shared a common ancestor 5 to 7 million years ago. Well, maybe 6-8. / Humans differ among ourselves... only a
percent or so, at most. Chimps differ among themselves 5-6 times that. This shows that at some time in our history, there was a very small number of us. We share half our DNA with a Banana Tree!
It's calculated that it takes only 20,000 years to evolve from black skin to white, as populations emigrated north --& needed more vitamin D creation & less cancer protection.
Artiodactyls: ancestors to modern deer, cows and sheep;
. . Perissodactyls: ancestors to such as horses, rhinos and tapirs. Weasels & dogs evolved apart 30 million years ago. Weasels includes Otters, Fishers, Martins.
Parallel or Convergent evolution --the emergence of chance look-alikes-- involves an evolutionary pattern in which completely unrelated species share similar traits because each has independently adapted to similar ecological and environmental conditions. The marsupial "wolf" (extinct 1937) & marsupial "tiger" (prehistoric) are so called for that reason.
. . This is a magnitude further than mere surface copying --as a moth's wing-coloration to match changing tree-bark. I saw a chipmunk with many stripes rumming down his back (begging for picnic scraps). The way he did a "Groucho-walk" struck me. He kept so low, his belly musta brushed the ground --and he made a wavy path. That & the stripes put me in mind of a snake. Exactly! Predators might think that too, & give him another second or two to escape. He'd have more offspring than unstriped cousins, etc --just like Quagga/Zebra.
Sheep & goats, yes. But were cattle an early offshoot of antelope? Are they that far from Eland, eg, in their morphology?
Estimates show about 12,000 blue whales worldwide. Blue whales in the Pacific can reach 85 feet long vs 100 feet long in the Antarctic. They eat about four tons of krill per day. Blue whales were hunted commercially between 1860s and the 1960s, with an estimated 350,000 killed during that period. They have been protected since 1965.
There's an estimated 300 Right Whales left in the world.
My letter to the local newspaper Editor, 2002
DON'T DISCOUNT EVOLUTION AS "JUST" A THEORY
. . It seems all 12 people who still fight evolution have written in. No flat-earthers yet.
. . Their least-ridiculous mistake is to say that something is "only" a theory. A theory is about as proven as the scientific method lets a concept get. It's what most people would call a law. Such as: we don't have a good theory of gravity yet, but people call it a law.
. . The progression is: idea, conjecture, hypothesis, theory, law. There's a tremendous amount of debate, publication, and experiment between each, sometimes decades long.
. . An idea can be a bad one --one that should be rejected immediately: something I call a "wanna-be-true belief". This is regretable. How poor a belief system... when you convince yourself that something is true... because you want it to be true!
. . If the idea passes tests of logic, it can be boiled down into a specific statement of hypothesis. A scientist then invites conjecture among collegues --the idea evolving as the process goes along --perhaps to formal publication, by then including examples of experiments.
. . The mystic types confuse this: to be unquestioning, as they
often are, is not the same as being open-minded! Quite the contrary.
They have no idea how far one must go in that questioning.
The scientist is the one who experiments, studies, re-experiments, confers, re-experiments, publishes, hears the peer-review, re-experiments, reads of how his collegues have repeated his experiments, improves his technique for his next
experiment, etcetera, etcetera. And he/she should never say that they "know".
And he/she takes both sides; that is the method. The way an experiment is done is to try to "disprove the null hypothesis". In other words, the attempt is to disprove what his own hypothesis is. If he fails, his idea was --probably-- correct. If, however, he succeeds in disproving it, and the work of others also succeeds, then the idea is thrown out.
. . In fact, all experiments try (hard) to prove the null hypothesis: that their idea is wrong. If that fails, they're on to something. S/he better really try to prove themself wrong, because if their result says they're correct, & everybody else's experiments turn out the other way, their career is in trouble!
. . Even "laws" are tentative. This is how science avoids mere belief, and small egos that try to prove what they want to be true. A good experiment lets reality speak, not the scientist. It's part of reality that things change, evolve. You can't start with mere belief, and forever carefully avoid the answers that would blow your belief apart.
. . Increasing the strength of your convictions, in the face of disproof, does not improve the validity or quality of them --it only increases their foolishness.
. . The essence of wisdom --and of the Scientific Method-- is to maintain suspicion about what you want to be true.
. . Jon K. Hart
When we find out about how intelligent other species actually are... it's much like Mark Twain's story about the kid who went off to college, and when he came back, was surprised at how wise and smart his Dad had become!
The emergence of separate races happened relatively recently --by some estimates, between 100,000 and 200,000 years ago.
A finding of chaos theory is that the more complex a system is, the more stable it is.
Skip down to "EVO-NEWS".
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EVOLUTION NEWS, 2008
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Jan 1, 08: In preparation for Charles Darwin's upcoming 200th birthday, the editors of Nature compiled a selection of especially elegant and enlightening examples of evolution.
. . I'd like to suggest another way of looking at the findings below, which range from the moray eel's remarkable second jaw to the unexpected plumage of dinosaurs. They are, quite simply, wondrous — glimpses through an evolutionary frame of life's incredible narrative, expanding to fill every possible nook and cranny of Earth's biosphere. After all, it's hard to stir passion about the scientific validity of evolution without first captivating minds and imaginations.
. . Almost, But Not Quite, a Whale. The fossil record suggests that whales evolved on land, and intermediate species have been identified. But what of their last terrestrial ancestor? In 2007, researchers showed that Indohyus — a 50 million-year-old, dog-sized member of the extinct raoellidae ungulate family — had ears, teeth and bones that resembled whales, not other raoellids.
. . An even more extraordinary transition was made by the first creature to venture onto land —-and that was made possible by Tiktaalik, discovered in 2004 on Ellesmere Island. Tiktaalik had a flexible neck and limb-like fins suitable for shallow waters, and, before long, land.
. . Dinosaurs of a Feather. Archaeopteryx, found in 1861, was long thought to be the first bird. Then it was recognized as something closer to a dinosaur with feathers — but still unique for that. In the 1980's, however, paleontologists digging in deposits more than 65 million years old in northern China found feathered dinosaurs which very definitely did not fly. Some dinosaurs, it appeared, may have looked far different from our traditional conception — and feathers may first have served an insulating or aesthetic, rather than aerodynamic, purpose.
. . The Beginnings of Bones. Neural crest cells originate in the spinal cord before diffusing through our developing bodies, forming face and neck bones as well as sense organs and skin. The fossil record, nearly bereft of embryos, provides little direct insight into these critically important stages. But technologies that let researchers track cells during embryo development finally allowed them to watch the neural crest's development, culminating in the attachment of head to the body at its front, while the back attachment springs from the mesoderm tissue layer. With that established, scientists can decipher shared evolutionary histories from muscle attachments: the cleithrum, for example, a bony girdle found in fishes, lives on in humans as the shoulder blade.
. . Natural Selection in Speciation. That differing selection pressures will cleave one species into two is a simple principle expressed in complex ways. One of these is reproductive isolation —-when, for example, one species of stickleback fish live in freshwater streams, and the other goes to sea. Scientists found that stream-bound sticklebacks prefer larger mates, and genetic analysis confirmed that their populations are indeed diverging.
. . Lizard Games. Take an island in the Bahamas, add a predatory lizard called Leiocephalus carinatus, and the results are immediate. Males among the lizard's favorite prey, Anolis sagrei, soon became longer-legged, so as to better flee after drawing predatory attention during mating displays. In contrast, more sedentary females became larger, making them harder to ingest — a neat display of sex-specific selection pressures.
. . An Evolutionary Arms Race, Frozen in Time. Predator and prey evolve together; the adaptations of one driving adaptations in the other. But how can one study this over time, in detail? Biologists from Belgium's Catholic U of Leuven used water fleas and parasitic mites that had been preserved in the mud of a lake's bottom. The sediments were precisely dated and their inhabitants revived, allowing researchers to mix species from different eras and directly measure their developing capacity for infection and escape.
. . Gene Flow, With Purpose. If dispersed by random animal migration, genes flowing across a region ought to dilute local pockets of genetic adaptation. But migration isn't as random as it seems: As seen in a population of great tits (the bird!) tracked in Oxfordshire, England since 1970, genes flow along channels of opportunity. Individual birds picking nesting spots best-suited to their particular traits, producing local adaptations in tiny parts of the same small forest. (These birds, incidentally, belonged to the same population that have shifted breeding times to match a changing climate.)
. . Selection Finds Its Own Level. Since natural selection favors traits that increase fitness, it seems that populations should eventually become genetically homogeneous. But evolution isn't so one-dimensional: When researchers adjusted the color frequencies of wild guppy populations in Trinidad, they found that unusual variants — regardless of color — had higher survival rates. This is called frequency-dependent survival: selection favoring the rare and disfavoring the common, preventing a long-term homogeneity that —-no matter how beneficial in the short term-— might someday prove disastrous.
. . Making Do. Though so often elegant, evolution can also be jury-rigged and provisional. Witness the Moray eel, whose body is so long and narrow that —-unlike other fish-— the suction created when it opens its mouth is too weak to catch prey. The solution: a second set of jaws and teeth that sprout from the skeleton around its gills. It's not pretty, but it works.
. . The Genes of the Finches. The Galapagos finches whose beak adaptations were described by Darwin —-and later tracked, over decades, by Peter and Rosemary Grant-— are poster animals for evolution. In 2006, researchers found a genetic unit underlying their oft-described progress: calmodulin, whose expression during embryonic development changes beak shape.
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Dec 30, 08: Sharks have wimpy bites for their size and can crunch through their prey only because they have very sharp teeth --and because they can grow to be so big, researchers reported.
Dec 30, 08: The facial expressions we make to show or hide our emotions are hardwired into our brains rather than learned during life, a study has concluded.
. . Blind and sighted athletes made the same expressions when they won and lost. This meant the expressions were not picked up by watching others. The researchers believe they could be remnants of evolutionary history.
Dec 30, 08: Visiting —-or even just viewing photos of family members-— prompts brain activity that affects how you feel about them, your friends, and even yourself, a new study suggests.
. . The study is the first to compare brain activity associated with seeing relatives with that linked to seeing friends and strangers. It suggests our feelings about biological relatives are at least somewhat primal. The findings may help explain everything from why our family can get on our nerves to why people who look like us can spark immediate feelings of trust, "but not lust".
. . "We like to be around people that look more like us, but we do not find them as sexually attractive", added Platek, editor-in-chief of the journal Frontiers in Evolutionary Neuroscience. "I think it is linked to our subconscious ability to detect facial resemblances so we avoid lusting after those that may be related to us."
. . The scientists found that relatives and self-lookalikes are processed through a self-referential part of the brain. Friends and strangers who look nothing like the viewer, on the other hand, light up entirely different areas of the brain, those linked to making important and risky decisions with respect to the self.
. . Platek and Kemp also found that the brain ranks everyone socially, with relatives at the head of the line.
. . Since relatives are processed through areas of the brain linked to self-reference, the study could also help to explain why relatives cause us to take things personally. While we may tolerate a friend's loud laughter or snoring, for example, we may have less patience with a relative because we judge them similarly to how we judge ourselves.
Dec 24, 08: Orangutans can help each other get food by trading tokens, scientists have discovered --but only if the help goes in both directions.
. . Researchers from the U of St Andrews found orangutans could learn the value of tokens and trade them, helping each other win bananas. it is the first evidence of "calculated reciprocity" in non-human primates. Gorillas and chimpanzees were much less willing to co-operate, they report.
. . Initially, Dok, the female, was especially good at swapping tokens to get bananas for Bim, the male. Sometimes Bim would point at the tokens to encourage her. But he was less interested in trading tokens that would win bananas for her.
. . As she became less willing to help him out, Bim responded by trading more and more, until their efforts were more or less equal. "So we have a calculation behind the giving."
Dec 24, 08: The species once described as the world's oldest spider is a more primitive version of the web-spinning modern spider, scientists have found. The parts of the Attercopus spider's described as spinnerets --the appendages that allow web-spinning-- were not spinnerets after all. That means that the oldest "true" spider may have arrived 80m years later than previously thought.
. . The finding prompted the team to return to their original samples, which on further study showed that the spinnerets they had earlier identified were in fact rolled-up pieces of cuticle, the animals' external skeletal material. It seems that Attercopus is a missing link, capable of producing silk but not of weaving it.
. . The oldest "true spider", like the ones seen today, dates from the late Carboniferous period that ended about 300m years ago, though Professor Selden says that true spiders may have existed earlier but have not yet been discovered.
. . "The puzzle about silk was this: we knew that it wasn't used for making webs initially, for catching insects, because there were no flying insects when the earliest spiders were around", Professor Selden said.
. . "Here we clearly have a spider-like animal that could produce silk but didn't yet have these flexible spinnerets for weaving it into webs; we think that this sort of spider would leave a trail of silk as it moved along, using it to find its way back to its burrow."
Dec 23, 08: Bees help plants in more ways than one, scientists find; as well pollination, they help scare caterpillars away.
Dec 19, 08: Call it dino daddy day care. Scientists who examined the fossilized remains of three types of medium-sized dinosaurs found with large clutches of eggs have concluded that the males rather than the females seem to have guarded the nests and brooded the eggs.
. . They said this behavior is seen in certain existing species of birds. Scientists believe birds evolved from small, feathered predatory dinosaurs more than 150 million years ago.
. . The three types of dinosaurs, Troodon, Oviraptor and Citipati, lived roughly 75 million years ago and were theropods --the primarily meat-eating group that also includes monstrous beasts like Tyrannosaurus rex and Giganotosaurus.
. . The males may have mated with several females that laid eggs in one large clutch. When the females left, the males incubated and protected the eggs on their own. In these cases, the dinosaurs were found with an unusually large number of eggs --each nest containing from 22 to 30 eggs. There was no evidence of medullary bone --the extra bone that breeding female birds and dinosaurs use to make eggs.
. . Males contribute to parental care in less than 5% of mammal and reptile species. Males and females contribute to parental care together in more than 90% of birds. Male-only care for eggs occurs among certain large flightless birds like emus and rheas and the South American tinamous.
Dec 17, 08: An unusual raptor dinosaur found in Argentina is the largest of its kind found so far in the Southern Hemisphere, with awkwardly short arms that made it resemble a Tyrannosaurus, researchers reported.
. . The creature would have weighed 368 kg (800 pounds) and been nearly 5 meters long when it hunted in what is now Patagonia 100 million to 65 million years ago. the group would have included animals ranging from crow-sized winged creatures to giants such as A. cabazai.
Dec 15, 08: The tiny tangled threads of the world's oldest spider web have been found encased in a prehistoric piece of amber, a British scientist said.
Dec 15, 08: The bizarre teeth of male beaked whales have evolved to help females choose their mates, research suggests. The males do not seem to use the two teeth on the outside of their jaws for eating, but for scratching each other.
. . Scientists have now used DNA analysis to show the teeth probably evolved as secondary sexual traits to help females select males of the right species.
. . Beaked whales are a family of about 21 species that make up the least known group of whales or dolphins. The shape of the teeth, or tusks, varies markedly between different species. In some, they actually appear to hinder feeding, as they wrap over the upper jaw, preventing it from opening fully.
. . Females do not show teeth; and this difference between the sexes, or sexual dimorphism, is virtually the only way to tell them apart. "It turns out that tusks are largely an ornamental trait that became a driver in species separation."
. . The researchers believe this is the first time that secondary sexual selection has been shown to have shaped the evolution of any marine mammal. Well-studied secondary sexual characteristics include the antlers of deer.
Dec 9, 08: Scientists in Austria say they have found a basic form of jealousy in dogs. The Vienna-based researchers showed that dogs will stop doing a simple task when not rewarded if another dog, which continues to be rewarded, is present.
. . Yhis shows a sensitivity in dogs that was only previously found in primates. The researchers now plan to extend their experiments to look at co-operative behavior in wolves.
. . To make sure that the experiment was really showing the interaction between the dogs rather than just the frustration of not being rewarded, a similar experiment was conducted where the dogs performed the task without the partner. Here they continued to present the paw for much longer.
. . The dogs never rejected the food, something that primates had done when they thought the reward was unfair. The dogs, the researchers said, "were not willing to pay a cost by rejecting unfair offers."
Chileans have a new hero: an apparently homeless dog who's gone missing. A surveillance camera on a Santiago freeway captured images of a dog trotting past speeding cars to pull the body of another dog, mortally struck by a vehicle, away from traffic, to the median strip.
. . The scene was broadcast by Chilean television stations and then posted on Web sites such as YouTube.com, and hundreds of thousands of people had viewed versions of it.
Dec 9, 08: Men of higher intelligence tend to produce better quality sperm, UK research suggests. The latest study tested the gene theory by taking two characteristics that seemed unlikely to be associated with each other --intelligence and sperm quality.
. . A team from the Institute of Psychiatry analysed data from former US soldiers who served during the Vietnam war era. They found that those who performed better on intelligence tests tended to have more --and more mobile-- sperm.
. . The study appears to support the idea that genes underlying intelligence may have other biological effects too. Therefore, if tiny mutations impair intelligence, they might also harm other characteristics, such as sperm quality. Conversely, people with robust genes might be blessed with a biological "fitness factor" making them fit, healthy and smart.
. . But brighter people may be less likely to smoke, and more likely to take exercise, both of which are known to impact on mental performance. They found a small, but statistically significant link, and were able to show that this could not be explained by unhealthy habits, such as smoking or drinking alcohol.
Dec 3, 08: A new fossil species of flying reptile --a type of pterosaur, is the largest of its kind ever to have been discovered. It would have flown in the skies above Brazil 115 million years ago. The pterosaur had a wingspan of 5m and would have been more than 1m tall at the shoulder.
. . The partial skull fossil, found in Brazil, is the first example of a chaoyangopteridae, a group of toothless pterosaurs, to be found outside China.
Dec 2, 08: U.S. researchers say they have discovered what appears to be the oldest imprint of a prehistoric insect, made while the dragonfly-like creature was still alive. It was something related, maybe a mayfly.
. . The imprint was made by an insect about three inches long as it stood on mud some 312 million years ago. The imprint of the insect shows the thorax and abdomen, along with six legs.
Nov 26, 08: Researchers in China have unearthed fossils of the most primitive turtle to date, a creature with teeth, a fully formed belly shell and a back shell that appeared to be just evolving. The Odontochelys lived about 220 million years ago and their discovery sheds light on one of the biggest mysteries in reptile evolution --how the shell and body of the turtle developed.
. . Li said it was clear the turtle first developed the plastron, or the lower shell that encases the belly, before getting its upper shell, or the carapace.
. . They were meat eaters. "They were aquatic animals but we cannot be certain if they were freshwater or saltwater."
Nov 24, 08: The full genome of the Neandertal, an ancient human species probably driven to extinction by the first modern humans that entered Europe some 45,000 years ago, is expected to be recovered shortly. If the mammoth can be resurrected, the same would be technically possible for Neandertals. In fact, Wade points out, there are good reasons to recreate a Neandertal: "No one knows if Neandertals could speak. A living one would answer that question and many others."
. . Whoa there, says Richard Doerflinger of the U.S. Conference of Catholic Bishops: "Catholic teaching opposes all human cloning.
. . George Church, a leading geneticist, suggests (in Wade's paraphrase) that scientists could "modify not a human genome but that of the chimpanzee", bringing it "close enough to that of Neandertals, [with] the embryo brought to term in a chimpanzee." If it's OK to clone a macaque and a chimp, it's pretty hard to explain why, at that last fork in the road, you're forbidden to clone a Neandertal.
Nov 21, 08: A single-celled ball about the size of a grape may provide an explanation for one of the mysteries of fossil history. Researchers say the creature leaves tracks on the seabed which mirror fossilised tracks left up to 1.8 billion years ago.
. . Many palaeontologists believe only multi-celled organisms could have made these tracks. This has been difficult to confirm as no multi-cellular fossils of such an age have ever been found.
. . The discovery was made by marine biologists monitoring the sea bed in the Bahamas. They noticed a great deal of tracks made by grape-shaped creatures called protists. "We were looking for pretty animals that have eyes, are coloured, or glow in the dark; instead, the most interesting find was the organism that was blind, brainless, and completely covered in mud."
. . The 3cm-wide, single-celled protists propel themselves using tiny protruding legs called pseudopodia. A number of openings all over the body act as mouths and outlets for waste. The protists move very slowly, taking weeks or even months to make a track of a few cm.
Nov 19, 08: Researchers have sequenced the gene map of a long-extinct, mummified woolly mammoth, using DNA taken from its hair. The sequence shows that mammoths were more closely related to modern, living elephants than previously thought, and they found some elements, such as evidence of inbreeding, that may shed light on why the giant creatures went extinct. And it shows that it is possible to reconstruct the genomes of extinct creatures.
. . The sequence shows that mammoths, which died out around 10,000 years ago, evolved slowly. "We discovered that individual woolly mammoths were so genetically similar to one another that they may have been especially susceptible to being wiped out by a disease, by a change in the climate, or by humans. Our data suggest that mammoths and modern-day elephants separated around six million years ago, about the same time that humans and chimpanzees separated."
. . Mammoths and elephants appear more closely related than humans and chimpanzees are. Next in line --perhaps Neandertals.
Nov 19, 08: The earliest turtles known to live in water have been discovered on a Scottish island. 164 million-year-old. The new species forms a missing link between ancient terrestrial turtles and their modern, aquatic descendants.
Nov 21, 08: Spiders flying as an educational project aboard the International Space Station seem to have gotten the hang of weightlessness. Their first orbital webs were messy, disorganized affairs. But a week into their flight, television images beamed back to Earth showed surprising progress.
Nov 18, 08: A pair of orb weaver spiders flying aboard the International Space Station have fought a battle with weightlessness and lost.
. . When astronauts took a peek at the spiders' webs, they found a tangled concoction that was a far cry from the elegant symmetrical, creations of their eight-legged brethren on Earth. "The web was more or less three-dimensional and it looked like it was all over the inside of the spider hab." There was no symmetry.
Nov 18, 08: Learning the name of a color changes the part of the brain that handles color perception.
Nov 18, 08: Palaeontologists have pieced together the fossilised skull of the oldest example yet found of a woolly rhinoceros in Europe. The 460,000-year-old skull, which was found in Germany, had to be reconstructed from 53 fragments. The extinct mammals reached a length of three-and-a-half meters in adulthood and, unlike their modern relatives, were covered in shaggy hair.
. . "This is the oldest woolly rhinoceros found in Europe." For more than one hundred years, no one ventured to put the pieces together.
. . Woolly rhino (Coelodonta) first appeared about 2.5 million years ago in the northern foothills of the Himalayas. The animals probably migrated from Asia into East and Central Europe when cold, arid conditions held sway between 478,000 and 424,000 years ago.
. . Their territorial advances were paralleled by changes in anatomy. "It carried its head low along the ground and had a lawnmower-like mouth with a huge set of grinding teeth."
Nov 18, 08: Australia's kangaroos are genetically similar to humans and may have first evolved in China, Australian researchers said. Scientists said they had for the first time mapped the genetic code of the Australian marsupials and found much of it was similar to the genome for humans.
. . Humans and kangaroos last shared an ancestor at least 150 million years ago, the researchers found, while mice and humans diverged from one another only 70 million years ago. Kangaroos first evolved in China, but migrated across the Americas to Australia and Antarctica, they said. "Kangaroos are hugely informative about what we were like 150 million years ago."
Nov 16, 08: Evolution isn’t just for living organisms. Scientists at the Carnegie Institution have found that the mineral kingdom co-evolved with life, and that up to two thirds of the more than 4,000 known types of minerals on Earth can be directly or indirectly linked to biological activity. The finding, published in American Mineralogist, could aid scientists in the search for life on other planets.
. . “Mineral evolution is obviously different from Darwinian evolution —-minerals don’t mutate, reproduce or compete like living organisms. But we found both the variety and relative abundances of minerals have changed dramatically over more than 4.5 billion years of Earth’s history.”
. . All the chemical elements were present from the start in the Solar Systems’ primordial dust, but they formed comparatively few minerals. Only after large bodies such as the Sun and planets congealed did there exist the extremes of temperature and pressure required to forge a large diversity of mineral species. Many elements were also too dispersed in the original dust clouds to be able to solidify into mineral crystals.
. . As the Solar System took shape through “gravitational clumping” of small, undifferentiated bodies —-fragments of which are found today in the form of meteorites-— about 60 different minerals made their appearance. Larger, planet-sized bodies, especially those with volcanic activity and bearing significant amounts of water, could have given rise to several hundred new mineral species. Mars and Venus, which Hazen and coworkers estimate to have at least 500 different mineral species in their surface rocks, appear to have reached this stage in their mineral evolution.
. . Unique to Earth, plate tectonics created new kinds of physical and chemical environments where minerals could form, and thereby boosted mineral diversity to more than a thousand types.
. . What ultimately had the biggest impact on mineral evolution, however, was the origin of life, approximately 4 billion years ago. “Of the approximately 4,300 known mineral species on Earth, perhaps two thirds of them are biologically mediated,” says Hazen. “This is principally a consequence of our oxygen-rich atmosphere, which is a product of photosynthesis by microscopic algae.” Many important minerals are oxidized weathering products, including ores of iron, copper and many other metals.
. . Microorganisms and plants also accelerated the production of diverse clay minerals. In the oceans, the evolution of organisms with shells and mineralized skeletons generated thick layered deposits of minerals such as calcite, which would be rare on a lifeless planet.
. . “One implication of this finding is that remote observations of the mineralogy of other moons and planets may provide crucial evidence for biological influences beyond Earth.”
Nov 13, 08: Canadian researchers say they've narrowed down the likely owner of a dinosaur nest, abandoned on a river's edge 77 million years ago, adding the discovery offers a unique look at dinosaur reproduction and the evolution of birds.
. . Scientists say the nest unearthed in northern Montana in the 1990s likely belonged to one of two types of small, carnivorous dinosaurs. The two suspects are a ceanagnathid, which looks somewhat like an ostrich, or a small raptor called a dromaeosaurid. Both are small by dinosaur standards and related to modern birds. The nest likely held up to a dozen eggs, of which only fossilized fragments remain.
Nov 13, 08: The fossil of a wide-hipped Homo erectus found in Ethiopia suggests females of the pre-human species swayed their hips as they walked and gave birth to relatively developed babies with big heads, researchers said.
. . The size and shape of the 1.2 million-year-old pelvis indicates that H. erectus females had hips wider than those of modern human females and their infants were born with heads about 30% larger than previously calculated.
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. . Homo erectus, Latin for "upright man", arose in Africa 1.8 to 2 million years ago, migrating to Asia and Europe before becoming extinct about half a million years ago. Experts agree it was likely a direct ancestor of modern humans.
Nov 12, 08: Songbirds learn to sing from a recording in their head, according to a new study. The research could also shed light on how humans learn to speak.
. . Swiss researchers have identified a region of the Zebra Finch brain which they believe has an internal recording of how the birds ought to be singing. A separate region seems to enable the birds to identify mistakes in their songs, they wrote.
Nov 12, 08: Despite years of research, the world's scientists have yet to get anywhere near the gold standard --the dragline silk of an orb-weaving spider. Five times tougher than steel. Three times more elastic than Kevlar. It is potentially bulletproof. But you can't make it in factories.
. . Arachnids produce around seven different types of silk --each with different protein structures and mechanical properties, optimized for different tasks.
. . They weave their threads from a liquid known as "dope", stored as gel inside the spinning glands. The gel is a mixture of water-soluble proteins, which behave under flow like molten polymers. When this solution is pulled through the spider's spinning glands, it turns into a solid fiber. The Oxford scientists know the ingredients of the dope. They know the balance of these molecules. And they even know the structure of the spinning glands.
. . "We have been eagerly awaiting Isis 2, because it is targeted at biosciences", she explains. "First of all, it will have a higher flux of neutrons - around 20 to 40 times brighter. And the detectors are better positioned for studying biological materials." All in all, it is the perfect machine for deconstructing the spiders' magic tricks.
Nov 10, 08: Many octopuses evolved from a common ancestor that lived off Antarctica more than 30 million years ago, according to a "Census of Marine Life" that is seeking to map the oceans from microbes to whales.
. . Researchers in 82 nations, whose 10-year study aims to help protect life in the seas, found a mysterious meeting place for white sharks in the eastern Pacific Ocean and algae thriving at -25 degrees C in the Arctic.
. . It has identified 5,300 likely new species, of everything from fish or corals. So far, 110 have been confirmed as new. Among the findings, genetic evidence showed that the tentacles of the octopus family pointed to an Antarctic ancestor for many deep sea species. A modern octopus called adelieledone in Antarctica seemed the closest relative of the original.
. . White sharks traveled thousands of km to spend six months at what researchers called the "White Shark Cafe" in the Pacific between Hawaii and California. "During this time, both males and females make frequent, repetitive dives to depths of 300 meters" it said. Researchers said the purpose was unknown but may be linked to food or reproduction.
. . Among other findings were a predatory comb jelly anchored to the seabed in waters 7,217 meters deep near Japan. "It was found at a depth thought incapable of supporting predators like this one."
. . The discovery of a wealth of new species was not a sign that the oceans were healthier than thought.
Nov 5, 08: Europe's environment chief plans to ban laboratory tests on mankind's closest relatives --chimpanzees, gorillas, bonobos and orangutans-- in a clampdown on animal testing by the drugs industry.
Nov 6, 08: A new comparison of chimpanzee and human genomes has offered an early but tantalizing look into what makes the two species, nearly identical at the DNA level, so different. Scientists found key differences in areas linked to cell differentiation and immune response —-and that could be just the beginning.
. . Researchers already know that humans and chimpanzees share about 98% of the same genes. But rather than searching for mutations, Redon's team looked at a relatively unstudied phenomenon known as copy number variation, or CNV, in which genes are redundantly duplicated. Redon stopped short of saying that CNVs are more important than other types of genetic variation, instead calling them complementary.
Oct 31, 08: A rare reptile with lineage dating back to the dinosaur age has been found nesting on the New Zealand mainland for the first time in about 200 years.
. . Tuatara, dragon-like reptiles that grow to up to 32 inches, are the last descendants of a species that walked the earth with the dinosaurs 225 million years ago, zoologists say. They have unique characteristics, such as two rows of top teeth closing over one row at the bottom. They also have a pronounced parietal eye, a light-sensitive pineal gland on the top of the skull. This white patch of skin –-called its “third eye” –-slowly disappears as they mature. They still live in the wild on 32 small offshore islands cleared of predators.
Oct 30, 08: Sabretooth "tigers" were social animals who lived and hunted in prides, a study suggests.
Oct 28, 08: When it came to the sense of smell among meat-eating dinosaurs, Tyrannosaurus rex nosed out the competition. Scientists compared the size of their olfactory bulbs --the part of the brain regulating the sense of smell-- in a wide range of carnivorous dinosaurs.
. . Other experts have pointed to T. rex's stellar smeller as evidence that it must have been more of a scavenger than an active hunter. Therrien disagreed. "But when we look at modern animals, we see that's not the case. Scavengers don't necessarily have a better sense of smell. You have some like the turkey vultures that have a good sense of smell. But you have other scavengers like the Old World vultures that actually have a typical sense of smell because they use sight instead of smell to locate prey."
. . Archaeopteryx, the earliest known bird with fossils dating to 150 million years ago, turned out to have a good sense of smell in line with that of the small meat-eating dinosaurs from which paleontologists believe birds evolved, they said.
Oct 26, 08: Researchers have discovered that honey bees can count to four.
. . A researcher from the U of Queensland put five markers inside a tunnel and placed nectar in one of them. Honey bees placed in the tunnel flew to the marker with the food, and would still fly to the same marker stripe when the food was removed. "If you train them to the fourth stripe, they will look the fourth stripe and so on. But their ability to count seems to go only up to four. They can't count beyond four.
. . "The more we look at these creatures that have a brain the size of a sesame seed, the more astonished we are. They really have a lot of the capacities that we so-called higher human beings possess."
Oct 26, 08: A smelly rotten-egg gas in farts controls blood pressure in mice, a new study finds.
. . The unpleasant aroma of the gas, called hydrogen sulfide (H2S), can be a little too familiar, as it is expelled by bacteria living in the human colon and eventually makes its way, well, out.
. . The new research found that cells lining mice's blood vessels naturally make the gas and this action can help keep the rodents' blood pressure low by relaxing the blood vessels to prevent hypertension (high blood pressure). This gas is "no doubt" produced in cells lining human blood vessels too, the researchers said.
. . "Now that we know hydrogen sulfide's role in regulating blood pressure, it may be possible to design drug therapies that enhance its formation as an alternative to the current methods of treatment for hypertension."
Hydrogen sulfide is the most recently discovered member of a family of gasotransmitters, small molecules inside our bodies with important physiological functions.
. . This study is the first to reveal that the CSE enzyme that triggers hydrogen sulfide is activated itself in the same way as other enzymes when they trigger their respective gasotransmitter, such as a nitric oxide-forming enzyme that also regulates blood pressure
. . Because gasotransmitters are common in mammals all over the evolutionary tree, these findings on the importance of hydrogen sulfide are thought to have broad applications to human diseases, such as diabetes and neurodegenerative diseases.
Oct 26, 08: A new study shows that humans had the ability to make fire nearly 790,000 years ago, a skill that helped them migrate from Africa to Europe. Researchers now say that ancient man could actually start fire, rather than relying on natural phenomena such as lightning.
. . By analyzing flints at an archaeological site on the bank of the river Jordan, researchers at Israel's Hebrew U discovered that early civilizations had learned to light fires, a turning point that allowed them to venture into unknown lands.
Oct 25, 08: A rare juvenile skull of a 190 million-year-old dinosaur may help explain when an important group of plant eaters branched off from carnivorous cousins, U.S. and British researchers said.
. . The tiny skull belonged to a young Heterodontosaurus. Its tooth structure --sharp canine teeth for biting and tearing and flat grinding teeth-- suggest the tiny creature was evolving from a meat eater to a plant eater. The first dinosaurs appeared about 230 million years ago, and the earliest known ones were meat eaters.
Oct 22, 08: Its four limbs lacked contour feathers for flight and it probably lived from the Middle to Late Jurassic periods, or 176 to 146 million years ago. This means it is older than the Archaeopteryx, which lived around 155 to 150 million years ago.
. . Feathered but flightless, the small creature weighed just 164 grams and had buck teeth resembling that of carnivores. But like the Microraptor --which lived in a later period 130 to 125 million years ago-- it gave important evidence about the evolutionary relationship between birds and dinosaurs. "You could say it was a link between dinosaur and birds. It was very close to the ancestor of birds."
Oct 22, 08: Archaeologists in China have discovered fossils of a pigeon-sized feathered dinosaur which they believe to be an ancestor of birds. Its remains were found 90% complete, preserved in a slab of rock.
Oct 22, 08: Female spiders who eat would-be suitors produce more babies, and those babies are stronger and bigger, than spiders who stick to more mundane fare, researchers reported.
Oct 20, 08: Scientists have identified an amazing collection of dinosaur footprints on the Arizona-Utah border in the US. There are so many prints --more than 1,000-- that geologists have dubbed the site "a dinosaur dance floor".
. . The marks were long thought simply to be potholes gouged out of the rock by years of erosion. At least four dinosaur species were present, with the animals ranging from adults to youngsters. "The different size tracks [2.5 - 50cm] may tell us that we are seeing mothers walking around with babies."
Oct 17, 08: Originally considered a dud, an old volcano-in-a-bottle experiment designed to mimic conditions that may have brewed the components of life might have been right on target. After reanalyzing the results of unpublished research conducted by Stanley Miller in 1953, chemists realized that his experiment had actually produced a wealth of amino acids —-the protein foundation of life.
. . The latest results, derived from samples found in an old box by one of Miller's former graduate students, come from a device that mimicked volcanic conditions now believed to have existed three billion years ago. The findings suggest that amino acids could have formed when lightning struck pools of gas on the flanks of volcanoes.
. . Miller didn't have access to high-performance liquid chromatography, which lets chemists break down and classify samples with once-unthinkable levels of precision. And when Bada's team reanalyzed the disregarded samples, they found no fewer than 22 amino acids, several of which were never seen by Miller in a lifetime of primordial modeling.
. . "The amino acid precursors formed in a plume and concentrated along tidal shores. They settled in the water, underwent further reactions there, and as they washed along the shore, became concentrated and underwent further polymerization events", explained Indiana U biochemist Adam Johnson, a co-author of the study. "And lightning" —-the final catalyst in the equation-— "tends to be extremely common with volcanic eruptions." Today, almost all volcanic eruptions are accompanied by violent electric storms. "What we suggest is that volcanoes belched out gases just like the ones Stanley had used, and were immediately subjected to intense volcanic lightning. Material could then have been washed down the flanks of volcanoes into pools or coastal bays.
. . Miller, using the old methods, had found five amino acids; Jeffrey Bada and his teams tracked down 22. What is more, the overall chemical yields were often higher than in the first set of experiments --the mixture appeared to be more fertile.
Oct 17, 08: A stick bug from the island of Borneo measuring well over a foot in length has been identified by researchers as the world's longest insect.
Oct 16, 08: Dr. Daiki Horikawa from NASA Ames Research Center has been examining strange creatures called tardigrades for the last seven years. He explains, "tardigrades are small invertebrate animals, 0.1 to 1.0 mm in body length, that live in terrestrial mosses, soil, or lichens. They also inhabit ocean and polar regions." Often known by their nickname, "water bears", studies of these bizarre creatures have surprised scientists.
. . Recent research has shown that water bears can survive the dangerous conditions of space. Previously, the only organisms that have been exposed to the radiation and vacuum of space and lived to tell the tale are certain types of bacteria and lichen. That simple animals like tardigrades also can survive gives more credence to the theory of panspermia, which claims that organisms could move from world to world after travelling though space.
. . They were heated up to sizzling temperatures of 194 F (90 C). Then a group was frozen at -321 F (-196 C). The next batch was given a dose of radiation similar to what they would receive in space — around 4,000 times stronger than that which would make humans ill. The last selection was covered in a dissolving chemical (99.8% acetonitrile, a chemical which may be present in Titan's atmosphere).
. . The results, published in a recent issue of the journal Astrobiology, were that water bears in their suspended animation state survived everything that was thrown at them.
Oct 15, 08: An extraordinary fish that existed 375 million years ago had unique features in its head that helped pave the way for vertebrate animals to live on land, scientists said. The so-called "walking fish" discovered in the Canadian Arctic in 2004. It is considered an important transitional animal in the evolution of fish into amphibians, the first land-dwelling vertebrates.
. . The findings showed that the migration from water to land was more complicated than merely having a fish's fins transform into legs. The head showed changes from more primitive fish that helped adapt to the new feeding and breathing conditions presented by a terrestrial environment, the scientists said. Like some other fish of its time, it had gills and lungs. Its fins had discernible wrists and elbows in an evolutionary step toward legs that could be used to walk around on dry land.
Oct 16, 08: The ornate headgear worn by duck-billed dinosaurs millions of years ago was used to make eerie, bellowing calls, suggests a new study. The study also showed that as the dinosaurs matured into adults, their voices probably changed from high-pitched to deep.
. . Duck-billed dinosaurs (plant-eaters with long, flattened snouts) called lambeosaurs that sported flashy caps that would have put to shame any "Star Wars" hairdo. The caps enclosed nasal passages that looped through the head crest to form large air chambers before passing into the airway (throat).
. . The result confirms one of the theories, that the head crests were used for vocal communication. The upshot is a picture of lambeosaurs shouting out to one another, wooing mates and warning one another of nearby enemies.
. . And if the study results hold true, when a lambeosaur made calls, air would travel through the nasal passages enclosed by the head crest. Since the sizes and shapes of head crests (and nasal pasasges) differed among lambeosaurs, each one had its own voice - their calls also would have sounded distinctive individual by individual
. . If the lambeosaurs were in fact communicating with one other through vocal calls, the researchers suspected a well-developed brain could be at work to support such sophisticated behaviors. And that's what they found. The reconstructed brains showed relatively large cerebral hemispheres, which are linked with higher thought and problem-solving.
. . As the crests got bigger and the animal matured, the dinosaurs' nasal passages became longer and more convoluted. "The idea is that as these animals grow they would actually be starting to, in a sense, develop the tools and the ornaments to enter into the breeding pool."
Oct 14, 08: No matter whether you're talking elephants or bacteria, a new study proposes that, pound for pound, all living things' at-rest metabolisms use similar amounts of energy. Though living things vary greatly in complexity and size, their energy usage falls between 3 and 90 watts per kilogram of biomass. For comparison, a MacBook Pro is supposed to draw about 12 watts when operating from its battery.
. . That contradicts earlier, highly-influential studies led by James Brown, Brian Enquist and Geoffrey West, of the U of New Mexico, U of Arizona and Los Alamos National Laboratory respectively. They found a strong correlation between the size of an animal and its metabolism. Under their rubric, small creatures used energy efficiently while large creatures did not. As organisms grow larger, they produce less energy relative to their bulk.
Oct 14, 08: "They are a people. Non-human, but definitely persons", said Deborah Fouts, co-director of the Chimpanzee and Human Communication Institute. "They haven't built a rocket ship to Luna. But we're not that different."
. . Fouts is one of a growing number of scientists and ethicists who believe that chimpanzees —-as well as orangutans, bonobos and gorillas, a group colloquially known as great apes-— ought to be considered people.
. . It's a controversial position. If being a person requires being human, then chimpanzees, our closest primate relative, are still only 98% complete. But if personhood is defined more broadly, chimpanzees may well qualify. They have self-awareness, feelings and high-level cognitive powers. Hardly a month seems to pass without researchers finding evidence of behavior thought to belong solely to humans.
. . "They do remember the past. When people come that they haven't seen in many years, they use their name signs", she said. Taglialatela echoed Fouts. "I don't know if they think about what they want to be when they grow up", he said, "but they understand the concept that something will happen later."
. . Chimpanzees even appear capable of altruism, being willing to help strangers in the absence of anticipated reward. And Fouts, who said that chimpanzees "feel pain and anger and love and affection and the kinds of feelings we feel", said that her sign language-trained chimpanzees can indeed inquire about the well-being of their handlers.
Oct 13, 08: Despite their reputation as lovers not fighters of the primate world, bonobos actually hunt and eat other great apes, German researchers said. Their findings, the first direct evidence of hunting by the so-called "hippie" apes, show that such behavior is not linked to male dominance as females rule bonobo society and also go on hunts.
. . Over five years of observing a group of bonobos the researchers recorded about 10 instances when a group of the apes set out on hunting trips in search of chimpanzees.
Oct 9, 08: Babies as young as 5 months can distinguish an upbeat tune, such as "Ode to Joy" from Beethoven's Ninth Symphony, from a lineup of gloomy tunes. The finding is another example of how babies make sense of the world long before they can talk.
Oct 9, 08: Brachiosaurs and other long-necked giants of the dinosaur world weighed as much as 10 African elephants. Researchers now think they know why the tubby vegetarian beasts got so big: They swallowed high-energy foods whole.
. . Their small heads helped, too, by allowing those long necks to reach nutritious leaves high up in the trees. With body lengths of more than 40 m and heights of 17 m, sauropods dwarfed meat-eating dinosaurs and even the largest land mammals ever.
. . Sauropods instead relied on giant bellies for storing lots of food, which could take a long time to digest. Past research has shown that the ferns and other plant material eaten by sauropods packed high amounts of energy needed for growth.
. . While a complex gut region was necessary, sauropods didn't need big jaws since they didn't chew their food. The smaller jaws meant sauropods could have small heads, which was a prerequisite for having a lengthy neck. The neck meant the beasts could snag food that was out of reach for their stumpy-necked neighbors.
. . But life's tough for big guys. For instance, getting rid of excess body heat could have posed a problem for such a big body. And with such a long neck, a large volume of air had to trek through the also-lengthy windpipe before that fresh air reached the lungs.
. . These dinosaurs solved both problems with a bird-like breathing system. Instead of flexible lungs that expand and contract, sauropods (and modern birds) had a system of air sacs that pumped air through rigid lungs. Other air sacs and hollow spaces lined the spinal column and helped to shuttle unwanted heat away from the body core.
Oct 7, 08: The oldest-known tracks of a creature apparently using legs have been discovered in rock dated to 570 million years ago in what was once a shallow sea in Nevada.
. . Scientists think land beasts evolved from ancient creatures that left the sea and evolved lungs and legs. If the new finding is real --the discoverer says will fuel skepticism-- it pushes the advent of walking back 30 million years earlier than any previous solid finding.
. . The aquatic creature left its "footprints" as two parallel rows of small dots, each about 2 millimeters in diameter. Scientists said today that the animal must have stepped lightly onto the soft marine sediment, because its legs only pressed shallow pinpoints
. . The tracks were made during what is called the Ediacaran period, which preceded the Cambrian period, the time when most major groups of animals first evolved. Scientists had once thought only microbes and simple multicellular animals that existed prior to the Cambrian, but that notion is changing.
. . Little can be gleaned about what sort of creature it was, but Babcock "reasonably certain --not 100 percent" that it was an arthropod, such as one resembling a centipede or millipede. It might have been about one as wide as a pencil and may have had multiple, spindly legs.
Oct 1, 08: Some colorful cichlid fish in Africa's Lake Victoria formed a new species by adapting their vision, showing that geographical isolation is not essential for divergence, researchers said. The fish evolved to improve their ability to see food and predators at different depths, and this also affected the way they saw colors and attracted mates.
. . The cichlid fish are an important model for evolutionary biologists because no other group of vertebrates has split into so many species --about 2,000-- so quickly. Scientists also generally believe that originating a new species requires geographical isolation --such as two continents drifting apart. The fact that the two different cichlid fish species live side by side is puzzling.
Sept 30, 08: Scientists have unearthed the remains of a large meat-eating dinosaur with a breathing apparatus much like a modern bird, fortifying the link between birds and dinosaurs and helping to explain the evolution of birds' unique system of breathing.
. . Instead of lungs that expand and contract, Sereno thinks this beast had air sacs that worked like a bellows, blowing air into the beast's stiff lungs, much like modern birds. Its bones have pockets and a sponge-like texture called "pneumatization" in which air sacs from the lung invade the bone.
. . This 10 meter-long, two-legged predator weighed as much as an elephant and likely had feathers. Most paleontologists believe birds evolved from small, feathered meat-eating dinosaurs, and the earliest known birds were strikingly similar to these dinosaurs.
Sept 23, 08: Even in the dinosaur world, the small and dainty existed, in the form of a mini-dino that likely didn't terrorize any creatures other than termites. The newly described dinosaur, called Albertonykus borealis, was about the size of a chicken and is now considered the smallest dinosaur to have existed in North America. "These are bizarre animals. They have long and slender legs, stumpy arms with huge claws and tweezer-like jaws."
. . The researchers also found evidence for termite borings in fossilized wood discovered in the same area where the mini-dino fossils showed up, also supporting the idea that this dinosaur was a termite eater.
Sept 22, 08: The diet of prehistoric Neandertals living in caves on the Rock of Gibraltar included seals and dolphins, showing once again that the hominids had skills rivaling those modern humans living then, according to a new study. The discovery of seal, dolphin and fish remains in the caves dating from 60,000 to 30,000 years ago provides the first evidence that Neandertals ate sea mammals as well as land grub.
. . Archaeologists found the mammals' remains among Neandertal hearth sites in Vanguard and Gorham's Caves on the Rock of Gibraltar. The bones of some of the animals have cut marks that were likely made by Neandertals using flint knives, also found on site, to cut the meat off.
Sept 22, 08: When early humans mastered the use of fire, their immediate rewards were warmth, light, and protection from nocturnal predators.
. . Investigators have assumed that our ancestors also quickly realized the advantages of flame-cooked food --easy chewing and digestion-- though clear evidence has been hard to find. A new study bolsters that idea, showing that we share our fondness for cooked grub with our wild cousins, the great apes.
Sept 18, 08: Marine scientists have discovered hundreds of new animal species on reefs in Australian waters, including brilliant soft corals and tiny crustaceans.
Sept 18, 08: When you have a headache, you take a couple aspirin, but when plants get stressed out, they just make their own. Scientists had known that plants in laboratories produce a chemical called methyl salicylate --a form of the painkiller aspirin-- when stressed out, but they had never detected it in plants out in nature.
. . Scientists think that the methyl salicylate has two functions: stimulating a process similar to the immune response in animals that helps plants resist and recover from disease, and acting as a form of chemical communication to warn neighbors of threats.
Sept 16, 08: Head of education at the Royal Society quits after saying creationism should be discussed in science lessons.
Sept 16, 08: The Vatican said today the theory of evolution was compatible with the Bible but planned no posthumous apology to Charles Darwin for the cold reception it gave him 150 years ago.
Sept 16, 08: German biologists have discovered a new species of ant they believe is the oldest on the planet, dating back around 120 million years. Resembling a miniature wasp, the insect is like no other ant.
Sept 11, 08: Thanks to a big stroke of luck 200 million years ago, dinosaurs beat out a fearsome group of creatures competing for the right to rule the Earth, scientists said.
. . Dinosaurs appeared about 230 million years ago, during the Triassic Period, and competed for 30 million years with a group of reptiles called crurotarsans, cousins of today's crocodiles that grew to huge sizes and looked a lot like dinosaurs. Many scientists believed dinosaurs were simply superior to crurotarsans and fared better because the earliest dinosaurs walked on two legs, not four, and because they may have been warm-blooded.
. . Brusatte concluded, because some type of planetary calamity 200 million years ago --dramatic climate change or maybe a large meteorite impact-- nearly wiped out the crurotarsans while sparing the dinosaurs. The North American phytosaur Smilosuchus grew to 13m long.
. . Others called rauisuchians were land predators with four powerful legs, massive skulls and flesh-tearing teeth. South America's Fasolasuchus grew to 10m long. Both were far more impressive than the typical dinosaur predator of the time like Coelophysis, a relatively lightly built, two-legged hunter about 3m long.
Sept 10, 08: Bat watchers are preparing for a seasonal phenomenon which sees large numbers of the mammals swarm at the entrances to caves and tunnels. The behavior comes at a time when males "sing" to attract a mate.
. . Biologists at the U of Leeds are studying how females pick mates from among masses of males during what was described as "bat discos". "Males are thought to be faithful to a particular site, but the females will go from one 'nightclub' to another. They also spend time chasing off sneaky males trying to sidle up to their harem. A male pipistrelle may attract up to 10 females to a bat box."
Sept 10, 08: Dermestid beetles are well known in forensic circles: They congregate on corpses to feed and breed, and their presence and life stage can help establish when the victim died.
. . Now, new evidence shows that dermestids were recycling carcasses as far back as the Jurassic. After examining 7,000 fossilized bones in addition to the Camptosaurus's, Britt says insect marks are common but often go unnoticed. Insect activity could explain some fossil mysteries, such as "dinosaur dentures" --teeth that are found side by side in perfect order but without any supporting jaw. Chances are, scavenging insects ate the whole bone away before it could fossilize.
Sept 9, 08: A tiny, six-legged critter that can suspend all biological activity in extreme environments survived a journey to space that would have instantly killed any human and most other life forms. In the first test of its kind, researchers exposed the hardy segmented creatures, called "water bears", to the open and harsh vacuum of space, with all its deadly radiation, on a spacecraft in low-Earth orbit. Many of them survived.
Sept 8, 08: Ostriches, emus, kiwis and other winged non-flyers might seem to be birds of a feather, sharing similar evolutionary origins, but the story could turn out to be much weirder with perhaps numerous flying ancestors. This group of birds is called ratites. Many scientists previously figured the ratites, a group that also includes rheas and cassowaries, all shared a common ancestor that was flightless.
. . However, a new analysis shows they do not share this single hypothetical flightless ancestor. Rather they probably evolved from more than one different airborne ancestor. "We think the most likely hypothesis is that the tinamous, rheas, cassowaries, emus, and kiwis had an ancestor that could fly, and that flight was lost at least three times (once in ostriches, once in rheas, and once in the emu-cassowary-kiwi group)."
Sept 4, 08: The largest study of ancient woolly mammoth DNA helps confirm the "out of America" theory.
. . The scientists question the direct role of climate change in the eventual demise of these large beasts. They believe that woolly mammoths survived through the period when the ice sheets were at their maximum, while other Ice Age mammals "crashed out".
Sept 4, 08: Bumblebees learn from their encounters with camouflaged crab spiders and adapt their foraging strategy.
Sept 4, 08: The brain of the tiny C. elegans worm has a mere 302 neurons. It doesn't need any more, because some of those neurons have an exceptional number of interconnectors.
Sept 1, 08: Asian elephants can do mathematics, proving their skill at addition in an experiment with their favourite food, a Japanese researcher said. One elephant was 87% correct and the other 69% right in months of addition exercises involving single digits.
. . In one test, researchers dropped three apples into one bucket and five into another bucket and then added two apples to each. Five times out of six, Ashya, a 30-year-old female elephant at Tokyo's Ueno Zoo, chose the bucket with seven apples rather than five although she could not see or feel the inside of the containers. The two elephants maintained a good showing with larger numbers and slim margins.
Aug 28, 08: Sponges are very primitive animals. They don't have nerves cells (nor muscles nor eyes nor a lot of other things we commonly associate with animals). So scientists figured sponges split from the tree of life before nerves evolved.
. . A new study has surprised researchers, however. "We are pretty confident it was after the sponges split from trunk of the tree of life and sponges went one way and animals developed from the other, that nerves started to form", said Bernie Degnan of the U of Queensland. "What we found in sponges though were the building blocks for nerves, something we never expected to find."
Aug 27, 08: Early stone tools developed by our species Homo sapiens were no more sophisticated than those used by our extinct relatives the Neandertals. The findings cast doubt on suggestions that more advanced stone technologies gave modern humans a competitive edge over the Neandertals.
Aug 26, 08: Animals know how to speak up, pipe down, cut to the chase or spin a long yarn in order to stand out amidst the din when it comes to communicating with peers, a new set of studies suggests. A host of studies that investigate the ways that animals adapt their calls, chirps, barks and whistles to their social situation.
Aug 26, 08: Monkeys can experience the joy of giving in much the same way as humans do, U.S. researchers reported. Tests in capuchin monkeys showed the animals consistently chose to share food with another monkey if given the option, suggesting they are capable of empathy.
. . His team tested eight female brown capuchin monkeys in pairs. They could choose a token that gave only themselves a treat or an option that rewarded both of them, called a prosocial option. Either way, the first monkey got the same amount of food.
. . "Subjects systematically favored the prosocial option provided their partner was a) familiar, b) visible, and c) receiving rewards of equal value", De Waal's team wrote. "Empathy increases in both humans and animals with social closeness, and in our study, closer partners made more prosocial choices."
Aug 25, 08: Grazing cattle and sleeping deer tend to align their bodies along the North-South axis of the Earth's magnetic field, European researchers said on Monday, giving new meaning to the phrase animal magnetism.
Aug 21, 08: An ancient tar pit exposed when Venezuelan oil workers laid a pipeline has yielded a rich trove of fossils, including a type of saber-toothed cat that paleontologists had never found before in South America.
Aug 19, 08: Magpies can recognize themselves in a mirror, highlighting the mental skills of some birds and confounding the notion that self-awareness is the exclusive preserve of humans and a few higher mammals. It had been thought only chimpanzees, dolphins and elephants shared the human ability to recognize their own bodies in a mirror.
. . But German scientists reported that magpies --a species with a brain structure very different from mammals-- could also identify themselves. Prior and his colleagues tested their magpies by marking the birds' bodies with a red or yellow dot that could only be seen in a mirror. They found the birds regularly scratched the mark on their body, proving they recognized the image in the mirror as themselves and not another animal.
. . In particular, it had been thought that the neocortex brain area found in mammals was crucial to self-recognition. Yet birds, which last shared a common ancestor with mammals 300 million years ago, do not have a neocortex, suggesting that higher cognitive skills can develop in other ways.
. . The discovery of self-awareness in magpies follows a 2002 study in which a crow stunned researchers with its tool-making skills, by twisting a wire into a hook to lift food from a tube.
. . Prior believes parrots, too, may yet show hidden mental skills --but it is the crow family, which includes magpies and jays, that is the smartest.
Aug 19, 08: In what is thought to be a world first, a wild dolphin is apparently teaching others to tail-walk.
Aug 18, 08: Four legs are good--but two legs are more energy-efficient, theorizes a researcher at the U of California at Davis. For some, walking on two legs consumes less energy than walking on all fours, according to a paper from UC Davis. The findings may help explain why human ancestors evolved into bipeds 10 million years ago.
. . The study --which compared data from humans and specially trained chimps on treadmills-- found that humans used about 75% less energy and burned 75% fewer calories than walking on all fours or two legs for chimpanzees, according to the report.
. . Interestingly enough, some of the chimps in the experiment --who were taught to walk on two legs and to "knucklewalk"-- also did better on two legs.
Aug 14, 08: In the warm, bubbling pools of Mono Lake in California, scientists have isolated a bacterium that fuels itself on arsenic.
Aug 13, 08: How many legs does an octopus have? The answer should be easy. But not any more. For new research suggests they are not really eight-legged denizens of the deep, as popularly assumed; instead they use their front limbs more like arms -- and can even tackle a Rubik's Cube.
. . Octopuses use their back two limbs largely for propulsion and use the front six for a variety of tasks, with the front two doing most of the exploratory work.
Aug 8, 08: Scientists who sequenced the mitochondrial DNA of a 38,000-year-old Neandertal returned no evidence of ancestral interbreeding with our long-lost cousins. They could do so in part because the mitochondrial genome, housed in cell-powering mitochondria rather than cell nuclei, contains just 37 genes. (The full human genome contains about 25,000 genes.)
Aug 6, 08: Dogs find human yawns contagious, suggesting they have a rudimentary capacity for empathy, British scientists said.
Aug 4, 08: Mosses once grew and insects crawled in what are now barren valleys in Antarctica, according to scientists who have recovered remains of life from that frozen continent. Fourteen million years ago, the now lifeless valleys were tundra, similar to parts of Alaska, Canada and Siberia —cold but able to support life, researchers report.
. . The moss was essentially freeze dried, he said. Unlike fossils, where minerals replace soft materials, the moss tissues were still there. Further study uncovered remains of tiny crustaceans known as ostracodes, small midges and beetles, and pollen from southern beech trees and pink plants. "The existence of wet-based glaciers, proglacial lakes, tundra vegetation and insect remains all indicate that the climate of the western Olympus range ... was warmer and wetter that that of today."
. . For 50 million years, the Earth has been cooling, he said. "As it cools, it crosses thresholds. This is one, when Antarctica became permanently frozen and locked up. You have to understand where these thresholds are", he added, "Because, if human beings are unfortunate enough to push climate over one of these thresholds, it could be a total catastrophe."
Aug 3, 08: Scientists have identified the world's smallest snake -- a reptile about 4 inches long and as thin as spaghetti that was found lurking under a rock on the Caribbean island of Barbados.
Aug 3, 08: Paleontologists digging in a brickyard in southern Poland have discovered the remains of a dinosaur they say is a previously unknown ancestor of the Tyrannosaurus Rex.
Aug 3, 08: Paleontologists digging in a brickyard in southern Poland have discovered the remains of a dinosaur they say is a previously unknown ancestor of the Tyrannosaurus Rex.
July 30, 08: The parasitic dodder vine consumes water and nutrients from a host plant and, scientists have just discovered, it taps into the host's communication system. Plants use RNA molecules to send messages to different parts, say from roots to leaves. In the new study, RNA molecules from a host tomato plant were found in the parasitic dodder vine, up to 30 cm from where the dodder grafted itself to the host.
. . "It might be important for the parasite to know when the host is flowering, so it can flower at the same time", before the host dies. In a 2006 study, baby dodder plants were found to sniff the air for signs of plant victims, then attack. Similarly, a western U.S. shrub called sagebrush has a remarkable ability to chat. When one 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.
. . Earlier this year, a research team found that insects below and above the ground use the mustard plant like a chemical telephone. A bug munching on the roots, for example, could send chemical signals up to the leaves to essentially put out a "no vacancy" sign.
July 28, 08: Tree shrews that thrive on fermented nectar suck up amounts that would inebriate a human but seem to have no such ill-effects themselves, researchers reported. They said their findings may shed light on how animals evolved a taste for alcohol and may help in understanding why so many humans abuse it. "The 3.8% maximum alcohol concentration that we recorded is among the highest ever reported in a natural food."
. . The tree shrew, found in Malaysia, is very similar to the last common ancestor of all living primates --a group that includes people-- and it could be that the human taste for alcohol evolved millions of years ago.
July 28, 08: “If you listen closely, the songs sung by a swamp sparrow from a population in New York sound different from a swamp sparrow in Pennsylvania. ... It could be likened to a dialect, or an accent.” It turns out that these dialects stem from the way that baby birds learn to sing –-a process that is much like the way human babies learn to talk.
. . For most animals, including non-human primates, communicative sounds develop naturally, without the need for tutors. Only select bird species, humans and perhaps some whales incorporate both nature and nurture into vocalizations.
July 22, 08: Deep below the sea floor live massive colonies of primitive microbes. Almost like one-celled zombies, these microbes use so little energy that it might be more accurate to call them undead rather than alive. Yet scientists think that the species might provide a model for life on other planets. Even on this planet, such microbes might account for a whopping 10% of the Earth's biomass.
. . The cold, lightless and energy-poor conditions under the seafloor provide a promising research analog for the harsh conditions in subsurface Martian soil or near hydrothermal vents on Europa, Jupiter's second moon.
. . They're genetically distinct from life on Earth's surface and oceans. The Archaea the Penn State researchers found might look like bacteria, but they don't eat or work like them. While E. coli might double its numbers in 30 minutes, Archaea could take hundreds or even thousands of years to accomplish the same amount of growth.
July 17, 08: Grunting fish have helped scientists to date the origins of speech to about 400 million years ago. Toadfish and midshipman fish use a variety of different sounds to attract mates and scare off rivals.
. . Now US researchers have found that the area of a fish's brain that drives vocalization is extremely primitive. They say it suggests that the ability to communicate through sound emerged very early in the evolution of vertebrates.
. . Andrew Bass from Cornell U, who is the lead author of the paper, said: "You'll hear frogs calling, birds singing and we hear this all the time --we are familiar with this. "But I think it's fair to say that most people are unaware of the fact that many fish use sound for social communication."
. . "They make different kinds of sounds in different social contexts. Just as birds will use one call to attract a mate and another call to scare a rival off, the fish do exactly the same thing." A deep hum lures females to a male's nest; a sharp grunt is used to defend territory.
. . To investigate the origins of speech, the team looked at the area of the fish's brain that was responsible for controlling the pitch and duration of the calls, which is known as vocal patterning.
. . "We identified where this pattern generator developed in the brains of these fishes, and then we looked at where it was in frogs, birds and primates." The team discovered that the neural networks for vocalization were all situated in the same region. "We stood back and said: 'Oh my god, this is all in the same place'.
. . The team compared this information with the evolutionary "family tree" for vertebrates. Because the evolution of the fish can be traced back further than that of amphibians, birds and primates, the team was able deduce when the ability to vocalize came about.
. . Professor Bass said: "You could see that was a very ancient part of the nervous system shared by all vertebrates. "We came to the conclusion that it must have evolved early in time before these different groups emerged from the evolutionary family tree --around the time when bony fishes evolved about 400 million years ago."
July 15, 08: Pterosaurs and Kuehneosaurs were flying as far back as 225 million years ago, during the Triassic and before large dinosaurs roamed the Earth. A lot of strange creatures took to the air back then. Some large flying reptiles fed on dinosaurs. One early dinosaur appears to have been the first biplane. Other small reptiles that seemed to have wings had remained largely mysterious, however.
. . Now scientists say the smaller creatures soared between trees on strange fly-like wings and parachutes. They glided like today's flying dragons, small lizards that can extend membranes attached to movable ribs to glide short distances between trees. Smaller reptiles used extraordinary extensions of their ribs to form large gliding surfaces on the side of the body.
. . Kuehneosaurs, up to 70 cm long, were first found in the 1950s in an ancient cave system near Bristol. Their lateral wings were always assumed to be some form of flying adaptation, but their aerodynamic capability had never been studied before.
July 10, 08: Some birds, caged or not, only sing when they really need to, namely, during the breeding season. After it's over, their musical neurons die-off, and they are left tune-less.
. . But now, scientists at the U of Washington have shown they can keep the birds singing, temporarily, by stopping the action of an enzyme key to their brains' natural cell-death processes. As cell-death mechanisms are similar across species, the research could open up new avenues of research on degenerative and age-related diseases like Alzheimer's.
. . the actual suicide process is generally the same: A group of enzymes called caspases execute on the order for cellular degeneration. "In the future, physicians might be able to stabilize people who have suffered a stroke using these inhibitors", said Eliot Brenowitz, a U of Washington professor.
July 10, 08: A new species of carnivorous slug named the ghost slug because of its all-white appearance is discovered in south Wales.
July 8, 08: 50 million-year-old fossils --which have one eye near the top of their heads-- help explain how flatfish such as flounder, sole and halibut developed the strange but useful trait of having both eyes on one side. Flatfish lie on their sides at the bottom of the sea.
. . "The important thing about this study is it delivers evidence of those intermediates." The argument was that intermediate forms of these fish could not exist because there would be no survival benefit from having one eye that was slightly off center, but still on the opposite side of the head. More than 500 species of flatfishes live in fresh and salt water. They are born with eyes in the normal spot, but one eye gradually migrates to the other side of the head.
. . Biologists have theorized that maybe the changes occurred all at once with a large-scale mutation. According to this popular "hopeful monster" theory, flatfishes developed this weird trait, which luckily turned out to be very useful.
. . "It turns out they don't lie flat and completely prone on the sea floor. They actually will prop themselves up slightly (with their fins)". Once in that position, having a slightly asymmetrical eye arrangement must have proved advantageous, he said.
July 8, 08: The complex colored plumage of extinct birds which once soared over the heads of dinosaurs could soon be revealed. Scientists have shown they are able to interpret the color patterns seen in 100-million-year-old fossil feathers.
. . US researchers reveal how ancient feathers found in Brazil displayed "striking" bands of black and white. Previously, fossil experts could only guess at the range of hues exhibited by ancient birds and some dinosaurs.
. . Microscopic analysis of the dark bands showed they displayed a distinctive granular texture, made from thousands of tiny, densely-packed flattened spheres. Researchers had previously interpreted these as fossilized bacteria, preserved as the feathers decomposed. But analysis of modern birds' feathers showed a similar structure. "There are particular cells that cluster into the dark areas of modern birds called melanosomes." Lighter areas in the fossils did not show the same textures, leading the team to conclude that the feathers once displayed distinct black and white stripes.
. . But studies of other modern birds have shown that other colors are marked by distinct arrangements of melanosomes, raising the possibility of reconstructing more ornate plumage. The Yale team believes it could identify brown, red, buff and even iridescent colors. The technique may be applied to other creatures to reveal the color of fur or even eyes, the team believes.
. . "It allows you in certain cases to combine this knowledge with other information to paint quite a remarkable picture of behavior", Professor Benton said. For example, it could give researchers clues about courtship displays and mating behaviors.
Jun 30, 08: A species of chameleon in Madagascar spends most of its lifespan incubating inside its shell. After four or five months out in the world, it dies. Total pre-hatching and post-hatching existence: about 1 year.
. . In fewer than 60 days, body size for males can quadruple or quintuple as they reach adulthood. No other known four-legged animal has such a rapid growth rate and such a short life span. "One bad year could wipe out these chameleons."
. . Most mammals, reptiles, birds and amphibians typically live two to 10 years. Some, including turtles and humans can live for a century. Only a handful of animals live just a year. The males in nine species of marsupials die off after a year, for example, as do most adults in about 12 species of lizards.
. . Hatching begins with the rains in November, and, once emerged, the chameleons develop rapidly, growing up to 2.6 mm. After reaching maturity, the population reproduces, and females burrow through about a half foot of sand to lay their eggs. Once covered, the eggs wait out the dry season for the next 8 to 9 months, and all adults die. The chameleon's short life could be an adaptation to Madagascar's highly variable climate.
. . "It is amazing to think that for most of the year, this chameleon species is represented only by developing eggs buried in the ground."
Jun 26, 08: The results of a five-year study are so broad that the scientific names of dozens of birds will have to be changed in biology textbooks and birdwatchers' field guides. Here are 10 new things about birds you probably never knew:
. . 1. Hummingbirds, colorful daytime birds, evolved from drab nocturnal birds called nightjars.
. . 2. Perching birds (the largest order of living birds, including cardinals, orioles, crows, ravens, jays, swallows, sparrows, kinglets, weavers, chickadees, nuthatches and wrens) are closely related to parrots and falcons.
. . 3. Flamingos and some other aquatic birds, such as grebes (freshwater diving birds) and tropicbirds (white, swift-flying ocean birds), did not evolve from waterbirds. This suggests that birds have adapted to life on water multiple times.
. . 4. Woodpeckers, hawks, owls and hornbills look very different, but they are all closely related to perching birds.
. . 5. Vultures, previously thought to be closely related to storks, are actually members of a group called land birds.
. . 6. Falcons are not closely related to hawks and eagles, as was previously thought.
. . 7. Shorebirds are not the most primitive birds (or most basal, or at base of evolutionary tree, as biologists prefer to say), which refutes the widely held view that they gave rise to all modern birds.
. . 8. Owls, parrots and doves have few, if any, living intermediate forms linking them to other well-defined groups of birds, making it difficult to determine their evolutionary relationships.
. . 9. Tropicbirds are not closely related to pelicans and waterbirds. In fact, bird lifestyles, such as being noctural or raptorial or ocean-going, have evolved several times, not just in one family group.
. . 10. Birds have had a complex evolutionary history after an early and rapid explosion of species that occurred sometime between 65 million and 100 million years ago.
Jun 26, 08: Spain's parliament voiced its support for the rights of great apes to life and freedom in what will apparently be the first time any national legislature has called for such rights for non-humans.
Jun 25, 08: Scientists unearthed a skull of the most primitive four-legged creature in Earth's history, which should help them better understand the evolution of fish to advanced animals that walk on land. The 365 million-year-old fossil skull, shoulders and part of the pelvis of the water-dweller, Ventastega curonica, were found in Latvia. Even though Ventastega is likely an evolutionary dead-end, the finding sheds new details on the evolutionary transition from fish to tetrapods. This all happened more than 100 million years before the first dinosaurs roamed Earth.
. . While an earlier discovery found a slightly older animal that was more fish than tetrapod, Ventastega is more tetrapod than fish. The fierce-looking creature probably swam through shallow brackish waters, measured about three or four feet long and ate other fish. It had a real tail fin at the back end, a gill flap at the side of the head; also lines of pores snaking across head and body.
. . "These fossils were found in compact, wet sand. It's not sandstone, it's sand; you dig it with a breadknife. They're fragile but superbly preserved. They are actually three dimensional, not flat. It makes it very easy to interpret the skeleton."
Jun 25, 08: The underwater world and the underworld have at least one thing in common —-lots of aliases. The Census of Marine Life, an effort to catalog all species of life in the oceans, has validated 122,500 species names so far, as well as 56,400 aliases, different names that have been applied to the same species over the years. About a third of all types of fish and other marine life have been wrongly named by scientists, complicating efforts to conserve what could be a million marine species, experts said.
. . "It will eliminate the misinterpretation of names, confusion over Latin spellings, redundancies and a host of other problems that sow confusion and slow scientific progress. Convincing warnings about declining fish and other marine species must rest on a valid census."
. . The first Census of Marine Life is expected to be released in 2010 including more than 230,000 species, but that is only a fraction of the species thought to exist in the oceans.
Jun 24, 08: At least 11 species of African frogs carry a built-in concealed weapon --they can sprout claws on demand to fight off attackers, U.S. researchers reported. When threatened, the frogs can puncture their own skin with sharp bones in their toes that they then use to claw their attackers, David Blackburn and colleagues at Harvard U reported.
. . "It's surprising enough to find a frog with claws", Blackburn, a graduate student, said. "The fact that those claws work by cutting through the skin of the frogs' feet is even more astonishing. These are the only vertebrate claws known to pierce their way to functionality. Most vertebrates do a much better job of keeping their skeletons inside."
Jun 18, 08: Female chimps keep quiet during sex to keep other females from finding out and punishing them for mating with the best males, British researchers said.
. . The study of chimp copulation calls also found that females seem more concerned with having sex with as many mates as possible rather than just finding the strongest male as a way to confuse paternity and secure future protection for offspring. "They are trying to make the high-ranking males think they are the father. If you confuse paternity, they are more likely to provide that female with future support."
. . The female chimps called out for sex partners for as many as 12 days during their reproductive cycle, even though they were only fertile for about 4 days of it.
Jun 16, 08: There are more species of bees buzzing around the globe than there are species of mammals and birds combined, a new census shows. This new count of bee species, conducted by John S. Ascher of the American Museum of Natural History, comes from a list he compiled of more than 19,200 described bee species. But while honey bees are the most well-known bee faces, most bees don't make honey or live in hives like this social species.
. . Scientists don't even know how many total species live on the planet --estimates run from 5 million to 100 million total species, though only 2 million have been identified.
Jun 10, 08: Researchers say they have discovered groups of the silver-haired monkeys in Indonesia that fish. Groups of long-tailed macaques were observed four times over the past eight years scooping up small fish with their hands and eating them along rivers in East Kalimantan and North Sumatra provinces, according to researchers from The Nature Conservancy and the Great Ape Trust. The species had been known to eat fruit and forage for crabs and insects, but never before fish from rivers.
. . Some other primates have exhibited fishing behavior, Meijaard wrote, including Japanese macaques, chacma baboons, olive baboons, chimpanzees and orangutans.
Jun 5, 08: Cuttlefish recognize prey before they have hatched, the first known embryos to show such an ability.
May 28, 08: Australian scientists unveiled the fossilized remains of the oldest vertebrate mother ever discovered, a 375-million-year-old placoderm fish with embryo and umbilical cord attached.
May 22, 08: Microbes have been found living at a record depth of 1.6 km beneath the Atlantic seabed in a hint that life might also evolve underground on other planets, scientists said.
May 22, 08: The discovery of a "frogamander", a 290 million-year-old fossil that links modern frogs and salamanders, may resolve a longstanding debate about amphibian ancestry, Canadian scientists said.
May 22, 08: The largest rodent ever recorded might not have been as monstrous as was first suggested, a scientist has claimed. A fossil skull belonging to the rodent Josephoartigasia monesi was uncovered in Uruguay, where the beast roamed 2-4 million years ago. It was first thought to have weighed a whopping one ton, but new estimates suggest the animal could have weighed as little as a third of that.
May 21, 08: Scientists have discovered the tracks of a herd of 11 long-necked sauropods walking along a coastal mudflat in what is now the Republic of Yemen, the first discovery of dinosaur footprints on the Arabian peninsula.
May 20, 08: A survey of 900 high school teachers has found that 1 in 8 still teach creationism as a "valid scientific alternative to Darwinian explanations for the origin of species." Did we mention that these are science teachers?!!
May 19, 08: As irritating as morning sickness may be for pregnant women, it may protect embryos. Doctors have long known that morning sickness --the nausea and vomiting usually experienced in early pregnancy-- is actually a good sign of a healthy pregnancy, despite the discomfort it brings. Pregnant women and their embryos carry out a tug of war over the body's resources.
. . Morning sickness does not seem to occur in other mammals, only humans, the researchers noted. If morning sickness was the byproduct of conflict between mother and embryo or fetus, one might expect other mammals to have it too. Instead, morning sickness is usually triggered in specific circumstances --in response to:
. . * the sight, smell, or taste of meats and strong-tasting vegetables, which were historically likely to contain foodborne microbes or birth-defect-inducing chemicals; alcohol and cigarette smoke.
. . This all suggests morning sickness serves a useful function, evolving to protect mothers and embryos from things that may be dangerous, the researchers figure.
May 16, 08: A small molecule may have a big role in making the body clock tick, say Cambridge U researchers. Studies in mice have shown cAMP --a common signalling molecule-- is involved in keeping the body clock "rhythms" going. The team hope to develop drugs that target cAMP to help shift workers, frequent flyers or those with sleep disorders reset their body clocks.
. . But the research is still a long way from the clinic. Disruption of these "circadian" rhythms have been shown to be linked with insomnia, depression, heart disease, cancer and neurodegenerative disorders.
. . At the beginning of the circadian day, genes are switched on which then produce proteins which in turn go on to switch off the same genes at the end of the day. The proteins are broken down over the circadian night and the process starts all over again in the morning.
. . Researchers at the Medical Research Council Laboratory of Molecular Biology discovered that cAMP not only helps regulate the production of these proteins but that its own rhythm is also regulated by this "loop". "What's neat about cAMP is that it is very easily controlled by different medicines and compounds."
May 16, 08: The ancestors of humans, apes and monkeys may have taken to the trees because of their small body size. Scientists have long wondered why early primates inhabited forest canopies, given that climbing appears to consume more energy than walking.
. . US researchers studied primates climbing and walking on treadmills. They say there was no difference in energy consumption for small primates, giving clues to how their ancestors entered the trees 65 million years ago. The earliest primates were able to exploit a new environment without added cost if they remained small.
. . Early primates, which would have been about the size of large rats, then underwent a number of evolutionary changes as they adapted to their new environment. These changes included nails rather than claws and grasping hands and feet. "The benefit/payoff of invading this new environment (and the appearance of these anatomical changes) was an insect- and fruit-rich environment."
May 15, 08: Scientists say they may have discovered the reason why swarms of locusts are driven to devour such huge quantities of vegetation. They suggest that locusts combine into swarms because they are frightened of being eaten by each other.
. . A swarm can contain billions of insects and eat tens of thousands of tons of vegetation in a single day. They are usually herbivores, but scientists have observed them eating each other. This is when they cannot get hold of enough food when normal supplies start to run short.
. . Increasing numbers of locusts band together to try to get away from the hungry cannibals chasing behind. They keep this momentum when they reach the adult phase of their life cycle and take to the air.
May 14, 08: The sloth's popular image as a lazy creature that sleeps for most of the day has been called into question. Rather than snoozing for more than 16 hours a day, as observed in captivity, sloths in the wild doze for 9.6 hours, research suggests. Scientists caught sloths living in the rainforest of Panama and fitted them with a device that monitors sleep. Animals vary in the amount of sleep they need. Pythons, for example, sleep for 18 hours a day, while giraffes survive on just two hours.
May 14, 08: Super-fast pilot whales have been observed sprinting after prey, likely to include giant squid. The rapid pursuit has brought comparisons with the fleet-footed land predator, the cheetah. The cetaceans even use the same, highly specialized hunting strategy that cheetahs use, scientists report.
. . It is the first time such remarkable behavior --occurring hundreds of meters underwater, in complete darkness-- has been recorded. When they pinpoint their prey, the whales surge after it, reaching speeds of nine meters per second, or 32 kph. What's more, they may keep up the sprint for 200m, before either catching the prey or giving up the chase.
May 14, 08: In humans, the eyes are said to be the "window to the soul", conveying much about a person's emotions and intentions. New research demonstrates for the first time that birds also respond to a human's gaze.
. . Predators tend to look at their prey when they attack, so direct eye-gaze can predict imminent danger. Julia Carter, a graduate student at the U of Bristol, and her colleagues, set up experiments that showed starlings will keep away from their food dish if a human is looking at it. However, if the person is just as close, but their eyes are turned away, the birds resumed feeding earlier and consumed more food overall.
May 14, 08: Mantis shrimps, dubbed "thumb splitters" by divers because of their vicious claws, have the most complex eyes in the animal kingdom, capable of seeing colors from the ultraviolet to the infrared, as well as detecting other subtle variations in light. They view the world in up to 12 primary colors --four times as many as humans-- and can measure six different kinds of light polarization, Swiss and Australian researchers reported.
. . "Some of the animals they like to eat are transparent and quite hard to see in sea-water, except they're packed full of polarizing sugars. I suspect they light up like Christmas trees as far as these shrimp are concerned." And the shrimps probably use tiny changes in color and polarization to send sexual signals between males and females, the researchers believe.
May 11, 08: The secret behind growing large tomatoes lies not in the fertilizer or the perfect soil conditions, but in just a few genetic changes that over time have resulted in tomatoes 1,000 times bigger than their wild ancestors, U.S. researchers said. Without these changes, tomatoes would be little more than berries on a bush. "The cherry tomato would be considered very large compared to what is found in the wild", said plant geneticist Steven Tanksley of Cornell U --they're naturally about the size of a blueberry.
. . Tanksley focused on the genetic changes that give rise to a large number of compartments or locules inside the tomato, a plant that originated in the Americas. "If you take a beefsteak tomato from the supermarket and cut it open, inside you'll see ... compartments in there that have wells between them. They may have anywhere from 10 to 20 of these compartments." A true wild tomato may have only two to four of these. A mutation weakens a signal that tells the plant to stop making compartments.
. . In prior research, Tanksley's team found changes in a similar gene that told cells to stop dividing. "It would tell the developing, very small fruit to stop here."
May 8, 08: Flowers "wave" at insects to get their attention, scientists have discovered. The finding helps explain why many flowers waft in the breeze, and reveals a hitherto unknown trick used to attract pollinators. Scientists made the discovery while studying common wildflowers known as sea campion on the Welsh coast. Mobile flowers are visited more often by insects and also produce more seeds, they report.
. . Their experiments reveal that flowers mounted on long, thin stalks move around more in the wind. This acts as a powerful signal to passing pollinators, allowing the plant to attract more insects than less mobile flowers growing atop short, thick stems. Yet, very wobbly flowers are just too wobbly for the insects to handle, as the insects cannot land on them.
May 8, 08: Orchids that mimic female wasps may not only waste the time of the male wasps they lure into spreading their pollen --they also seduce them into wasting valuable sperm, Australian researchers reported.
. . And the flowers benefit twice --getting help in their own reproduction, and perhaps indirectly producing more male pollinators in the process. Some of the orchids are known to have evolved their convoluted shapes to attract insects, who unwittingly collect and transfer pollen as they try to mate with the flowers.
. . It is not harmless to the wasps, who may suffer more than an inconvenience. "Male pollinators can prefer orchids to real females, prematurely end a copulation with a real female to visit an orchid, or be unable to find real female mates among false orchid signals", the researchers wrote.
. . "Unquestionably, producing sperm, ejaculate, or seminal fluids is costly for many animals. The energetic demands of sperm production can result in reduced body mass, a shortened life span, or limited lifetime sperm production", they added.
. . But this arms race of sexual trickery works in more than one way for the flower. "We also show that orchid species provoking such extreme pollinator behavior have the highest pollination success", they added.
. . The wasps who frequent these flowers are haplodiploid species. Like bees, ants and similar species, offspring produced by sexual unions are female, while females can also produce males asexually, which may even enhance orchid pollination."
May 7, 08: The genetic blueprint of one of the world's strangest mammals --the duck-billed platypus-- is deciphered. The animal comes from an early branch of the mammal family, and like mammals it is covered in fur and produces milk. However, it lays eggs like a reptile. Researchers say this unique mixture of features is reflected in its DNA. The genome sequence holds clues to how humans and other mammals first evolved, they add.
. . The platypus and the small spiny mammal known as the echidna are the only existing species of monotremes in the world. They have acute sight, but only open their eyes above water. Underwater, they rely on touch and a special sense called electro-reception that allows them to detect tiny changes in the electrical field generated by their prey.
. . "What we found was the genome, just like the animal, is an amazing amalgam of reptilian and mammal characteristics with quite a few unique platypus characteristics as well." Males have venom-filled spurs on their heels --the pain-causing poison that males can use to ward off mating rivals.
. . The research contained some surprises, such as the conclusion that genes which determine sex in a platypus are similar to those of a bird, not a mammal. Researchers also found genes that indicate platypuses — which rely on electrosensory receptors in their bills to navigate as they rummage with closed eyes in waterways — may also be able to smell underwater.
. . The scientists compared the platypus genome with human, mouse, dog, opossum and chicken genomes and found that the platypus shares 82% of its genes with these animals. It has 10 sex chromosomes, 5 male and 5 female. Humans only have one of each.
. . The genome of the platypus, which unlike other mammals carries its testicles internally, allowed them to study two genes that move testes into the scrotum in most mammals. They said understanding this process may explain why testes of about 30% of premature boys fail to descend properly.
May 2, 08: A team found that male jumping spiders (Phintella vittata) are using ultraviolet B (UVB) rays to communicate with females. While UVA rays are often used in animal communication, this is the first evidence that UVB light is also being used, the researchers said.
. . The researchers discovered that females were more likely to mate with males that could "talk" to them with UVB compared with spiders sitting in chambers where UVB light had been blocked with filters. "Until now, scientists have assumed that animals cannot 'see' UVB, but we have found that this is not the case."
May 1, 08: Fossil microbes found along an iron-rich river in Spain reveal how signs of life could be preserved in minerals found on Mars. The discovery may help to equip the next generation Mars rover with the tools it would need to find evidence of past life on the planet.
. . Rio Tinto has attracted the attention of exobiologists because this environment can create the iron mineral hematite, which has been found on Mars. On Earth, hematite only forms with liquid water. Since liquid water is seen as a prerequisite for life elsewhere, the mineral's presence on Mars tantalizes those who hope to find signs of life, past or present, on our neighboring planet.
May 1, 08: The happy babbling that entertains parents as their babies try to mimic speech turns out to have a parallel in the animal world. Baby birds babble away before mastering their adult song, researchers report.
May 1, 08: As if using million-year-old fossil fragments to divine the cognitive, social and physical evolution of our ancestors isn't hard enough, paleoanthropologists face yet another challenge: Obvious adaptations aren't necessarily obvious.
. . The Nutcracker Man didn't eat nuts. In a study, anthropologist Peter Ungar microscopically analyzed the teeth of Paranthropus boisei, an early branch of the human family tree.
. . Flat, thickly-enameled teeth and an enormous jawbone led scientists to surmise that P. boisei ate hard-to-chew foods, earning him the nickname of "Nutcracker Man." But Ungar's team saw none of the wear-and-tear expected from a diet of hard, brittle foodstuffs. Instead, P. boisei appears to have preferred fruit.
. . In recent years, paleoanthropologists have suggested that specializations like P. boisei's teeth arose not to take advantage of a preferred food source, but a fallback source -- something that was consumed rarely, most likely in lean times when other foods ran short.
Apr 30, 08: Marine scientists studying the carcass of a rare colossal squid said they had measured its eye at about 11 inches across, with a lens as big as an orange —-making it the largest animal eye on Earth. It captures an awful lot of light in the dark depths in which it hunts. The squids can descend to 6,500 feet and are known to be aggressive hunters.
. . When caught, it measured 26 feet long and weighed about 1,000 pounds, but scientists believe the species may grow as long as 46 feet.
Apr 30, 08: Australian scientists have come up with an apple that does not go brown when cut.
Apr 29, 08: Even the pinhead-sized brains of insects can learn new skills from their comrades --including theft. It seems bumblebees can discover how to "rob" flowers of nectar, scientists now reveal.
. . Normally, bumblebees crawl into flowers to get nectar. In return for this sweet treat, blossoms coat the insects in pollen, which contains plant sperm. When these bees rendezvous with other flowers, they serve as couriers of this pollen, helping the plants breed.
. . However, bees can bite through the base of a flower to suck up nectar instead, avoiding the pollen altogether. Since they get something for nothing this way --drinking nectar without helping the flowers mate-- such behavior can be seen as theft. The bees may commit such an act to get nectar from blossoms they could not fit into, or just to get more nectar than possible by normal means.
. . Now it appears that bumblebees can quickly learn how to rob flowers if they visit blossoms that others have already burglarized. The bees could learn how to commit such theft by themselves, but this was rare. But, after one bee learned how to rob nectar by watching its comrades, the skill rapidly spread to other bees.
. . It was long known that bees could learn simple facts from each other --such as where food is, for instance-- but the discovery that insects can learn skills from others is a first. The brains of bumblebees are a little larger than 1 cubic millimeter in size, or nearly one-millionth the size of a human brain.
. . "It was actually first suggested in one of Darwin's journals. He saw bumblebees robbing flowers in a garden one day, and saw honeybees doing something similar afterward."
Apr 24, 08: Scraps of protein from the bones of a 68 million-year-old dinosaur and a mastodon carcass confirm their places in the family tree of life on Earth, researchers reported. The same team that established T rex is a distant relative of chickens filled in more gaps, showing that the dinosaur was far more closely related to living birds than to alligators. And a 500,000-year-old mastodon is clearly a close relative of elephants.
. . They said their analysis of the ancient preserved proteins can be used to fill in all sorts of gaps in the tree of evolution. But it also shows that classical methods, based on studying an animal's bones and other physical structures, are accurate. They weren't able to recover dinosaur DNA, the genetic instructions for life, but DNA codes for the proteins they *did study.
. . Their improved argon-argon dating method places the Cretaceous-Tertiary, or K/T, boundary at 65.95 million years ago, give or take 40,000 years. Earlier estimates had put it at 65.5 million years ago, with a 300,000-year margin of error.
Apr 24, 08: Ancient humans started down the path of evolving into two separate species before merging back into a single population, a genetic study suggests. The results have come from the Genographic Project, a major effort to track human migrations through DNA.
. . The genetic split in Africa resulted in distinct populations that lived in isolation for as much as 100,000 years, the scientists say. This could have been caused by arid conditions driving a wedge between humans in eastern and southern Africa.
. . But other scientists said it was still too early to reconstruct a meaningful picture of humankind's early history in Africa. They argue that other scenarios could also account for the data.
. . At the time of the split --some 150,000 years ago-- our species, Homo sapiens, was still confined to the African continent. It would be the longest period for which modern human populations have been isolated from one another. "They came back together again during the Late Stone Age --driven by population expansion."
. . The researchers compiled a "family tree" of different mitochondrial DNA groupings found in Africa. A major split occurred near the root of the tree as early as 150,000 years ago. On one side of this divide are the mitochondrial lineages now found predominantly in East and West Africa, and all maternal lineages found outside Africa.
. . On the other side of the divide are lineages predominantly found in the Khoi and San (Khoisan) hunter-gatherer people of southern Africa.
. . Modern humans are often presumed to have originated in East Africa and then spread out to populate other areas. But the data could equally support an origin in southern Africa followed by a migration to East and West Africa. This divergence could have been related to climate change: recent studies of ancient climate data suggest that eastern Africa went through a series of massive droughts between 135,000-90,000 years ago.
. . The genetic data show that populations came back together as a single, pan-African population about 40,000 years ago. This renewed contact appears to coincide with the development of more advanced stone tool technology and may have been helped by more favorable environmental conditions.
. . "This study illustrates the extraordinary power of genetics to reveal insights into some of the key events in our species' history." Our population could've been as low as 2,000 before numbers began to expand again in the early Stone Age. Tiny bands of early humans, forced apart by harsh environmental conditions, coming back from the brink to reunite and populate the world. Truly an epic drama, written in our DNA."
. . Previous studies using mitochondrial DNA —-which is passed down through mothers-— have traced modern humans to a single "mitochondrial Eve", who lived in Africa about 200,000 years ago. The migrations of humans out of Africa to populate the rest of the world appear to have begun about 60,000 years ago, but little has been known about humans between Eve and that dispersal.
Apr 24, 08: During the Jurassic, abrupt global warming of between 5 and 10 degrees C was associated with severe environmental change. Many organisms went extinct and the global carbon cycle was thrown off balance. One of the most intriguing effects was that the oxygen content of the oceans became drastically reduced, and this caused many marine species to die off.
. . These intervals of reduced oxygen content in the oceans are now known as oceanic anoxic events, or OAEs. OAEs are associated with periods of global warming and have occurred a few times in Earth's history.
. . During OAEs, the remains of dead organisms and other organic matter accumulate on the ocean floor and became layers of organic-rich sediments. Today, scientists are examining the chemical and isotopic compositions of these sedimentary deposits in order to determine the actual extent to which the oceans became anoxic.
Apr 23, 08: Papayas have extra copies of genes that make them sweet and nutritious, researchers reported on Wednesday in a study that can help shed light on how flowering plants evolved. They published the complete genetic sequence of the "SunUp" papaya, a tree genetically engineered to be virus resistant.
. . They believe they have pinpointed genes responsible for helping tree-like plants evolve, and genes that helped make it smell and taste so good, attracting animals and people to spread its seeds. Papayas have extra genes that appear to code for these aromas and for storing starch, presumably in the fruit.
. . "Papaya is ranked first on nutritional scores among 38 common fruits, based on the percentage of the US Recommended Daily Allowance for vitamin A, vitamin C, potassium, folate, niacin, thiamine, riboflavin, iron and calcium, plus fiber", they wrote.
Apr 23, 08: A fish species, which is all female, has survived for 70,000 years without reproducing sexually, experts believe. Scientists from the U of Edinburgh think the Amazon Molly may be employing special genetic survival "tricks" to avoid becoming extinct.
. . The species, found in Texas and Mexico, interacts with males of other species to trigger its reproduction process. The offspring are clones of their mother and do not inherit any of the male's DNA.
. . Typically, when creatures reproduce asexually, harmful changes creep into their genes over many generations. Researchers calculated the time to extinction for the fish based on modelling genetic changes over many thousands of generations. They are now able to say conclusively, for the first time, the fish ought to have become extinct within the past 70,000 years, based on the current simple models.
. . Scientists believe the fish, which are still thriving in rivers in south-east Texas and north-east Mexico, are using special genetic survival "tricks" to help them stay alive. One theory is that the fish may occasionally be taking some of the DNA from the males that trigger reproduction, in order to refresh their gene pool. "Maybe there is still occasional sex with strangers that keeps the species alive."
Apr 23, 08: Someone seeing for the first time a placenta spill out of a woman's body after childbirth is likely surprised at how large it is and might wonder where it really came from. Scientists have no clue, either, at least insofar as evolution is concerned. The gooey thing, which looks like a big, red kidney, is rather reptilian in its ancestry, new research suggests.
. . The placenta develops inside the womb and supplies a fetus with oxygen and nutrients and ensure a mother's body does not reject the fetus, just as it might normally attack a germ, parasite or transplanted organ.
. . "The placenta is [an] amazing, complex structure and it's unique to mammals, but we've had no idea what its evolutionary origins are", said researcher Julie Baker, a molecular biologist at Stanford U in California.
. . Now Baker and her colleague have discovered that the inner lining of eggs laid by the distant ancestors of all mammals could be the origin of the placenta, and the whole setup evolved as mammals employed leftover reptilian-like genes. A better understanding of all this could shed light on pregnancy and disorders linked to it, the researchers say.
. . These findings suggest the placenta initially evolved when early mammals found new uses for genes they inherited from their reptile-like ancestors. For instance, there is a simple tissue attached to the inside of eggshells that currently allows unborn reptiles and birds to absorb oxygen from the air. The placenta might have evolved from similar tissues, although the placenta is far more complex.
. . An elephant's placenta has to nourish a single unborn creature for 660 days. A pregnant mouse, on the other hand, nurtures an average of 12 offspring for just 20 days. Such pregnancies would require very different placentas.
. . The mammalian placenta originates from a cell type known as trophoblasts that are not found in any other kind of animal, even platypuses and other egg-laying mammals.
. . Nobody even knows for sure what triggers labor. Previous research suggests the placenta may be involved. The placenta is also suspected to be linked to the leading cause of premature births, a condition known as pre-eclampsia.
Apr 23, 08: "Hello? Yes, this is my plant. Thanks. Bye-bye." That's the underground half of a conversation between bugs on a mustard plant. Scientists have discovered the insects below and above use the plant like a chemical telephone. They're not sure how widespread the phenomenon is.
. . The organic chat is a friendly one: Leaf-munching insects above ground prefer plants unoccupied by root-eaters. When a subterranean insect takes up residence below a plant, it settles in to feast on the plants' roots. In order to alert leaf-eating insects of the "no vacancy", the underground insect sends a chemical warning signal through the plant leaves, so the leafeaters are alerted that the plant is occupied.
. . The green phone lines keep insects from unintentionally competing for the same plant. Turns out, the subterranean insects can also communicate with a third party via the biophone, namely the natural enemy of caterpillars --parasitic wasps.
. . The chemicals emitted by the leaves give the wasps information about the occupancy of different plants. Since the parasitic wasps lay their eggs inside aboveground insects, they would do well to stop by plants unoccupied by the underground root-eaters.
Apr 18, 08: A tree said to be the oldest on the planet --thought to be nearly 10,000 years old-- has been found in Sweden. Scientists from Umeaa U discovered the spruce on Fulu Mountain in Dalarna province while carrying out a census of tree species there. The age of its genetic material was recently calculated using carbon dating.
. . The spruce's stems or trunks had a lifespan of around 600 years, but as soon as one died, a cloned stem could emerge from the root system. The clones take root each winter as snow pushes low-lying branches of the mother tree down to ground level.
Apr 17, 08: Aversion to inbred men isn't just a sensible cultural tradition. It might be biologically hard-wired into women who are literally able to sniff out the scent of incest.
. . In a study, researchers from the U of Liverpool bred two groups of male mice to be identical in every way but one: the diversity of their so-called major urinary proteins.
. . Lacking Google stalking and the advice of embittered friends, female mice rely on urinary proteins for information about potential mates. In the wild, mice born to genetically unrelated parents have more varied proteins than the offspring of related parents --and in the Liverpool lab, female mice consistently picked males with the most complex urinary bouquet.
. . Do human women have the same ability? Scientists don't know --but it's certainly plausible. Olfactory cues are among the tricks we instinctively use to detect unsuitable mates.
Apr 16, 08: A mother has given birth to a rare set of quadruplets in which three of the four boys are identical. The boys were born 11 weeks premature in January at Greater Baltimore Medical Center.
Apr 16, 08: Borneo's mysterious pygmy elephants may be the descendants of Javan elephants accidentally saved from extinction by a local sultan several centuries ago, the conservation group WWF said. Pygmy elephants, so called because they are smaller and less aggressive than mainland Asian elephants, number perhaps 1,000 today and live in lowland forests in Borneo that are shrinking under the threat from timber, rubber and palm oil plantations.
. . New research supports a long-held local belief that the elephants were brought to Borneo centuries ago by the Sultan of Sulu and abandoned in the jungle. The Sulu elephants are thought to have originated in Java, where elephants became extinct some time in the period after Europeans arrived in South-East Asia.
. . DNA tests in 2003 had ruled out the possibility the Borneo elephants were from Sumatra or mainland Asia, home of the other Asian subspecies, leaving either Borneo or Java as the most probable source.
Apr 16, 08: Researchers from the Cleveland Metroparks Zoo have discovered a rare giant turtle in northern Vietnam —-a find that carries great scientific and cultural significance. Swinhoe's soft-shell turtle was previously thought to be extinct in the wild. Three other turtles of the species are in captivity, said experts from the Zoo's Asian turtle program. The discovery represents hope for the species.
Apr 16, 08: A six-ton orca, or killer whale, torpedoes toward the beach, its dorsal fin cutting the Patagonian sea. It launches itself onto the sand in an explosion of water and foam. Before the waters die down, the orca is shaking its immense head from side to side with a sea lion pup clamped between his jaws. Then the orca wriggles into position to catch a wave to carry it back out to sea.
. . Only seven orcas in the world are known to hunt this way, all of them members of a pod that patrols the coast of Patagonia's Valdes Peninsula at this time of year. It happens almost exclusively in March and April --early autumn in the southern hemisphere-- when baby sea lions are learning to swim.
. . This hunting method is risky. Whales can die if they remain out of water, so they have to time the waves and judge distances carefully. They use sonar --orcas are members of the dolphin family-- to hunt, and only beach themselves in high tide, on steep and pebbly beaches that help them roll back.
Apr 16, 08: A study in Pakistan found that "three out of five marriages were between first cousins." Another in India that found "one-fifth of marriages occurred between uncles and nieces and a third between first cousins."
. . The incest taboo does have a firm biological basis. As Callaway explains, "Inbreeding ups the chances that a child will inherit two versions of a disease-causing gene." Data show higher mortality among infants born from first-cousin pairs.
Apr 16, 08: Neandertals have spoken out for the first time in 30,000 years, with the help of scientists who have simulated their voices using fossil evidence and a computer synthesizer. Robert McCarthy, an anthropologist at Florida Atlantic U in Boca Raton, used new reconstructions of Neandertal vocal tracts to work out how they would have sounded.
. . The conclusion is that Neandertals spoke, but sounded rather different than us. Specifically, the ancient humans' lacked the "quantal vowel" sounds that underlie modern speech and which provide cues that help speakers understand one another.
. . By modeling the sounds that a Neandertal larynx would have made, McCarthy's team engineered the sound of a Neandertal saying "e." (To listen to that simulation of a Neandertal voice, visit: http://media.newscientist.com/data/images/ns/av/dn13672A1.wav). He aims eventually to simulate an entire Neandertal sentence.
Apr 15, 08: An ancient ancestor of the elephant from 37 million years ago lived in water and had a similar lifestyle to a hippo, a fossil study has suggested. The animal was said to look similar to a tapir, a hoofed mammal which looks like a small horse. Experts analyzed chemical signatures preserved in fossil teeth. These indicated that the animal grazed on plants in rivers or swamps.
. . DNA evidence suggests that elephants are related to seagoing manatees and dugongs, and another land-based mammal, the rabbit-like hyrax. The isotopic signals suggest that Barytherium and Moeritherium, as they are called, were largely aquatic, feeding on freshwater vegetation in rivers or swamps.
. . At the time, the deserts of northern Egypt, where the teeth were unearthed, were covered by sub-tropical rainforest and swamps. One theory is that a cooling event at the end of the Eocene dried up swamps and rivers, forcing animals out on to the land. "There's little real evidence yet to suggest that's true."
Apr 7, 08: The notion that children's taste in toys might somehow be genetically determined has long been disparaged by psychologists, pooh-poohed as unscientific, sexist or both. But a study by researchers in the US suggests that when it comes to choosing between trucks and cuddly stuffed animals, chromosomes could make a difference.
. . By the time kids are old enough to choose and play with toys, they have also been socialised --picking up cues from their parents, peers and television-- on how little girls and boys should behave, making it impossible to tease the two influences apart.
. . So a team of scientists decided to offer typical "male" and "female" toys to rhesus monkeys to see if preferences aligned with sex. Much to their surprise, they did. The 11 male monkeys headed straight for the wheeled toys, such as dump trucks, leaving the plush toys more-or-less unmolested. The 23 females were more curious, and played with both.
Apr 7, 08: The first lungless frog has been discovered lurking in the jungles of Borneo. The enigmatic amphibian, dubbed Barbourula kalimantanensis, apparently gets all the oxygen it needs through its skin. Scientists first saw one of these frogs 30 years ago, but due to their rarity, just one other specimen had been collected since then and neither had been dissected.
. . The amphibians, no more than 2 inches long, have proven elusive because they live in cold, fast rivers in remote areas of the rainforests of Kalimantan, the Indonesian part of Borneo. Also, they are slippery "and can be surprisingly fast for short bursts", Bickford said.
. . It appears that the rest of the internal organs in these frogs have shifted position to take up the space once filled by the lungs. "So we had the stomach, spleen and the liver up in the area where lungs are normally found", Bickford said. "Interestingly, we also discovered some abnormal cartilage around the area where the lungs should have been that we are still investigating."
. . The loss of lungs helped the frogs severely flatten their bodies. This in turn increased the surface area of their skin, which helps them absorb oxygen. The researchers conjecture the loss of lungs might be an adaptation to the cold, fast rivers the frogs live in. Such waters naturally have high oxygen content. Also, the frogs would rather sink than float and get carried away in the water, so getting rid of lungs, which behave as flotation devices, would prove helpful.
. . Amphibians are also cold-blooded, "so their inherent energy requirements are very small --roughly 10% that of a similar sized mammal."
. . The loss of lungs has been known to occur two other times in all the creatures with backbones that have waddled onto land across geologic time. Each time this loss has happened in amphibians --in a species of caecilian, a limbless beast resembling an earthworm, and in many species of salamanders.
. . "Their future is being destroyed by illegal gold mining by people who are marginalized and have no other means of supporting themselves", Bickford said. "There are no simple answers to this problem." One of the primary goals of the researchers now is to garner more support for conserving the last remaining wild spots in Borneo.
Apr 3, 08: A U of Washington professor says a recently discovered fish that crawls instead of swimming and has forward-looking eyes like humans could be part of an entirely unknown family of fishes.
. . The creature sighted in Indonesian waters off Ambon Island has tan- and peach-colored zebra-stripping. It uses its leglike pectoral fins to burrow into cracks and crevices of coral reefs in search of food. UW professor Ted Pietsch says this relative of the anglerfish will have to undergo DNA scrutiny to verify that it is unique. But the world's leading authority on anglerfish says he's never seen anything like it.
Apr 14, 08: Cellulose dating back 253 million years —-along with some possible ancient DNA-— has been found in salt crystals from an underground nuclear waste dump in southern New Mexico. "We did see some ancient DNA in the salt, but not a lot, and we have to continue experiments to try to verify that it is."
. . The cellulose —-the same microscopic stuff in wood or cotton-— was in water locked in tiny cubes of clear and reddish-brown salt crystals. Griffith said he thinks looking for cellulose in salt deposits is a good way to go searching for life on other planets because cellulose is tough.
. . He and his colleagues used a tiny drill —-about the width of a cat's whisker-— to bore into the water-bearing cubes to retrieve drops water as large as one from a standard eyedropper. The ancient cellulose was not fossilized —-a process in which biological material is replaced by minerals, making a rock. Plants, algae and bacteria generate about 100 gigatons of cellulose a year, he said.
Apr 11, 08: Scientists have found a cluster of spruces in the mountains in western Sweden which, at an age of 8,000 years, may be the world's oldest living trees.
Apr 11, 08: Earth's first animal was the ocean-drifting comb jelly, not the simple sponge, according to a new find that has shocked scientists who didn't imagine the earliest critter could be so complex.
. . The tree of life is a hierarchy of evolutionary relationships among species that shows which groups split off on their own evolutionary path first. The new study surprisingly found that the comb jelly was the first animal to diverge from the base of the tree, not the less complex sponge, which had previously been given the honor.
. . Dunn's team checked and re-checked their results and came up with the same result every time: the comb jelly came first.
. . Unlike sponges, comb jellies have connective tissues and a nervous system, and so are more complex. Though squishy and tentacled, they are not, however, true jellyfish as they lack the classic bell-shaped body and characteristic stinging cells.
. . The finding was unexpected because evolutionary biologists had thought that less complex animals split off and evolved separately first. Dunn says that two evolutionary scenarios can explain why the comb jellies would actually have been first among animals. The first is that the comb jelly evolved its complexity independent of other animals after branching off to forge its own path.
. . The second is that the sponge evolved its simpler form from the more complex form. This second possibility underscores the fact that "evolution is not necessarily just a march towards increased complexity", Dunn said. Dunn and his team hope that their approach will fill other gaps in the tree of life, including where the branches of many of today's species belong.
Apr 10, 08: A fossil animal locked in Lebanese limestone has been shown to be an extremely precious discovery --a snake with two legs. Scientists have only a handful of specimens that illustrate the evolutionary narrative that goes from ancient lizard to limbless modern serpent.
. . Researchers used intense X-rays to confirm that a creature imprinted on a rock, and with one visible leg, had another appendage buried just under the surface of the slab. The stumpy hind-limb is only 2cm long, and was presumably utterly useless to the animal in life. "We can even see ankle bones." Current evidence suggests that snakes started to emerge less than 150 million years ago.
. . Two theories compete. One points to a land origin in which lizards started to burrow, and as they adapted to their subterranean existence, their legs were reduced and lost - first the forelimbs and then the hind-limbs.
. . The second theory considers the origin to be in water, from marine reptiles.
. . Look at some of the more primitive modern snakes, such as boas and pythons, and you'll see evidence of their legged ancestry --tiny "spurs" sited near their ends, which today are used as grippers during sex.
Apr 10, 08: An environmental scientist from England believes that even if some planets turn out to be Earth-like, the odds are very low they'll have intelligent inhabitants. Professor Andrew Watson of the U of East Anglia describes an improved mathematical model for the evolution of intelligent life as the result of a small number of discrete steps.
. . Evolutionary step models have been used before, but Watson (a Fellow of England's Royal Society who studied under James Lovelock, inventor of the "Gaia hypothesis") sees a limiting factor: The habitability of the Earth (and presumably, other living worlds) will end as the sun brightens. Like most stars, as it progresses along the main sequence, the sun's output increases (it is believed to be about 25% brighter now than when the Earth formed). Within at most 1 billion years, this will raise the average temperature of the Earth to 50 degrees C, rendering the planet uninhabitable.
. . Watson finds that approximately four major evolutionary steps were required before an intelligent civilization could develop on Earth. These steps probably included the emergence of single celled life about half a billion years after the Earth was formed, multicellular life about a billion and a half years later, specialized cells allowing complex life forms with functional organs a billion years after that, and human language a billion years later still. Several of these steps agree with major transitions that have been observed in the archeological record.
. . Watson estimates the overall probability that intelligent life will evolve as the product of the probabilities of each of the necessary steps. In his model, the probability of each evolutionary step occurring in any given epoch is 10% or less, so the total probability that intelligent life will emerge is quite low (less than 0.01% over 4 billion years). Even if intelligent life eventually emerges, the model suggests its persistence will be relatively short by comparison to the lifespan of the planet on which it developed.
. . Asked if an advanced, space-faring civilization might be able to survive the brightening of its star by migrating off the planet where it evolved, Watson agrees that's possible: "the model predicts only when 'intelligence' can arise based on the time available. Once the observers exist, they might do all manner of things to find new places to live."
Apr 1, 08: Marine biologists studying wild octopuses have found a kinky and violent society of jealous murders, gender subterfuge and once-in-a-lifetime sex. The new study journeyed off the coast of Indonesia found that wild octopuses are far from the shy, unromantic loners their captive brethren appear to be.
. . They witnessed picky, macho males carefully select a mate, then guard their newly domesticated digs so jealously that they would occasionally use their 8-to-10-inch tentacles to strangle a romantic rival to death.
. . The researchers also observed smaller "sneaker" male octopuses put on feminine airs, such as swimming girlishly near the bottom and keeping their male brown stripes hidden in order to win unsuspecting conquests.
. . Shortly after the female gives birth, about a month after conception, both the mother and father die. "It's not the sex that leads to death", said Christine Huffard, the study's lead author. "It's just that octopuses produce offspring once during a very short lifespan of a year."
Apr 1, 08: Tafforeau is a palaeontologist. But whilst others of his profession will be in the dirt with a rock hammer and trowel, you'll find him at the end of one of the most remarkable "cameras" in the world. The European Synchrotron Radiation Facility (ESRF) in Grenoble, France, produces an intense, high-energy light that can pierce just about any material, revealing its inner structure.
. . Tafforeau and colleague Malvina Lak have put kilos of opaque amber chunks in the way of this beam and have found a treasure trove of ancient organisms. From more than 600 blocks, they have identified nearly 360 fossil animals. Wasps, flies, ants --even spiders. There are also small fragments of plant material.
. . As he plays with the settings, what starts out as grey nothingness suddenly becomes the unmistakable outline of a "wee beastie". Who knows? This little creature could once have buzzed a dinosaur. It's certainly the right age. One of the discovered mites measures just 0.8mm across. This virtual insect can be spun around on the computer screen. With resolution on the micron scale (millionths of a meter), fine anatomical details jump out.
. . But here's the really neat part. All that electronic information can be fed to a 3D plastic printer to make a physical model. A bug that in reality is less than a millimeter long and hidden inside a resin block then becomes a 30cm-long facsimile you can hold in your hand.
. . "We needed four days to scan 10kg of amber. With a larger beam and a wide-field detector, in four days we would be able to scan perhaps 100kg of amber; and with even better results."
Apr 1, 08: Bonding with mom is an important part of a monkey's development. But just like with people, some kids are easy to wean, while others cling. Now a study of monkeys links these differences in attachment to a gene that's known to be important in addiction.
. . They study the mu-opioid receptor gene because it tells brain cells to make receptors that respond to opium-like molecules, including the body's natural painkillers, and other pleasure chemicals, but alsolike those in narcotics, alcohol and nicotine. Some people have a version of the gene that is much more sensitive to the rewarding effects of these chemicals than people without this version.
. . Barr says a natural place to look was at in the realm of emotional attachments, since personal and social attachments are also mediated by the brain's reward system. There's also an obvious way that increased attachment to mom could have been beneficial.
. . "The development of attachment of an infant to its mother or caregiver is critical for that infant to survive, because she provides not only nourishment, but also protection from predation and injury and other kinds of dangers."
Mar 31, 08: Rooks are members of the crow family. Rooks team up to pull a food-laden tray into their enclosure. Pairs of rooks can co-operate to solve problems, scientists report.
. . An experiment revealed that the rooks would team up so they could reach a tray of food that was inaccessible to lone birds. The researchers from the U of Cambridge were surprised to find that the birds performed as well as chimpanzees at the test.
. . The researchers presented pairs of captive birds with a tray topped with tasty morsels of egg yolk and mealworm --however, it was placed just out of reach, outside of the birds' cage. A single piece of string was threaded through two hooks on the tray, with each end left dangling. "If just one bird pulled on one end of the string, it would slip out from the loops. "The question was would they work out, without any training, that they needed one bird to pull on one end of the string and another to pull on the other, simultaneously, to get to the food?" The eight pairs were happy to cooperate, with some pairs solving the task straight away, others taking a day or two to work out that team-work was the key to getting their nibbles.
Mar 27, 08: Even as creatures become complex, evolution doesn't get any harder. The findings, published yesterday in Nature, shed doubt on a creationist criticism of evolution: that adaptation must rapidly slow as creatures grow more complicated, making them less able to adapt to changing conditions.
. . Led by Yale U evolutionary biologist Gunter Wagner, researchers measured the cumulative effects of genetic mutations in mice. Would tweaking a gene affect many different unrelated traits, thus imposing a "cost of complexity"? Or would the genetic ripple be constrained?
. . The latter, found the researchers: the effects of mutations were indeed multiple, but largely limited to related characteristics. The researchers also found no relationship between effect strength and the number of affected traits. Some scientists have wondered whether these would vary inversely, further slowing the pace of adaptation in complex organisms.
. . "I think the main broader impact of this work is on the evolution-creationism debate", wrote Wagner. "I would say the only intellectually interesting argument that the creationists are using, at least the scientifically more sophisticated ones, is that random mutation can not lead to the evolution of complex organisms. And there are interesting mathematical arguments that have been made to support that. But our results show that organisms found a way around that problem by restricting mutational effects on very narrowly confined parts of the organisms."
Mar 27, 08: David Wentz was snorkeling off Marysville Beach in the St. Clair River last August when what he thought was an odd-looking rock caught his eye. The 3-inch long tooth comes from an extinct species called Carcharodon megalodon, or the "megatooth" shark.
. . The megalodon, which went extinct 2 million years ago, was larger than any building in Port Huron, reaching lengths of more than 60 feet. By comparison, Great White sharks generally are about 20 feet long.
. . Gottfried doesn't think the tooth is from a shark that may have been in the Great Lakes region during two different prehistoric eras, dating back from a half-million years to 300 to 400 million years ago, when it was a "shallow marine environment" filled with sharks, whales and other aquatic life. "I suspect that it was probably carried and dropped by a human inhabitant of the region, either in recent historical times, or perhaps by earlier native people in this area."
Mar 27, 08: The razor-sharp beaks that giant squids use to attack whales —-and maybe even Captain Nemo's submarine-— might one day lead to improved artificial limbs for people. That deadly beak may be a surprise to many people, and has long posed a puzzle for scientists. They wonder how a creature without any bones can operate it without hurting itself.
. . Now, researchers have an explanation. The beak, made of hard chitin and other materials, changes density gradually from the hard tip to a softer, more flexible base where it attaches to the muscle around the squid's mouth. That means the tough beak can chomp away at fish for dinner, but the hard material doesn't press or rub directly against the squid's softer tissues.
. . Frank Zok, professor and associate chair of the department of materials, said he had always been skeptical of whether there is any real advantage to materials that change their properties gradually from one part to another, "but the squid beak turned me into a believer." "If we could reproduce the property gradients that we find in squid beak, it would open new possibilities for joining materials", Zok said. "For example, if you graded an adhesive to make its properties match one material on one side and the other material on the other side, you could potentially form a much more robust bond." Hard medical implants made of metal or ceramic are often imbedded in soft tissues.
Mar 26, 08: A fossil of a new marine crocodile species found in Brazil shows the reptiles survived the extinction of dinosaurs 65 million years ago, researchers said. The discovery of the fossil of Guarinisuchus munizi, dubbed "Sea Warrior", also engendered a new theory on the migration of prehistoric crocodiles from Africa to South and then North America.
. . The 62-million-year-old fossil --3 meters in length-- is part of the Dyrosauridae group, which replaced mosasaurs, or serpentine marine lizards, as the dominant marine predators in the Paleocene epoch.
Mar 26, 08: Tiny foot bones from a 53 million-year-old rabbit ancestor represent the oldest known record of hippity-hoppity mammals and their closest evolutionary relations, according to a new study.
. . The ankle and heel bones were discovered in a coal mine in Gujarat, in west-central India, and recently found by a team of paleontologists to belong to the Lagomorpha, a classification of mammals that includes modern-day rabbits, hares and pikas.
. . It would also be the earliest known mammal identified in India from the Cenozoic era, aka the Age of Mammals, which occurred after the extinction event that wiped out non-avian dinosaurs.
. . The bones, which are four to five times smaller than those of modern-day jackrabbits, resemble pikas in some of their primitive features. But unlike pikas, which don't hop, the bones showed some advanced features that would've made this rabbit-like animal quite a hopper.
Mar 26, 08: A small piece of jawbone unearthed in a cave in Spain is the oldest known fossil of a human ancestor in Europe and suggests that people lived on the continent much earlier than previously believed, scientists say.
. . The researchers said the fossil found last year at Atapuerca in northern Spain, along with stone tools and animal bones, is up to 1.3 million years old. That would be 500,000 years older than remains from a 1997 find that prompted the naming of a new species: Homo antecessor, or Pioneer Man, possibly a common ancestor to Neandertals and modern humans.
. . And, critically, the team says the new one also bears similarities to much-older fossils dug up since 1983 in the Caucasus at a place called Dmanisi, in the former Soviet republic of Georgia. These were dated as being up to 1.8 million years old.
. . "This leads us to a very important, very interesting conclusion", Carbonell said. It is this: that hominins which emerged from Africa and settled in the Caucasus eventually evolved into Homo antecessor, and that the latter populated Europe not 800,000 years ago, but at least 1.3 million years ago.
Mar 26, 08: Scientists have pinned down the fastest-known evolving animal --a "living dinosaur" called a tuatara. The tuatara, Sphendon punctatus, resembles a lizard and is found only in New Zealand. It is the only surviving member of a reptilian order Sphehodontia that lived alongside early dinosaurs and separated from other reptiles 200 million years ago in the Upper Triassic period.
. . To make the estimate of evolutionary speed, researchers recovered DNA sequences from the bones of ancient tuatara. The team found that although tuatara have remained largely unchanged physically over very long periods of evolution, they are evolving --at a DNA level-- faster than any other animal yet examined.
. . Many scientists have thought that molecular evolution would be fastest in animals whose physical form, or morphology, also evolved swiftly. The tuatara finding suggests otherwise, that there is no relationship between the two rates. "Of course we would have expected that the tuatara, which does everything slowly --they grow slowly, reproduce slowly and have a very slow metabolism-- would have evolved slowly." The rate of evolution for Adelie penguins is slightly slower than that of the tuatara.
. . "We want to go on and measure the rate of molecular evolution for humans, as well as doing more work with moa and Antarctic fish. There are human mummies in the Andes and some very good samples in Siberia."
Mar 24, 08: Ants took up farming some 50 million years ago, according to researchers who traced the ancestry of farmer ants. An analysis of the DNA of farmer ants traced them back to an original ancestor.
. . In the last 25 million years, ants have developed different types of farming including the well-known leaf-cutter ants. Leaf-cutter ants don't eat the leaves they collect. Instead, they grow fungus on the leaves and eat the fungus. Only four types of animals are known to farm for food —-ants, termites, bark beetles and, of course, people. All four cultivate fungi.
Mar 24, 08: Scientists have discovered a new species of plant-eating dinosaur in Mexico whose large neck frill and three giant horns helped it attract mates and fight predators on a jungly beach 72 million years ago.
. . Holes in its neck frill would also have set it apart. But scientists say the flamboyant head armor and neck frills were also an important part of courtship rituals, showing dominance with head-butting battles much like modern-day horned animals such as antelope. "That whole section of the head was for sexual display, it was all ornamentation."
Mar 23, 08: Scientists said they had ruled out a key hypothesis to explain Earth's greatest extinction, when 95% of marine species and 70% of land species were wiped out.
. . Dubbed "the Great Dying" or "the mother of all mass extinctions", the catastrophe occurred around 250 million years ago at the end of the Permian era. The event may have unfolded over millions of years, and an increasing number of clues testify to its severity, include the discovery worldwide of eerie, fossilised, mutant plant spores. What is unclear, though, is what caused it.
. . British researchers ruled out a leading theory that the oceans became starved of oxygen and rich with sulphide, causing marine life to die out. Clouds of hydrogen sulphide --the same chemical that comes from rotting eggs-- rose from the seas and, abetted by methane released as a by-product of intense vulcanism, attacked the ozone layer, the stratospheric shield that filters ultraviolet-B light from the Sun. On the ground, life was ravaged, goes this theory. Living things were poisoned by toxic levels of hydrogen sulphide and their DNA was shredded by solar radiation.
. . A team led by David Beerling of the U of Sheffield in England created a two-dimensional computer model of atmospheric chemistry to test this notion. According to their calculations, the lower levels of the atmosphere in the tropics would have acted as an oxidising buffer, preventing the hydrogen sulphide from seriously damaging the ozone layer. "These gases seem unlikely to be the cause of coincident terrestrial biotic extinctions."
. . Other theories still in the arena include an impact, or series of impacts, by an planetisimal, similar to the event believed to have wiped out the dinosaurs some 62 million years ago. A "deep impact" of this kind would have generated a dust storm that smothered the planet, obscuring the Sun and shrivelling vegetation.
Mar 21, 08: Scientists who conducted the most comprehensive survey to date of New Zealand's Antarctic waters were surprised by the size of some specimens found, including jellyfish with 12-foot tentacles and 2-foot-wide starfish.
. . A 2,000-mile journey through the Ross Sea has also potentially turned up several new species, including as many as eight new mollusks. Robertson added that of the 30,000 specimens collected, hundreds might turn out to be new species.
Mar 20, 08: Sexual reproduction may be nearly as old as animal life itself, according to researchers who discovered a new species of organism that lived 540 million years ago. The tube-like creatures called Funisia dorothea anchored themselves in abundant flocks onto the shallow, sandy seabed of what is now the Australian outback.
. . Nothing appears to have evolved yet to eat them, so they lived peaceful lives, reproducing sexually at times and by asexual methods such as budding at other times. They lived in dense groups of similar size and aged animals, like mussels and oysters do. "It is common modern ecological strategy, and these guys were doing it in the earliest animal ecosystems on this planet", she said. "We think of these strategies as having been in response to competition and in response to predation."
. . But there is no evidence of predators. Nothing had yet evolved with teeth or even bones. Multicellular animal life is believed to have arisen around 600 million years ago.
Mar 20, 08: A nearly six-million-year-old thigh bone may provide some of the earliest evidence for human ancestors walking on two legs. New measurements of the bone, discovered in Kenya in 2000, confirm that the hip and upper leg were adapted to walking upright, researchers report.
. . The bone is from an early hominin called Orrorin tugenensis. Anthropologists had speculated that O. tugenensis could walk upright but are divided about its place in the evolution of modern humans.
Mar 20, 08: Scientists have discovered a new, fourth, mode of sight in a most unusual creature: a primitive marine crustacean known as the mantis shrimp. Until now, it was believed that animals could see only the intensity, color and --in a few species-- the linear polarization of light.
. . But in a study published today, researchers showed that the mantis shrimp, a fancifully nicknamed stomatopod whose unique evolutionary path began some 400 million years ago, perceives what's known as circular polarized light. They are the first organisms to demonstrate this ability.
. . Linear polarization refers to light with photons traveling along parallel, up-and-down wavelengths. By contrast, circular polarized light -- CPL for short -- has photons traveling in parallel, rotating wavelengths. It occurs rarely in nature but is widely used in high-tech communications. Researchers say that understanding the eyes of mantis shrimps could help engineers design better CPL systems.
. . CPL's tightly rotating configuration reduces data losses during transmission. (When an antenna sports something that looks like a tightly wound spring, that's for CPL.) It could someday be used in mobile phones --invisible to our eyes, but not to the machines that detect it.
. . Human applications aside, the discovery of a new type of sight is a landmark unto itself, and the mantis shrimp is an odd but deserving history maker. "Since they branched off from animals so early, their evolution took them in unique directions." "We used to call them shrimps from Mars, because their biology is so different from any other animal."
. . Like insects and other crustaceans, mantis shrimps possess compound eyes composed of thousands of rows of light-detecting units called ommatidia. These are especially refined in mantis shrimps, containing a mix of photoreceptors and filters that let them see 100,000 different colors -- 10 times more than can be detected by humans.
Mar 20, 08: Gas-belching volcanoes may be to blame for a series of mass extinctions over the last 545 million years, including that of the dinosaurs, new evidence suggested. A series of eruptions that formed the Deccan Traps in what is now India pumped huge amounts of sulfur into the atmosphere 65 million years ago, with likely devastating repercussions for the Earth's climate, scientists said.
. . Gigantic eruptions, forming so-called "flood basalts", are one of two leading explanations for a series of mass extinctions that have killed off species periodically throughout history. The other theory involves planetisimal impacts --generally considered the prime suspect.
. . There have been doubts about the killing power of volcanoes because, until now, researchers have struggled to measure just how much toxic gas would have been released. But after finding rare inclusions of glass in the Deccan rock, a British-based team has found vital preserved information about its original gas content.
. . They concluded that the massive of amounts of both sulfur and chlorine released would probably have had a "severe" environmental impact. "It certainly bolsters the case, though it doesn't prove it."
. . The volcanoes may have spewed 10 times as much sulfur into the atmosphere every year as humans have done recently by burning coal in power stations and through other industrial activities. The result would have been widespread acid rain and aerosols of sulfuric acid in atmosphere, cooling the surface of the Earth and upsetting normal patterns of circulation.
Mar 19, 08: Birds start singing in the spring because of a biological response to longer days, researchers said. When birds are exposed to light for longer periods, certain brain cells trigger a series of hormonal reactions telling them to find a mating partner, which they do by singing.
. . Genes in cells on the surface of the brain switched on when the birds received more light and began releasing a thyroid-stimulating hormone. The genes activated 14 hours after dawn on the first day of sufficient length, the researchers said.
. . The findings could also one day lead to better treatments for infertility because humans have the same cells in the same part of the brain. Vitamins known as folates that prevent birth defects when consumed by women also help to keep men's sperm normal, researchers reported.
. . Men who took folic acid supplements and who ate folate-rich foods such as leafy greens had fewer abnormal sperm. Specifically, the men had fewer abnormal sperm in which a chromosome had been lost or gained, known as aneuploidy. Sperm aneuploidy can cause failure to conceive, causes up to a third of miscarriages and causes children to be born with Down's syndrome and other rare chromosomal syndromes. Folic acid can prevent nerve damage in growing babies and is so important that it is added to flour, rice and other staples in many countries.
. . Eskenazi's team said estimates suggest that between 1% and 4% of sperm in a healthy man have some type of aneuploidy but this varies from man to man.
Mar 18, 08: Using tiny brushes and chisels, workers picking at a big greenish-black rock in the basement of North Dakota's state museum are meticulously uncovering something amazing: a nearly complete dinosaur, skin and all.
. . Unlike almost every other dinosaur fossil ever found, the Edmontosaurus named Dakota, a duckbilled dinosaur unearthed in southwestern North Dakota in 2004, is covered by fossilized skin that is hard as iron. It's among just a few mummified dinosaurs in the world. It will take a year, maybe more, to uncover it. "The actual length would be about 9.5 meters."
Mar 14, 08: If there's something strange in the neighborhood ...clone yourself. That's the philosophy of sand dollar larvae, which copy themselves when they sense predators are near. Scientists exposed 4-day-old sand dollar larvae to fish mucus, a sign that danger is close. They found that the larvae created clones of themselves within 24 hours. "It's the first time we've seen anything clone itself in response to cues that predators are near", said researcher Dawn Vaughn.
. . Sand dollar larvae are tiny globs that float along with plankton in the sea, an easy target for hungry fish. When they are 6 weeks old, they settle to the seafloor and eventually become adult sand dollars with their distinctive petal-patterned shells.
. . After being exposed to fish mucus, the larvae formed embryo-like buds that eventually detached and developed into new, genetically-identical larvae that were much smaller than the originals. The parent larvae were left smaller, too, measuring about half their beginning size. Larvae that were not exposed to the fish mucus did not clone themselves.
. . The scientists think cloning may provide a double benefit to larvae facing danger. By doubling themselves, they have a second chance to ensure their genetic information survives even if one larva gets eaten. Additionally, being smaller may be beneficial to larvae trying to hide from fish.
. . Cloning had previously been observed in sand dollar larvae in response to a greater availability of food or favorable temperatures.
Mar 13, 08: Alligators can stealthily maneuver through the water leaving nary a ripple, despite having neither fins nor flippers like other adept swimmers. Instead, they use special muscles to shift the position of their lungs, U.S. researchers said.
. . They said American alligators use their diaphragm, pelvic, abdominal and rib muscles to change their center of buoyancy, forcing the lungs toward the tail when they dive, toward the head when they surface, and sideways to roll.
Mar 13, 08: Nearly all of today's Native Americans in North, Central and South America can trace part of their ancestry to six women whose descendants immigrated around 20,000 years ago, a DNA study suggests. Those women left a particular DNA legacy that persists to today in about about 95% of Native Americans, researchers said.
. . The finding does not mean that only these six women gave rise to the migrants who crossed into North America from Asia. The women lived between 18,000 and 21,000 years ago, though not necessarily at exactly the same time.
Mar 12, 08: Most days, Moko the bottlenosed dolphin swims playfully with humans at a New Zealand beach. But this week, it seems, Moko found his mojo. Witnesses described Wednesday how they saw the dolphin swim up to two stranded whales and guide them to safety.
. . Before Moko arrived, rescue workers had been working for more than an hour to get two pygmy sperm whales, a mother and her calf, back out to sea after they were stranded. The whales restranded themselves four times on a sandbar slightly out to sea from the beach, about 300 miles northeast of the capital, Wellington. It looked likely they would have to be euthanized to prevent a prolonged death.
. . "They kept getting disorientated and stranding again", said Smith, who was among the rescuers. "They obviously couldn't find their way back past (the sandbar) to the sea." Then along came Moko, who approached the whales and appeared to lead them as they swam 200 yards along the beach and through a channel out to the open sea. "Moko just came flying through the water and pushed in between us and the whales."
Mar 11, 08: Researchers have found that monkeys combine calls to make them meaningful in the same way that humans do. It is hoped the St Andrews U study will provide fresh insights into the evolution of human language.
. . The researchers recorded the alarm calls of putty-nosed monkeys in Nigeria and noticed them combining noises to apparently convey different meanings. "At some point, according to the theory, it became more economical for humans to combine existing elements of communication, rather than adding new ones to a large repertoire. This is based on the notion that signals would be combined only once the number of them had grown sufficiently. "Our research shows that these assumptions may not be correct."
. . In 2006, researchers from St Andrews found that monkeys produced different series of alarm calls in order to distinguish which predator they are responding to. The latest research provides evidence that the various calls may contain at least three types of information --the event witnessed, the caller's identity, and whether he intends to travel, all of which were recognized by other monkeys.
Mar 6, 08: Seth Shostak: Recent investigations by astrobiologists in Australia and Norway strongly suggest that life had gained a foothold on Earth more than 3.5 billion years ago, when the watery oceans of our planet were first safe for habitation. Astrobiologists are asking how this happened, and investigating the role played by the clouds of carbon compounds churned up in nearby space, and rained onto our planet while it was forming. Was this natural fertilizer essential, or merely supplemental?
. . The facts are that DNA and RNA are enormously complex molecules, and their appearance by chance seems, to some, improbable. But researchers have pointed to natural structures, such as clays, that could act as catalysts to speed the start of life. We still don't know for sure how life first began on Earth, but this highly fecund area of research could bear sweet fruit for astrobiology, either telling us that life is so improbable as to be nearly miraculous, or so inevitable as to be trivially common.
Mar 5, 08: A species of plant found in cities has evolved rapidly in order to adapt to the challenges of surviving in the concrete jungle, a study suggests. Crepis sancta growing in urban areas produces heavy seeds that fall to the ground rather than lighter seeds that are dispersed by the wind. Wind-blown seeds are less likely to germinate because most end up on concrete surfaces, scientists say.
. . Researchers estimate that the change in the way the plant disperses its seeds has taken place in as little as five to 12 generations (five to 12 years).
. . Co-author Pierre-Oliver Cheptou said the team was surprised by the speed of the change. "Logic would assume that this sort of evolutionary trait would develop more slowly, which is probably the case in less fragmented situations."
Mar 5, 08: Scientists have discovered that moths can remember odors they were exposed to as caterpillars.
Mar 5, 08: Scientists have found an Antarctic fish that hibernates to conserve energy during the long southern winters. The cod Notothenia coriiceps enters a dormant state, similar to hibernation in land animals like hedgehogs, British scientists said.
. . Researchers already knew Antarctic fish had antifreeze chemicals in their blood and their ability to effectively put themselves "on ice" is another remarkable adaptation to an extreme environment.
Mar 4, 08: Smells so irritating they make you cough or gag may act upon a single type of cell in the nose that senses caustic chemicals and warns the brain of potential danger, U.S. researchers said.
Mar 4, 08: He was the Albert Einstein of his time --aside from the fact that this long-extinct critter weighed about an ounce (28 grams), measured three inches long and munched on bugs and berries.
. . A U.S. scientist has unearthed the remains of the earliest-known primate to live in North America. In doing so, he figured out the path these ancient representatives of the mammalian group that includes lemurs, monkeys, apes and people must have taken to reach this part of the world. It lived 10 million years after the dinosaurs.
. . Based on a group of teeth from a teeny primate unearthed in Mississippi dating to 55.8 million years ago, paleontologist Christopher Beard said the species likely scampered over a now-vanished land bridge connecting Siberia to Alaska. The tiny immigrant is called Teilhardina magnoliana.
. . "Primates have nails on their digits instead of claws. Primates have eyes that face forward and give us stereoscopic vision, instead of having eyes on the side of our heads like a dog or a horse. Primates almost always have relatively larger brains than other mammals", Beard said.
. . "It's a small, primitive primate. In some ways, it would have looked more like a teeny, tiny monkey than it would have looked like a small lemur",Beard said, noting that it lived more than 10 million years before the first primitive monkeys. It was not ancestral to New World monkeys, but might have been in the lineage leading to a type of primitive primate known as Tarsiers that still lives in southeast Asia.
. . The fossil teeth were dug up near Meridian, Mississippi, close to the former coastline of the Gulf of Mexico. They are older than any primate fossils from Europe, he said, suggesting that rather than migrating from Europe to North America, this primate might have ventured the other way around.
Mar 3, 08: Scientists keep finding more similarities between humans and chimps. They share most of our genes, they seem to be able to handle tools, and they grasp some English pretty well, too.
. . Now, researchers have found that we share a similar brain pattern when communicating. Broca's area, located in the part of the human brain known as the inferior frontal gyrus, has been shown to be critical for human speech and sign language. When a person speaks, or even plans to say something, this region lights up with activity. "This is the first time someone has measured activity in that area in chimp brains."
. . They used a PET scan to image activity in the brains of three chimps after doing two tasks. In one, the chimps asked for food by gesturing and vocalizing --making grunts and other noises. In another, they passed rocks out of their cages in exchange for food, as they had been taught to do before. The scientists found that Broca's area was activated in the chimps' brains after making gestures and vocalizing, but not after the rock task, signaling that this brain region is particularly tied to communication.
. . The finding narrows the gap between humans and chimpanzees a little bit more. The major differences come down to ones of degree, not of kind." Human and chimpanzee genomes differ by only 1.5 to 5 percent.
. . Taglialatela also said chimps do not have the self-control humans do. Where people often censor their words and actions to fit a social situation, chimps generally act on impulse. If they are hungry, they will ask for food; if they are angry at another chimp, they might take a swat at him.
Mar 3, 08: Darwin maintained that the domesticated chicken derives from the red jungle fowl. That seems at least partly true, but new research from Uppsala U now shows that the wild origins of the chicken are more complicated.
. . The researchers mapped the genes that give most domesticated chickens yellow legs and found the genetic heredity derives from a closely related species, the gray jungle fowl, tho most of the genes in domesticated fowls come from the red jungle fowl.
. . The scientists believe that the same gene may well be of significance in explaining the pink color of the flamingo, the yellow leg color of many birds of prey, and the reddish meat of the salmon. These characteristics are all caused by carotenoids. The gene may also influence the skin color of humans to some extent.
Mar 2, 08: Two University of Virginia researchers believe that humans are genetically predisposed to be deathly afraid of snakes. She believes it's because snakes would have posed a significant threat to our ancestors, so a fear of snakes remains hardwired into human brains today.
. . They asked half of the people to find the single image of a snake among non-threatening pictures of caterpillars, flowers or frogs. The second group was told to find the single photo of a single non-threatening item among eight images of snakes. The researchers found that adults and children were much faster at discovering snakes than they were at locating non-threatening flora or fauna. The finding that children saw the snakes as rapidly as adults is particularly fascinating, LoBue said.
. . She has found similar results when testing for an innate fear of spiders. Much like snakes, some spiders would have posed a deadly threat to pre-humans.
Feb 28, 08: A trawl through the genes of white people in Utah and Yoruba people in Nigeria shows a significant number of differences that can explain why some groups respond differently to drugs than others. The findings also suggest that genes underlie some susceptibility to diseases in a general population.
. . What the study does not show, the researchers stress, is that any of these differences are necessarily racial. But they are a first step toward a day when medical care may be tailored not only for individuals, but for entire groups.
. . While the differences are not dramatic, some are clear enough to explain different reactions to drugs and differing susceptibility to disease. For instance, they found a mutation in a gene called CTTN, which is linked with cancer, in the Utah people, and seldom or never in the Yoruba group. Changes in a certain part of the gene are often found in breast cancer and in squamous cell carcinomas of the head and neck.
Feb 28, 08: Bats stay aloft by employing an aerodynamic trick previously thought unique to insects, researchers said. Using a wind tunnel to study the wake bats leave as they fly, they found that a tiny cyclone of air over each wing called a leading edge vortex provided as much as 40% of the lift required.
Feb 28, 08: Tiny twitches of their whiskers allow rats to "see" in the dark, helping them to find their way home or back to a particularly savory garbage pile.
Feb 27, 08: A fossilized "sea monster" unearthed on an Arctic island is the largest marine reptile known to science, Norwegian scientists announced. The specimen was found on Spitspergen, in the Arctic island chain of Svalbard, in 2006. The Jurassic-era leviathan is one of 40 sea reptiles from a fossil "treasure trove" uncovered on the island.
. . The immense creature would have measured 15m. "A large pliosaur was big enough to pick up a small car in its jaws and bite it in half." The Svalbard specimen is 20% larger than the previous biggest marine reptile --another massive pliosaur from Australia. "The flipper is 3m long with very few parts missing."
. . "One hundred and fifty million years ago, Svalbard was not so near the North Pole, there was no ice cap and the climate was much warmer than it is today."
Feb 27, 08: Advice on how to score with the ladies would probably never include the strategy that works best for at least one species of male spider: playing dead. Not all male nursery web spiders looking for a little arachnid sex adopt this technique, but those that do more than double their chances of hitting the jackpot, according to new study.
. . All the males sought to attract partners by offering a gift of food, held in the mouth. But the ones that lay flat and motionless --even if meant getting dragged about by a female that had latched onto the victuals-- wound up in a much better position, as it were, to engage in sexual activity. The hapless males that tried the direct approach wound up keeping the free meal but not getting what they were really after. Males that played dead were also allowed to copulate longer than males that did not, ensuring more eggs could fertilized.
. . Playing dead is a well-known defence mechanism in nature, but this is apparently the first time such behavior has been observed as a strategy for obtaining sexual favors.
Feb 26, 08: The first 30,000 pages have been unveiled of a vast encyclopedia which aims to catalog every one of our planet's 1.8 million species. The immense online resource is designed to greatly enhance our understanding of the world's diminishing biodiversity. The creators of the database say it could have an impact on human knowledge comparable to that which followed the microscope's invention in the 1600s. It is designed to be used by everyone from scientists to lay readers.
. . The Encyclopedia of Life --described as the "ultimate field guide"-- is to encompass all six kingdoms of life, and even viruses --which many researchers do not consider to be living organisms.
Feb 25, 08: When marauding Vikings decided to settle down they usually "went native", marrying local girls and blending in. Invading honey bees may be doing the same. The invasion of new bee populations has attracted attention in recent years with the spread of so-called Africanized, or "killer bees" moving north from South America.
. . When a new strain of bees invades a region already populated by honey bees, they interbreed and gain benefits from the genes of their predecessors, researchers report. Whitfield's team found that when invading bees were interbreeding with those already present, the combined genes were not just joined randomly.
. . When the African honey bees mated with the western European honey bees that had been in South America for centuries, one might expect that the hybrid offspring would randomly pick up both the functional and nonfunctional parts of the genome, he said. "But actually what we found was there was a preference for picking up functional parts of the western European genome over the nonfunctional parts."
Feb 25, 08: Rules that allow only the catching of larger fish may encourage their replacement with slower growing, more timid varieties. That, at least, is the concern of researchers who studied test populations in two artificial lakes and report their findings.
. . It's the fast-growing more aggressive fish that tend to get caught, removing them from the breeding pool. That leaves reproduction up to slower-growing fish, who are more timid. "This will cause evolution to slow growth rates and slow the rate of recovery for fished populations, and could explain why fisheries tend not to rebound in the manner we expect after we reduce harvest or close a fishery", he said.
. . "What surprised me was how fast it occurred", Biro said. He said the largest catch occurred on the first day of fishing. Biro and his colleague stocked two lakes in western Canada with different types of rainbow trout —-one type was known to be aggressive in seeking food and to grow rapidly, while the other grew more slowly and tended to take fewer risks in foraging. They set gillnets in the ponds over five days, moving them each day, and caught 50% of the stocked fast-growing fish but just 30% of the more cautious ones.
Feb 21, 08: Scientists at Stanford U in California combed through the genes of 938 people from 51 places, looking at 650,000 DNA locations in each person. "This is the highest resolution look at population genetics that has been done to date."
. . The study revealed similarities and differences among various populations. People indigenous to Siberia have strong genetic links to native peoples in the Americas, according to a study further supporting the theory that humans first entered the Americas over a land bridge across the Bering Strait.
. . One striking finding was the genetic similarities between the Yakut people, who live in Siberia, and several native populations from Mexico, Central America, Colombia and Brazil, the researchers said. These include the Maya in Central America and the Surui and Karitiana in Brazil. The scientists also were able to detect genetic differences between northern and southern Chinese populations as well as variations within the Bedouin populations of the Middle East.
Feb 21, 08: Fossil hunters have found the remains of ancient mammals that were related to today's rabbits and hares. The 53-million-year-old specimens consist of small ankle bones unearthed in Gujarat, central India. They belong to early examples of an animal group called lagomorphs, which today comprises hares, rabbits and a hamster-like animal called a pika.
. . The study shows that the lagomorphs were already distinct from other mammals by 53 million years ago. Some of their early evolution must have taken place while India was in the process of colliding with Asia.
. . An explosion in the diversity of mammals has been linked to a sharp bout of global warming about 55 million years ago. The causes are not fully understood; but rising temperatures may have caused a sudden release from the sea floor of ice-trapped methane --a potent greenhouse gas - which contributed to greenhouse warming.
Feb 21, 08: The sudden appearance of vertebrates 600 million years ago has been a bit of a mystery to evolutionary biologists. New research suggests the development of backbones may be tied to microRNA.
Feb 21, 08: A hormone is the secret behind the unusual ability of young swallowtail caterpillars to disguise themselves as bird droppings and then copies of the leaves they live on before becoming butterflies, Japanese researchers found.
Feb 21, 08: Scientists have found the fossil of a new herbivorous dinosaur species that stood five meters high and lived 60 million years ago. The large long-necked sauropod was around 15 meters long.
Feb 20, 08: Two big genetic studies confirm theories that modern humans evolved in Africa and then migrated through Europe and Asia to reach the Pacific and Americas. The two studies also show that Africans have the most diverse DNA, and the fewest potentially harmful genetic mutations. One of the studies shows European-Americans have more small mutations, while the others show Native Americans, Polynesians and others who populated Australia and Oceania have more big genetic changes.
. . The studies paint a picture of a population of humans migrating off the African continent, and then shrinking at some point because of unknown adversity. Later populations grew and spread from this smaller genetic pool of founder ancestors --a phenomenon known as a bottleneck.
. . People of African descent are the most genetically diverse, followed by people from the Middle East, and then Asians and Europeans. Native Americans resemble one another the most on a DNA level. The study also found it is sometimes possible to trace a person's ancestry to a small group within a geographic region.
Feb 20, 08: The seeds of the "suicide palm", a newly discovered and extremely rare palm tree, have arrived in Britain for urgent study and conservation, the Royal Botanical Gardens at Kew said. About 1,000 of the Tahina spectabilis tree's grape-sized seeds, harvested by local villagers, arrived at Kew's Millennium Seed Bank earlier this week. We have also sent seeds to 11 botanical gardens around the world, where we hope the palm will thrive."
. . The tree, whose nickname stems from its habit of flowering itself to death once every half century, was discovered only recently on the island of Madagascar. Only about 100 examples are known to exist of the tree, which grows to more than 18 meters high over a period of 50 years before bursting into bloom just once with hundreds of tiny flowers for pollination and then dying.
. . It had not previously been noted despite being Madagascar's most massive palm tree, which can even be spotted on Google Earth. It towers more than fifty feet above the ground and has fan-shaped leaves that, at fifteen feet in diameter, rank among the largest of any flowering plant.
Feb 19, 08: Florida education officials voted to add evolution to required course work in public schools but only after a last-minute change depicting Charles Darwin's seminal work as merely a theory. [ Anyone who sez "merely a theory" has no idea what the word means. jkh]
Feb 19, 08: A team of U of Virginia researchers is working to increase the drought- and disease-resistance of the black-eyed pea [a bean], a staple of the diets of roughly 200 million people in west and central Africa.
Feb 19, 08: Scientists studying Antarctic waters have filmed and captured giant sea creatures, like sea spiders the size of dinner plates and jelly fish with six meter tentacles. A fleet of three Antarctic marine research ships returned to Australia this week ending a summer expedition to the Southern Ocean where they carried out a census of life in the icy ocean and on its floor, more than 1,000 meters below the surface. Some 25% of the sealife chronicled was previously unknown.
. . "Gigantism is very common in Antarctic waters --we have collected huge worms, giant crustaceans and sea spiders the size of dinner plates. In some places every inch of the sea floor is covered in life. In other places we can see deep scars and gouges where icebergs scour the sea floor as they pass by."
. . The Australian Antarctic Division expedition will help scientists monitor how the impact of environmental change in Antarctic waters, such as ocean acidification caused by rising atmospheric carbon dioxide levels, will make it harder for marine organisms to grow and sustain calcium carbonate skeletons. "It is predicted that the first effects of this will be seen in the cold, deep waters of Antarctica", said Riddle. "What we saw down there were vast coraline gardens based on calcareous organisms and these are the ones that could really be lost in an increasingly acidic ocean."
Feb 18, 08: A frog the size of a bowling ball, with heavy armor and teeth, lived among dinosaurs millions of years ago. Like those modern frogs, Beelzebufo had a wide mouth and powerful jaws, plus teeth. Skull bones were extremely thick, with ridges and grooves characteristic of some type of armor or protective shield.
. . Scientists announced the discovery in northwestern Madagascar of a bulky amphibian dubbed the "devil frog" that lived 65 million to 70 million years ago and was so nasty it may have eaten newborn dinosaurs. This brute was larger than any frog living today and may be the biggest frog ever to have existed, according to paleontologist David Krause.
. . Its name, Beelzebufo ampinga, came from Beelzebub, the Greek for devil, and bufo --Latin for toad. Ampinga means "shield", named for an armor-like part of its anatomy. Beelzebufo (pronounced bee-el-zeh-BOOF-oh) was 39cm long and weighed an estimated 4.5 kg. It was powerfully built and possessed a very wide mouth and powerful jaws.
. . Even though it lived far away, Beelzebufo appears to be closely related to a group of frogs that live today in South America, the scientists said. They are nicknamed "Pac-Man" frogs due to their huge mouths. Some have little horns on their heads, and the scientists think Beelzebufo also may have had horns --a fitting touch for the "devil frog."
. . Beelzebufo lived during the Cretaceous Period at the end of the age of dinosaurs, which went extinct along with many other types of animals 65 million years ago. It lived in a semi-arid environment and may have hunted like its modern-day relatives, which camouflage themselves and jump out at prey.
. . Beelzebufo is not the largest amphibian ever to have lived. Many reached truly astounding dimensions, such as the crocodile-like Prionosuchus that grew to an estimated 30 feet during the Permian Period, which ended about 250 million years ago.
Feb 16, 08: A bizarre relationship between a gecko and a sap-sucking insect has been caught on camera for the first time. The day gecko, which lives in the forests of Madagascar, has been recorded begging a bug for its dinner. The lizard repeatedly nods its head at the insect, called a plant hopper, until it flicks over small balls of honeydew for the gecko to dine upon.
. . It is not yet understood why the insect so willingly offers up honeydew at the lizard's behest. Some believe that the presence of the hungry geckos may keep other predators away from the insect.
Feb 15, 08: Genes that helped early humans adapt to cold climates may be driving metabolism-related diseases such as obesity or diabetes in many countries, U.S. researchers said. They found a strong correlation between climate and genetic adaptations that influence the risk of metabolic syndrome, a group of related disorders such as obesity, high cholesterol, heart disease and diabetes.
. . Anthropologists have long made the case that certain traits such as differences in skin pigmentation reflect early human migration from equatorial Africa to cooler climates --for instance, the link between paler skin and an ability to synthesize vitamin D from sunlight. "They had to develop genetic variants that made them more efficient in terms of energy metabolism and that made them more able to cope with cold climates by increasing their rate of thermogenesis --the ability to generate and maintain heat", she said.
. . The research team picked 82 genes associated with energy metabolism and looked to see if there were any correlations with climate. They studied variations in 1,034 people from 54 populations. They saw several clusters of different genetic variations related to metabolic syndrome in colder climates.
. . One gene, the leptin receptor, is increasingly common in areas with colder winters. Leptin is important to appetite and weight gain --something people need no help with in modern times.
Feb 14, 08: Fossils from two newly discovered meat-eating dinosaurs that lived in the Sahara Desert 110 million years ago paint a fearsome picture of life in Africa's Cretaceous period, which appears to have been teeming with unusual carnivores.
. . U of Chicago paleontologist Paul Sereno unearthed Kryptops palaios, a short-snouted, hyena-like beast, and Eocarcharia dinops, a shark-toothed, bony-browed killer in a 2000 expedition. Both were about 25 feet in length --and on the prowl for meat. "These are two of three that we dug up. To have three large predators in this area is really extraordinary", said Sereno. The third, the fish-eating, sail-backed Suchomimus or "crocodile mimic", was found in 1997. "They were also living alongside a 12-meter crocodile, SuperCroc. They lived in a vicious time", he said.
. . Kryptops was a scavenger and had a uniform series of relatively pointy teeth and a short snout. "The idea was that the animal was sticking its head into carcasses", he said. Eocarcharia, or "dawn shark", is known for its blade shaped teeth and bony brow. "The teeth are very narrow side-to-side. They are blade-shaped for cutting. This animal specialized in capturing live prey and severing limbs. It was definitely a sabotage attacker, waiting for an opportunity to jump at something", Sereno said.
Feb 13, 08: When Guy Hoelzer runs computer simulations of organisms living in the modeling equivalent of a featureless plain, he sees them break into different species --even though there's no reason for natural selection to take place. That preliminary but tantalizing finding hints at some larger phenomenon driving the mechanisms of neo-Darwinian evolution. Hoelzer thinks the phenomenon is self-organization: combine energy with complex networked interaction and order will emerge.
Feb 13, 08: A fossil found in Wyoming has apparently resolved a long-standing question about when bats gained their radar-like ability to navigate and locate airborne insects at night. The answer: after they started flying. The discovery revealed the most primitive bat known, from a previously unrecognized species that lived some 25.5 million years ago. The creature was unusual for having a claw on all five fingers rather than just one or two.
. . Its skeleton shows it could fly, but that it lacked a series of bony features associated with "echolocation". Until now, all the early known fossil bats showed evidence of both flying and echolocating, so they couldn't reveal which ability came first.
. . The early bat's wingspan was nearly a foot, just a bit smaller than that of today's big brown bat, she said. Its teeth show it ate insects, which it evidently plucked off surfaces after seeing, smelling or hearing them, she said. Simmons said she suspects the bat was active at night, but she noted there's no evidence for that.
Jan 03, 08: Bees Only. By conceiving of evolution as acting upon entire populations rather than individual organisms can we understand eusociality --the mysterious, seemingly "altruistic" behaviors exhibited by insects who forego reproduction in order to care for a colony's young. So says Edward O. Wilson, the legendary sociobiologist, environmentalist and entomologist, in an article published in the January issue of Bioscience.
. . Observed in some species of ants, bees and wasps, eusociality has perplexed researchers unable to explain --in traditionally evolutionary terms, at least-- how entire insect castes could have evolved not merely to refrain from reproducing, but to care for genetically distant larva.
. . He explained the phenomenon as one of kin selection: evolution didn't act on individuals, but groups of closely related individuals. However, says Wilson, new findings make kin selection an incomplete explanation. He points to the emergence of eusociality in insect species that don't possess haplodiploidy, a mechanism of sex selection that makes females more genetically similar to their sisters than their offspring. If kin selection drove eusociality, then it should have emerged primarily in these species. Moreover, most haplodiploid species are not eusocial.
. . Wilson thinks eusociality evolved as a group-level adaptation for out-competing other insect colonies for food: with some colony members devoted to protecting eggs and larva, others could forage farther abroad. All that's needed to take this evolutionary step is the rise of a gene --or system of genes-- that makes workers want to stay home and help rather than leave the colony and reproduce elsewhere.
. . "While only 2% of known insect species are eusocial", writes Wilson, "these species comprise most of the insect biomass." While one has to be careful in drawing early conclusions and then applying them to people, it's clear that in some ways this cooperative system, so much more subtle than the classically self-centered Darwinian ideal, is extraordinarily successful.
. . So with all necessary caveats against reductionism and misappropriation, we can ask: should human societies conceive of themselves in terms of group-level selection? Have we already developed aspects of eusociality? And --just to make matters really interesting-- could non-reproducing humans, such as (most) gays and lesbians, as well as heterosexuals who choose not to have kids, actually be a manifestation of this emergent eusociality?
. . Citing eusociality in defense of any lifestyle choice, even theoretically, could backfire: it implies a subservience of individual well-being to the greater good. But at least it suggests that certain unorthodox lifestyles might not be so "unnatural" after all.
. . Eusociality is a term used for the highest level of social organization in a hierarchical classification. The term "eusocial" was introduced in 1966 by Suzanne Batra and given a more definitive meaning by E. O. Wilson. It was originally defined to include those organisms (originally, only invertebrates) that had certain features:
. . 1. reproductive division of labor (with or without sterile castes)
. . 2. overlapping generations
. . 3. cooperative care of young
The lower levels of social organization, subsociality, were classified using different terms, including presocial, subsocial, semisocial, parasocial and quasisocial. The only mammalian examples are the naked mole rat and the damaraland mole rat.
. . this last From Wikipedia
Feb 13, 08: A growing number of scientists do say that neo-Darwinian evolution doesn't explain certain jumps in biological complexity: from single-celled to multicellular organisms, from single organisms to entire communities. The jumps --saltations, in complexity parlance-- appear to be non-linear emergent phenomena, the result of networked interactions that produce self-organization at ever higher levels. From this perspective, Darwinian evolution is a mechanism of a higher universal law, perhaps even a variant on the second law of thermodynamics.
. . Carl Woese, a titan of 20th century microbiology, with colleague George Fox, reorganized the organismal kingdom from five branches to three. Woese's experience with bacteria led him to look for an evolutionary framework larger than that provided by Darwin and his intellectual descendants. Bacteria -- which may account for up to half of Earth's biomass -- swap genes without reproducing; with millions residing in a teaspoon of seawater, Woese sees them in terms of networked communities rather than individual cells, and interprets their evolutionary history as driven by the non-linear self-organization that's now being studied at all biological scales.
Feb 11, 08: As pterodactyls go, it was small, toothless and had unexpectedly curved toes —-yet scientists are welcoming their new find as another piece in the puzzle of ancient life. Pterodactyls are best known from giant examples of the ancient flying reptiles, and most specimens have been uncovered in coastal areas. It was dubbed Nemicolopterus crypticus —-hidden flying forest dweller --sparrow sized, and lived essentially in the trees.
. . When first uncovered, the researchers thought it was a baby. The skull was not fully fused, meaning it was not yet an adult, but the ends of the bones were developed, so it was not a hatchling either. It had a wingspan of less than 30cm (1ft). The legs and feet of Nemicolopterus had attachments for muscles indicating that it could grasp limbs, and unlike most pterodactyls, it lacked teeth. They speculated it might have eaten insects. The nearly complete articulated skeleton was unearthed in fossil beds from north-eastern China.
. . The 120-million-year-old specimen contains several unique anatomical features that distinguish it from other pterosaurs. Some of the foot bones are curved in a way not seen in other members of this reptile group. This, say the authors, indicates the pint-sized creature spent much of its time living in the trees.
. . Pterosaurs lived alongside the dinosaurs, from 228 million years ago to 65 million years ago. They were the first vertebrates to evolve winged flight. One pterosaur known as Quetzalcoatlus was enormous, sporting a wingspan of up to 11m, placing it among the largest flying animals ever.
Feb 10, 08: Whether it is heavier birth weights, amplified testosterone levels or simple, hair-raising high jinks, boys seem to take an extra toll on the women who gave birth to them. And by poring over Finnish church records from two centuries ago, Virpi Lummaa of the U of Sheffield in England can prove it: sons reduce a mother’s life span by an average of 34 weeks.
. . More recently, Lummaa and her colleagues have been studying how sons are not just tough on their mothers but also hard on their siblings. Those born after a son were physically slighter, had smaller families and generally had a greater chance of dying from an infectious disease.
. . This phenomenon is particularly evident in twins where one is male and the other is female. Of 754 twins born between 1734 and 1888 in five towns in rural Finland, girls from mixed-gender pairs proved 25% less likely to have children, had at least two fewer children, and were about 15% less likely to marry than those born with a sister.
. . The reason that the female half suffers, Lummaa speculates, is because of testosterone exposure in the womb. Researchers have seen such hormonal influence in other animals, including lab rats and cows. When a cow has mixed-sex twins, the female is occasionally born sterile because of testosterone influence.
. . Whatever the cause, there is no question of the outcome: mothers of opposite-sex twins end up with 19% fewer grandchildren than moms of same-sex twins, meaning evolution would seem to favor the latter.
. . Lummaa and her colleagues have also begun to parse the Finnish records to understand grandparents and the evolutionary conundrums they pose. Her group’s previous research has shown that grandmothers provide direct aid in ensuring the survival and reproduction of their grandchildren. The same records revealed, however, no such benefit from fathers and grandfathers. Whereas having a father around did seem to aid children in getting married earlier, a living papa did not increase the number of grandchildren.
Feb 10, 08: In the 1960s, British zoologist and author Desmond Morris first proposed that kissing might have evolved from the practice in which primate mothers chewed food for their young and then fed them mouth-to-mouth, lips puckered. Chimpanzees feed in this manner, so our hominid ancestors probably did, too. Pressing outturned lips against lips may have then later developed as a way to comfort hungry children when food was scarce and, in time, to express love and affection in general. The human species might eventually have taken these proto-parental kisses down other roads until we came up with the more passionate varieties we have today.
. . Silent chemical messengers called pheromones could have sped the evolution of the intimate kiss. Many animals and plants use pheromones to communicate with other members of the same species. Insects, in particular, are known to emit pheromones to signal alarm, for example, the presence of a food trail, or sexual attraction.
Feb 8, 08: Analysis of a 40,000-year-old tooth found in southern Greece suggests Neandertals were more mobile than once thought, paleontologists said. Analysis of the tooth —-part of the first and only Neandertal remains found in Greece-— showed the ancient human had spent at least part of its life away from the area where it died. Some experts believe Neandertals roamed over very limited areas, but others say they must have been more mobile, particularly when hunting.
. . The team analyzed tooth enamel for ratios of a strontium isotope, a naturally occurring metal found in food and water. Levels of the metal vary in different areas.
. . The tooth's levels of strontium showed that the Neandertal grew up at least 20 km from the discovery site. "I would have been surprised if Neandertals didn't move at least 20 km in their lifetime, or even in a year ... We're talking about humans, not trees", Finlayson said.
Feb 8, 08: Two Komodo dragons have hatched at the Sedgwick County Zoo, apparently without the fertilization of a male. The dragons, both males, are believed to be the first in North America known to have hatched by parthenogenesis.
Feb 6, 08: A "barcode" gene that can be used to distinguish between the majority of plant species has been identified, say scientists. This gene can be used to catalogue plant life, as it has a slightly different code between species but is nearly identical within a species. DNA barcoding is already a well-established technique in animals.
. . "We found that a small gene, gene matK located in the chloroplast of the plant, has enough variation to identify between species.
Feb 6, 08: Head lice taken from 1,000-year-old mummies in Peru support the idea that the little creatures accompanied humans on their first migration out of Africa, 100,000 years ago, researchers reported. Genetic tests showed the lice are nearly identical to strains found around the world that have been dated to when humans first began to colonize the rest of the world.
. . There are three known strains, or clades, of head lice -- A, B and C. Clade A is found everywhere, clade B is common in both North America and Europe, and clade C is rare. There had been a theory that clade B evolved separately in the Americas and that European explorers carried A to the Americas and brought B back to Europe with them. Reed, who showed in 2004 that clade A dated back to early humans, said he got to test the idea by accident.
. . The lice were collected off the heads of two mummies found in the southern Peruvian coastal desert, dated to around 1000 AD. The two heads, removed from the bodies by looters years before, had elaborately braided hair. Researchers collected more than 400 head lice from one and 500 from the other. He speculated that the elaborate braids would not allow for regular combing, thus making a haven for the little parasites.
. . Reed was able to get intact DNA from the lice and sequencing showed they were all clade A. That means the strain was distributed across the Americas hundreds of years before the first Europeans arrived. Reed believes he can use gene sequencing of lice to track and date human migrations all over the world.
. . Type A lice include both head and body lice. The bloodsucking creatures can only live on humans --they die very quickly away from their hosts and cannot survive on any other animals.
. . They can also transmit diseases such as typhus. Reed believes some mummified lice will carry the rickettsia bacteria that transmit typhus, and gene sequencing of these bacteria can also help trace routes of human migration. It is also possible to test the theory that typhus was a New World disease carried back to Europe by explorers, Reed said.
Feb 4, 08: New research shows that people with blue eyes have a single, common ancestor. Scientists have tracked down a genetic mutation which took place 6,000-10,000 years ago and is the cause of the eye color of all blue-eyed humans alive on the planet today.
Feb 4, 08: DNA of the common black rat has shed light on the ancient spread of rats, people and diseases around the globe. Studying the mitochondrial DNA of 165 black rat specimens from 32 countries around the world, a scientists have identified six distinct lineages in the black rat's family tree, each originating from a different part of Asia.
Feb 1, 08: A new species of mammal has been discovered in the mountains of Tanzania, scientists report. The bizarre-looking creature, dubbed Rhynochocyon udzungwensis, is a type of giant elephant shrew, or sengi. The cat-sized animal looks like a cross between a miniature antelope and a small anteater.
. . Despite its name, the creature, along with the 15 other known species of elephant shrew, is not actually related to shrews. In fact, the creature is more closely related to a group of African mammals, which includes elephants, sea cows, aardvarks and hyraxes, having shared a common ancestor with them about 100 million years ago.
Jan 31, 08: Eurasian reed warblers captured during migration and then dumped 1,000 km off course were able to find their way back to their original route, according to a study suggesting some birds can truly navigate.
. . This means that the birds could identify at least two coordinates roughly corresponding to geographic latitude and longitude and suggests they are not limited to north-south direction as some had thought. "This finding is surprising and presents a new intellectual challenge to bird migration researchers, namely which cues enable birds to determine their east-west position?"
Jan 31, 08: Brazilian paleontologists said they had found the fossil of a new species of prehistoric predator that represented a "missing link" to modern-day crocodiles. The well-preserved fossil of Montealtosuchus arrudacamposi, a medium-sized lizard-like predator measuring about 1.7 meters from head to tail, dates back about 80 million years.
Jan 30, 08: Chameleons first used color change to make them more noticeable rather than, as is popularly believed, to blend in, a study suggests.
. . The reptiles change color for a variety of purposes --communication, camouflage and temperature control. However, the reason why they first evolved this ability to flash bright colours was previously unclear. It was to allow them to signal to other chameleons, to fend off rivals or attract a mate, and not so they could match a greater variety of backgrounds."
. . By setting individual chameleons up in a duel with a series of opponents, the color range between the submissive and dominant colors could be measured. "If a male is challenged by another male, they both begin by showing their brightest colors --until one figures out the other is going to win and changes to a submissive, dark, 'don't beat me up color'."
Jan 30, 08: A species of hummingbird makes a chirping noise with its tail feathers, not its throat, a study using high-speed video has suggested. The exact source of the noise from male Anna's hummingbirds has been the subject of debate among researchers.
. . By using specialized footage, a team of US scientists were able to show that male hummingbirds' tail feathers vibrated during high-speed dives. "Many kinds of birds are reported to create aerodynamic sounds with their wings or tail, and this model may explain a wide diversity of non-vocal sounds produced by birds."
. . The birds dive towards the ground at speeds that exceed 80km/h during their displays for nearby females.
Jan 30, 08: Nearly a half a billion years ago, tiny horseshoe crabs crept along the shorelines much like today's larger versions do, new fossil evidence suggests. Two nearly complete fossil specimens discovered in Canada reveal a new genus of horseshoe crab, pushing their origins back at least 100 million years earlier than previously thought. The ancient horseshoe crab is estimated to have been just 4 cm from head to tail-tip. That's much smaller than its modern-day relatives that can span nearly 50 cm.
. . Horseshoe crabs are not true crabs and are instead more closely related to spiders and scorpions. And like their eight-legged relatives, horseshoe crabs sport a flexible exoskeleton made of chitin rather than the hard-shell armoring worn by crabs. Chitin degrades over time. For that reason, ancient specimens of horseshoe crabs have been sparse. "It's survived for at least 445 million years in more or less the same form", Rudkin said.
Jan 30, 08: As vulnerable as naked mole rats seem, researchers now find the hairless, bucktoothed rodents are invulnerable to the pain of acid and the sting of chili peppers. A better understanding of pain resistance in these sausage-like creatures could lead to new drugs for people with chronic pain.
. . Naked mole rats live in cramped, oxygen-starved burrows some 2 meters underground in central East Africa. Unusually, they are cold-blooded —-which, as far as anyone knows, is unique among mammals.
. . Scientists knew the mole rats were quite sensitive to touch —-perhaps to help replace their almost useless eyes. After probing their skin, Park and his colleagues unexpectedly discovered the rodents lacked the chemical Substance P, which causes the feeling of burning pain in mammals.
. . The mole rat is the only animal that shows completely no response to acid." Scientists theorize naked mole rats evolved this insensitivity to acid due to underground living. The rodents exhale high levels of CO2, and in such tight, poorly ventilated spaces it builds up in tissues, making them more acidic. In response, the mole rats became desensitized to acid.
. . "To give you an idea of what they experience, we normally all breathe in CO2 levels of less than 0.1%. We hypothesize that naked mole rats live in up to 10% CO2."
Jan 22, 08: Dinosaur doomsday was wetter than scientists have thought, according to new images of the crater where the space rock that likely killed the jumbo reptiles landed. Sixty-five million years ago, the asteroid struck the north coast of the Yucatan Peninsula.
. . Geophysicists now have created the most detailed 3-D seismic images yet of the mostly submerged Chicxulub impact crater. The data reveal that the asteroid landed in deeper water than previously assumed and therefore released about 6.5 times more water vapor into the atmosphere.
. . The images also show the crater contained sulfur-rich sediments that would have reacted with the water vapor to create sulfate aerosols. These compounds in the atmosphere would have made the impact deadlier by cooling the climate and producing acid rain. The asteroid impact alone was probably not responsible for the mass extinction, Gulick said. More likely, a combination of environmental changes over different time scales took their toll.
. . Many large land animals, including the dinosaurs, might have baked to death within hours or days of the impact as ejected material fell from the sky, heating the atmosphere and setting off firestorms. More gradual changes in climate and acidity might have had a larger impact in the oceans.
. . If there were more acid rain than scientists had previously calculated, it could help explain why many smaller marine creatures were affected, because the rain could have turned the oceans more acidic. There is some evidence that marine organisms more resistant to a range of pH survived, while more sensitive creatures did not.
Jan 22, 08: An almost complete human skull fossil that could date back 100,000 years has been unearthed in China, state media said, hailing it as the greatest discovery since Peking Man. The fossil consists of 16 pieces of the skull with protruding eyebrows and a small forehead. "More astonishing than the completeness of the skull is that it still has a fossilized membrane on the inner side, so scientists can track the nerves of the Paleolithic ancestors."
. . Peking Man was discovered in the 1920s near Beijing and dates back roughly to between 250,000 and 400,000 years.
Jan 16, 08: A self-destructing palm tree that flowers once every 100 years and then dies has been discovered on the Indian Ocean island of Madagascar, botanists said. Botanists discovered a new species of giant self-destructing palm in Madagascar which is so large that it can be seen in satellite photos. Although villagers knew of its existence, none had seen it flower. When this finally happened last year, botanists found that the tree spent so much energy flowering that it died.
. . The palm is 20m high with leaves 5m long, the tallest tree of its type in the country; but for most of its life --around 100 years-- it appears fairly unremarkable apart from its size.
. . "At first there's only a very long shoot like asparagus from the top of the tree and then, a few weeks later, this unique shoot starts to spread. At the end of this process you can have something like a Christmas tree." The branches then become covered with hundreds of tiny flowers, which are pollinated and turn into fruit.
. . Scientists have identified 92 individual trees, all confined to the same remote area. It bears a resemblance to a species of palm found in regions of Asia, 6,000km away. It is possible that the palm has quietly gone through a remarkable evolution since Madagascar split with India some 80 million years ago.
. . They now hope that the plant will be conserved and that selling seeds can generate revenue for people living nearby, as well as allowing gardeners across the world to own their very own self-destructing Malagasy palm tree.
. . Madagascar is home to more than 10,000 plant species, 90% of which occur nowhere else in the world. These include 170 known species of palm.
Jan 16, 08: A parasitic worm can make its ant victims swell into what looks like a delicious, juicy berry to birds, which apparently eat the ants and help the worm spread and reproduce, U.S. researchers reported.
. . The nematode, a type of roundworm, changes not only the appearance of the ant but also its behavior, with the ants holding out their bloated, glowing abdomens to entice the birds. The black ants, found in the forests of Panama, are foul-tasting and not usually eaten by birds. The parasite and the way it works are new to science.
. . "I definitely saw birds come in and seemingly stop and take a second look at those ants before flying off, probably because the ants were moving."
. . The researchers said that if the birds ate the ants, they could spread the worm's eggs in their droppings. These eggs would then be gathered by other ants who then feed and unwittingly infect their young.
. . "It's just crazy that something as dumb as a nematode can manipulate its host's exterior morphology and behavior in ways sufficient to convince a clever bird to facilitate transmission of the nematode. It's phenomenal that these nematodes actually turn the ants bright red, and that they look so much like the fruits in the forest canopy."
Jan 16, 08: "Mighty Mouse"! Imagine a rodent so big it weighs a ton and is the size of a bull. A herbivore, the beast may have been a contemporary —-and possibly prey-— of saber-toothed cats and giant carnivorous birds that roamed the area millions of years ago, but Blanco said it was not clear whether such predators had the power necessary to bring down the huge beast.
. . "We report the discovery of an exceptionally well preserved fossil skull of a new species of rodent, by far the largest ever recorded. But it had small teeth and weak jawbones. "These features suggest that J. monesi had weak masticatory muscles for grinding food and probably did not have the abrasive diet typical of other (similar) rodents", they wrote. It probably ate soft food such as fruit or tender plants.
. . It spent nearly two decades in a box at the museum before it was rediscovered by a curator. The skull was huge —-more than 20 inches long. They warned that the estimate they made of the animal's bulk was imprecise —-he said it weighed between 1,700 and 3,000 pounds. It and other rodents grew bigger and bigger by filling the ecological niche taken elsewhere by rhinos and hippos. But when North and South America were linked about 3 million years ago, the rodents were swamped by North American animals and eventually died out.
. . The largest living rodent is the carpincho or capybara found in parts of South America. They can grow to about 60 kg.
Jan 15, 08: A 100-million-year-old haul of dinosaur eggs and fossils from China and smuggled illegally into Australia is headed back to Beijing.
Jan 15, 08: Scientists in the US say they have created a genetically-engineered carrot that provides extra calcium. They hope that adding the vegetable to a normal diet could help ward off conditions such as brittle bone disease and osteoporosis. Someone eating the new carrot absorbs 41% more calcium than if they ate the old. On its own, the carrot would not meet the daily requirement of 1,000mg of calcium, but if other vegetables were similarly engineered, intake could be increased dramatically. The calcium-charged vegetable still needs to go through many safety trials.
. . Dairy foods are the primary dietary source of calcium but some are allergic to these while others are told to avoid consuming too much due to their high fat content.
. . The orange color we know is the result of Dutch cultivation in the 17th Century, when patriotic growers turned a vegetable which was then purple into the color of the national flag.
. . Genetic engineering is being used to develop potatoes with more starch and less water so that they absorb less oil when fried, producing healthier chips or crisps. Work is also being carried out on broccoli so that it contains more sulforaphane, a chemical which may help people ward off cancer.
Jan 15, 08: Scientists have found inside the fossilized bones of three different types of dinosaurs the remains of a special type of calcium-rich bone tissue that forms just before egg-laying to enable pregnant female to produce eggshells.
. . "It's actually really common to start reproducing before you're done growing. Most animals do that. Reptiles do that. Medium- and large-sized mammals do that. Whether our parents like it or not, humans do that", Werning said. But birds do not reproduce before adulthood. "They finish growing completely. And they all do it within about a year. And then they wait months or years before starting to have sex."
. . The life span of these types of dinosaurs was about 25 to 30 years, she said, but they did not achieve full adult stature until about age 20, and there was a lot of adult mortality in this dino-eat-dino world. That would leave just a handful of years to reproduce and ensure species survival. "If you start reproducing earlier, you have more time and more chances to reproduce."
. . The discovery adds weight to the idea that dinosaurs were more like birds than reptiles. It also suggests that the reproductive strategy of modern birds is an ancient one, dating back some 200 million years, to when dinosaurs first evolved. "They're growing as fast as big birds and big mammals. To do this you can't have the metabolism of a crocodile; you need to have the metabolism more of a bird or a mammal."
Jan 14, 08: Adolescent pregnancy isn't a modern invention, it occurred in dinosaurs millions of years ago. Medullary bone, a type of tissue present in modern birds when they are developing eggs, has been found in three dinosaur fossils, researchers report. The dinosaurs were aged 8, 10 and 18, indicating they reached sexual maturity earlier than previously thought.
. . In modern birds, medullary tissue lines bones for only a few weeks when they are producing eggs and is then reabsorbed. Finding it in dinosaurs, which are believed to be the ancestors of birds, sheds light on their reproduction also.
. . Most dinosaurs lived to only about age 30, though some reached 60, the researchers said. Werner said in a statement that pinpointing the age of reproductive maturity "opens up so many complementary avenues of dinosaur research. You can talk about dinosaur physiology, lifespan, reproductive strategies. And you could use this technique to look at all kinds of extinct animals."
. . The medullary bones examined by Werner and Lee came from the meat-eater Allosaurus and the plant-eater Tenontosaurus. It's also been found in Tyrannosaurus rex.
Jan 10, 08: The rule of unintended consequences —-drop your guard because one threat goes away and an unexpected menace jumps up and smacks you. And new research shows it even applies to African acacia trees. For thousands of years, these thorny shrubs have provided food and shelter to aggressive biting ants, which protect the trees by attacking animals that try and eat the acacia leaves. Called mutualism, it's a good deal for both the trees and the ants.
. . Scientists studying the decline in large animals in Africa wondered what would happen if they no longer were eating the leaves. So they fenced off some of the acacias, so elephants, giraffes and other animals couldn't get to them.
. . Surprisingly, after a few years, the fenced-in trees began looking sickly and grew slower than their unfenced relatives. It turns out that without animals eating their leaves the trees no longer bothered to take care of their ants —-they reduced nectar production and made fewer swollen thorns that the ants could live in. The result: The protective ants either began damaging the plant or were replaced by other insects that ate holes in the bark.
. . "Although this mutualism between ants and plants has likely evolved over very long time-scales, it falls apart very, very rapidly." Some ants reduced their defensive behavior and began tending colonies of scale insects that bore into the plants and extract sugars. Others were replaced by other ant species that eat elsewhere and encourage the presence of wood-borer beetles, which eat holes in the trees that the ants can then use as home.
. . Palmer means to expose the trees again to browsing, "to see how quickly trees will re-induce their investments in symbiotic ants, and in turn, whether such reinvestment will be enough and in time, or too little, too late."
Jan 9, 08: A fossil unearthed in China has given scientists a rare glimpse of what dinosaurs were like in the flesh. The plant-eating Psittacosaurus had a thick layer of shark-like skin hidden under scales or feathers.
. . Palaeontologists believe this tough outer coating supported the dinosaur's organs and protected it from predators. Tooth marks suggest the dinosaur was torn open by a scavenger, giving a unique insight into their biology, 100 million years after this one's death.
. . The bipedal herbivore, which grew to about the size of a gazelle, had tough, scaly skin with more than 25 layers of collagen --similar to that of today's sharks, reptiles and dolphins.
. . "As noted from the studies on modern-day animals, this fibre structure plays a critical part in the stresses and strains the skin may be subjected to and is ideally suited to providing support and protection." He said the skin of the dinosaur would have been "incredibly tough" and probably served to protect the animal from attack by predators. "We imagine this Psittacosaurus as a tubby little animal walking around on its back legs."
. . Tooth marks and fractures in the skin suggest it was attacked by another dinosaur, and then covered by sediment rapidly after its demise, allowing soft tissue to be preserved in remarkable detail.
Jan 9, 08: Scientists have discovered genetic information that helps explain how monarch butterflies find their way from Canada to winter nesting grounds in the mountains of Mexico.
. . The study found that the butterflies' biological clocks help them use the sun as a compass. They said monarch butterflies have unique circadian clocks, which regulate daily activities like sleep and hunger.
. . The researchers genetically mapped the molecular underpinings of the butterflies' circadian clocks and found cryptochrome proteins common in both insects and mammals. Reppert believes these proteins enable the monarchs to navigate using the sun's position in the sky. "A butterfly's brain is no bigger than the head of a pin, and yet it has this incredible capability. So we really want to understand that."
Jan 3, 08: The National Academy of Sciences today issued a spirited defense of evolution as the bedrock principle of modern biology, arguing that it, not creationism, must be taught in public school science classes.
. . The academy, which operates under a mandate from Congress to advise the government on science and technology matters, issued the report at a time when the theory of evolution, first offered in the 19th century, faces renewed attack by some religious conservatives.
. . Creationism, based on the explanation offered in the Bible, and the related idea of "intelligent design" are not science and, as such, should not be taught in public school science classrooms, according to the report. "We need a citizenry that's trained in real science."
. . The report stated that the idea of evolution can be fully compatible with religious faith. "Science and religion are different ways of understanding the world. Needlessly placing them in opposition reduces the potential of each to contribute to a better future", said the report.
. . But teaching creationist ideas in science classes confuses students about what constitutes science and what does not, according to the report's authors. "Biological evolution is one of the most important ideas of modern science. Evolution is supported by abundant evidence from many different fields of scientific investigation. It underlies the modern biological sciences, including the biomedical sciences, and has applications in many other scientific and engineering disciplines", the report stated.
. . The authors highlighted developments in evolutionary biology, citing its importance in understanding emerging infectious diseases. They noted the discovery, published in 2006, of the remains of a Tiktaalik, a creature described as an evolutionary link between fish and the first vertebrate animals that walked out of water onto land 375 million years ago.
. . Evolution is a continuing topic of debate in some states. Florida officials are considering revisions in state science standards that would add the word "evolution" to the standards. The state Board of Education plans to vote on the guidelines next month.
. . "Despite the lack of scientific evidence for creationist positions, some advocates continue to demand that various forms of creationism be taught together with or in place of evolution in science classes", the report says.
Jan 3, 08: Call it the cuckoo of butterflies. Like the well-known birds, the Alcon blue butterfly has found a way to get others to raise its offspring. Researchers in Denmark report that the large blue butterfly has managed to produce larvae with a chemical coating similar to that of the local Myrmica rubra ants.
. . The butterflies deposit their larvae on marsh gentian plants where exploring ants find them, identify the chemical coating, and take the butterfly larvae back to the ant colony and feed them until they grow up and leave, the researchers report. Elsewhere in Europe the Alcon butterfly uses a different ant species to raise its young.
Jan 2, 08: The basis for laughter may have originated in an ancient primate ancestral to both humans and modern apes, a study suggests.
. . Scientists found that orangutans had a sense of empathy and mimicry which forms an essential part of laughter. Facial expressions, such as the open, gaping mouth resembling laughter, were picked up and copied by orangutans. The speed with which they were mimicked suggests these expressions were involuntary.
. . In other words, the "laughter" was contagious. When one of the orangutans displayed an open, gaping mouth, its playmate would often display the same expression less than half a second later. Dr Davila Ross commented: "In humans, mimicking behavior can be voluntary and involuntary. Until our discovery there had been no evidence that animals had similar responses. She added that the findings shed a new light on empathy and its importance for animals which live in groups such as orangutans.
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