DINODATA

DINODATA

Stuff I found when I googled: GIGANTOTHERMY


MAIA (Maiasaur) means "good mother".


Mamenchisaurus --about 21 m long-- had the longest neck of any known dinosaur, about 14 m. It had 19 vertebrae in its neck, more than any other known dinosaur.
FLIGHT (& eyes) evolved many times: twice for bats; once (gliding only) with a lizard's elongated scales --on its back.

EYES: mollusks, even. Deep-sea fish have an area that can detect the presence of dim light, but not focus it in the slightest.


Oreodonts ("mountain tooth") the most common hoofed herbivorous mammals in North America during the Oligocene.
VERTEBRA The spine is made up of many vertebrae. The largest ever found were neck vertebrae that belonged to the long-necked dinosaur Seismosaurus; they are over 1.8 m long.
Thescelosaurus fossil whose fossilized, four-chambered heart was found, perhaps indicating this dinosaur was warm-blooded.
Small theropod Dinos had EQs equivalent to living mammals & birds.
Zygopophyses were interlocking bony structures on the back half of the tails of tetanuran dinosaurs. These zygopophyses project forwards and backwards from the neural arches, interlocking one vertebra into another, stiffening the tail.
GIGANTOTHERMY or mass-homeothermy

One argument against warm-blooded dinosaurs suggests that large dinosaurs such as the sauropods would not need to be warm-blooded, as their size alone would prevent temperature fluctuations. Heat production is related to body mass, while heat loss is related to body area. As an animal gets larger, its body area decreases relative to its mass, so heat loss decreases and it becomes more efficient at maintaining body temperature. This theory, termed 'gigantothermy', together with the possible aid of plates, spikes, frills or nasal cavities used as heat exchangers, proposes that large dinosaurs, living for the most part in a warm environment, could in fact have found that maintaining full warm-bloodedness was thermally stressful and disadvantageous.
. . There are a number of counter-arguments. Although gigantothermy provides for increased efficiency of temperature regulation, it is still far less efficient than true warm-bloodedness (6-8 degrees C variation instead of 1-2), and warm-blooded animals would still be expected to win easily in any evolutionary competition.
. . Gigantothermy also does not address the problem that all dinosaurs arose initially from relatively small ancestors, certainly too small for gigantothermy to have any impact. If these small ancestors had developed warm-bloodedness and thus competed effectively with the mammals for domination, why would evolution produce giant descendants that had lost the ability? The proposals regarding sails, plates and various other "heat exchangers" suffer from the observation that quite closely related species, both warm- and cold-blooded, may or may not have these additions. If they were important and obligatory for heat regulation, all species should have had them. It seems at present that these developments were probably evolved as display organs rather than heat exchangers.
. . Computer models have shown that this would regulate temperatures well in the large dinosaurs but not in juveniles or the much smaller forms and not if winters were very cold. However, there were no cold winters, as the climate when dinosaurs were alive was 15 degrees Celsius warmer than today. The models also showed that color was important.
. . Gigantothermy can provide a mechanism for temperature regulation (within one degree, if the outside temperature only varies between 22 & 32 degrees C daily) without the considerable requirements of a high metabolic rate. Because gigantootherms cannot cope if the temperature is too low, it has been suggested that dinosaurs became extinct because of climatic change, making their biological processes break down.


Many Dinos (like horses & human babies) could breathe while swallowing, but their ability was due to the presence of a secondary palate, a very non-reptilian feature; and some may have had a long prehensile tongue.
Thomas Huxley (way Back) realized that Dinos strongly resembled birds in many important aspects, and suggested that birds might be descended from dinos.
Temps on Earth during the Cretaceous were about 15 degrees C warmer than today.
If the KT-impactor was a comet, a surrounding, dusty coma, many 100's of thousands of miles across, would have heralded the comets arrival. Reflecting sunlight, the comet's coma would have illuminated the sky for weeks as it approached. When the edge of the coma reached Earth, a growing shower of dust and debris would have blazed in the high atmosphere, lasting hours or days before the comet's impact. ~Douglas Henderson, illustrator.

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