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Caltech Scientists Measure Dinosaur Body Temp
damn_registrars writes "Using rare isotope ratios, a geology team at CalTech has determined body temperatures of sauropod dinosaurs. Their work finds temperatures that are roughly in line with modern mammals for body temperature. However, as the authors point out, this does not on its own confirm dinosaurs to be entirely warm-blooded, as they may have kept these temperatures by sheer mass. The peer-reviewed paper is available online in PNAS. You can also get the article free through pubmed."
You'd think the reason this took so long was because they had to fabricate a thermometer large enough, but in fact the real hold up was convincing a grad student to stick that thermometer up the dinosaur's ass.
. . . that big a rectal thermometer?
"I believe in Karma. That means I can do bad things to people all day long and I assume they deserve it." : Dogbert
That is all.
The point about body mass, if it's not clear, is that metabolism produces huge amounts of heat. When we digest food, about 50% of the energy that's released in converting complex molecules to carbon dioxide and water is released as heat. A huge animal can keep warm just from that. Mammals and birds maintain their temperature in a very narrow range. However, it's more complicated than just that would indicate: hibernating mammals (and one species of bird that hibernates) allow their temperature to fluctuate with the outside temperature. Likewise, there are reptiles that do some things to reduce their temperature variation, by seeking sunlight or shade, which is a type of active regulation. One current theory about dinosaurs and the evolution of feathers is that they showed up primarily as a thermoregulation system, providing insulation (particularly in rain) but allowing the animals to fluff their feathers to increase temperature losses to again actively thermoregulate.
Nostalgia's not what it used to be.
Were dinosaurs slow and lumbering, or quick and agile? It depends largely on whether they were cold or warm blooded. When dinosaurs were first discovered in the mid-19th century, paleontologists thought they were plodding beasts that had to rely on their environments to keep warm, like modern-day reptiles.
The writer is a moron.
No those paleontologists didn't fucking think that. The only damn reason the T. Rex in the American Museum of Natural History was mounted upright like that was because it was too damn heavy to mount with the backbone horizontal using the technology of the day.
Why the hell is there this general belief that people today are SOOO much smarter than people in the past?
I don't see the connection between the mounting position of a T.Rex and the speed or agileness of dinosaurs in general? The erect T-Rex doesn't look any more lumbering than a prone T-Rex to my untrained eye.
And is it really true that it takes modern structural materials to mount a t-rex horizontally? It seems like even in the early 1900's, they could have used a steel beam and cables to hang it if they really wanted to show it in a more horizontal position.
This reference says that scientists didn't discover until the 1970's that the upright position was not accurate, but it was because of biomechanics, not speed or agility.
http://landbeforetime.wikia.com/wiki/Tyrannosaurus
Henry Fairfield Osborn, former president of the American Museum of Natural History (AMNH) in New York City, who believed the creature stood upright, further reinforced the notion after unveiling the first complete T. rex skeleton in 1915. It stood in this upright pose for nearly a century, until it was dismantled in 1992.[48] By 1970, scientists realized this pose was incorrect and could not have been maintained by a living animal, as it would have resulted in the dislocation or weakening of several joints, including the hips and the articulation between the head and the spinal column.[49]
Warm blooded? The next thing they are going to tell us is that dinosaurs had feathers.
Star Trek, there maybe hope.