Dinos had very high body temperatures.

[Odin2005]

http://www.sciencedaily.com/releases/2006/07/060712073816.htm



One of the larger animals, a behemoth called Sauroposeidon proteles, weighed close to 120,000 pounds as an adult. Now, a new study led by the University of Florida suggests it may have had a body temperature close to 48 degrees Celsius.

That is a 118-degree Fahrenheit normal temperature, about as hot as most living creatures can get before the proteins in their bodies actually begin to break down.

In fact, the size of the largest dinosaurs may ultimately have been limited by their body temperatures, according to a team of scientists from the UF Genetics Institute, the National Center for Ecological Analysis and Synthesis in Santa Barbara and the University of New Mexico writing this week in the online journal PLoS Biology.

"One of the first things to strike me about our results was that larger dinosaurs, for their size, were much more active than contemporary reptiles," said Andrew Allen, Ph.D., a researcher with the NCEAS. "If these animals functioned at temperatures of 35 or 40 degrees centigrade, it suggests that they operated at a rate more like today's mammals and birds. While the largest dinosaurs may not have been running around as fast as in 'Jurassic Park,' they certainly were very active given their extreme size."

[kestrel91316]

1. The environment was hotter then, too. I can't wait to see what the future

holds for us humans as earth heats up.

[bleever]

2. I thought this was a Lieberman thread.

Very interesting, nonetheless.

[bemildred]

3. Atmospheric oxygen concentrations were different then.

That ought to be factored in, I think, although I wouldn't know how.

[rman]

7. How it factors in: more 'energy' per breath of air;

oxygen is used to create energy in the body.

[bemildred]

9. Yes, but I don't know enough about dinosaurs.

There was a big drop in O2 concentration at the Permian-Triassic boundary (IIRC), but I don't know how the big fat Dinos fit into that timewise.

[Odin2005]

11. O2 levels varied throught the Mesozoic.

During the Triassic and early Jurassic the oxygen levels were lower then today, this is probably what lead dinosaurs to evolve a unique respatory system that is today only found in thier bird decendants. During the latter half of the Mesozoic the 02 levels were higher then today.

[bemildred]

12. That sounds right.

I've read elsewhere that it was the unique respiratory system that allowed birds to fly. One presumes that was after the O2 level went back up.

[Island Blue]

4. When I read you subject line

I instantly wondered why did a study on Joe Lieberman's body temperature.

[politicat]

5. "Ah, honey, not tonight... you're like an oven!"

Heard in dinosaur nests the world over.... and thus, extinction.

Ignore that comet. The hot hoochie mamma girl dinos were too much for the boy dinos.

[theHandpuppet]

6. I've wondered about how they kept their skins from being sun-scorched

Even today's snakes and lizards will seek some shade during the heat of the day in hotter climes, and mammals such as elephants and hippos have to keep their hides cool from the damaging rays of the sun. So what did dinos do, or did they really need it?

[frogmarch]

8. Maybe, like lizards,

the outer skin (scales, scutes, whatever) of dinosaurs was made of keratin. This is composed of dead skin cells like our hair and nails, and is not much affected by sunlight. Maybe that's why dinos didn't sunburn, if they didn't.

Maybe also like lizards, dinosaurs secreted melanin, which along with warming them up when needed by making them darker (maybe not all dinos were endotherms), also helped guard them from solar rays.

Heck, I dunno. Where's DinoBoy? Yoohoo!

[Odin2005]

10. Quite likely.

Also, Many large dinosaurs may have had adaptations to keep cool. Stegasaur plates were not covered with horn, but by skin riched in blood vessels used to shed heat. Diplodicid sauropods (like Brontosaurus) had the hole in the skull for thier nose on the top of thier head, this probably evolved in order to support a large, fleshy, external nose on top of the snout giving the animal a better abillity to shed heat.