Giant Sea Reptiles Were Warm-Blooded?

nationalgeographic ^ | June 10, 2010 | Charles Q. Choi

[JoeProBono]

Giant reptiles that ruled dinosaur-era seas might have been warm-blooded, a new study says.

Researchers found that ancient ocean predators possibly regulated their body temperatures, which allowed for aggressive hunting, deep diving, and fast swimming over long distances.

(See "Giant 'Sea Monster' Fossil Discovered in Arctic.")

"These marine reptiles were able to maintain a high body temperature independently of the water temperature where they lived, from tropical to cold-temperate oceanic domains," said study co-author Christophe Lécuyer, a paleontologist at Université Claude Bernand Lyon 1 in France.

The prehistoric reptiles may have had body temperatures as high as 95 to 102 degrees Fahrenheit (35 to 39 degrees Celsius)—comparable to those of modern dolphins and whales, Lécuyer noted. (See whale pictures.)

Most modern reptiles and fish are cold-blooded, which means their internal temperatures vary along with those of the surrounding water.

Since the modern oceans' top predators—such as tuna and swordfish—are to some degree warm-blooded, this made the team wonder if ancient marine reptiles might have been, too, Lécuyer said.

Tuna and swordfish are homeothermic, or capable of keeping their body temperatures relatively constant, despite changing environmental temperatures. The predators are also partially endothermic, which means they can generate and retain enough heat to raise their body temperatures to high but stable levels.

Most animals thought of as warm-blooded, including mammals and birds, are also both homeothermic and endothermic

[JoeProBono]

[BubbaBasher]

If they were warm blooded then they wouldn't be reptiles now would they?

[UCANSEE2]

[JoeProBono]

[MrEdd]

[UCANSEE2]

[evets]

[JoeProBono]

[JoeProBono]

[UCANSEE2]

[Hotmetal]

Your 2nd illustration looks like a mosasaur. I have a vertebra from a mosasaur from a creek in Mississippi that i picked up.

[MrEdd]

[UCANSEE2]

[UCANSEE2]

[UCANSEE2]

[JoeProBono]

[evets]

[MrEdd]

http://www.youtube.com/watch?v=jU9Crc38eNc

[JoeProBono]

[mrreaganaut]

Godzilla ping!