Rare Fossil Shows Theropod Dinosaurs Are Fast, Dangerous 'Turbocharged...( Oregon State University (OSU)...)

Oregon State University (OSU) scientists funded by the National Science Foundation (NSF) have completed a study of what they say is the world's most perfectly preserved fossil of a theropod, or meat-eating dinosaur. They believe it provides an unprecedented view of the biology of these ancient reptiles.

The bottom line? You wouldn't want to meet a theropod in a dark alley. The research, to be published in this week's issue of the journal Science, offers insights into dinosaur metabolism, the warm-blooded versus cold-blooded debate, the question of whether or not dinosaurs might have been the ancestors of birds, and the biology that helped them dominate the world -- and eventually may have led to their extinction.

"This exquisitely preserved fossil shows that theropod dinosaurs had the ventilatory machinery to support periods of high activity, but that they lacked bird-style lungs or other anatomical features suggestive of a sustained high metabolic rate," according to Zoe Eppley, program director in NSF's division of integrative biology and neuroscience, which funded the research. "This find adds further support to the view that these dinosaurs were not warm-blooded."

This fossil is helping confirm that "the dinosaurs were indeed, by definition, cold-blooded, and that in all likelihood, birds are not the descendants of any known group of dinosaurs," said Nicholas Geist, a paleobiologist at OSU. "The extraordinary condition of this fossil allows us to 'hang some meat on the bones' of these animals and bring them back to life a bit. It's almost like a dinosaur dissection."

What that analysis reveals, Geist said, is an animal that had the best of both worlds. Like other cold-blooded animals, theropod dinosaurs had low metabolic rates while at rest, an excellent strategy for conserving energy. But their enhanced lung ventilation capacity gave them the potential for the aggressive, extended activity ty
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Contact: Cheryl Dybas
cdybas@nsf.gov
703-306-1070
National Science Foundation
21-Jan-1999