EDMONTON - A University of Alberta scientist has found that some dinosaurs could really shake a tail feather.
Scott Persons says that far from being the lumbering, cold-blooded beasts of Hollywood myth, at least one species of the long-extinct animals had strong, flexible tails tipped with large fans of feathers "built for flaunting."
"Don't think of a trip back to the Mesozoic like a saunter through a reptile house," said Persons. "Think of it as a trip to Las Vegas, because there would be tail-feather fans on show girls for you."
Persons' newly published paper is about Oviraptors, a species of flightless dinosaur distantly related to T. Rex with a vegetarian diet, crested heads and birdlike beaks. They ranged in size from about that of a modern turkey to eight metres long and lived between 145 and 66 million years ago.
Studying fossils from recent finds in Mongolia, Persons realized all his Oviraptors would have had long, nimble tails with attachments for powerful muscles to swish them back and forth. He also found the tails ended in pieces of solid bone called pygostyles, features found in only one other kind of animal — modern birds.
"They serve as the anchor point for broad tail-feather fans."
Although no fossilized feathers were found in the deposits Persons studied, he points out that they have been found with other, earlier Oviraptors — complete with colour banding. Combining the discovery of pygostyles with previous evidence of Oviraptor feathers led him to his conclusion.
"You stick a feather fan on the end of a highly dextrous and muscular tail and you've got what I think is a tail built for flaunting, that could shake a tail feather side to side, raise it up, strike a pose," Persons said. "Probably to an extent that's greater than a modern-day peacock or a turkey."
Persons can't yet say if all Oviraptors boasted tail feathers. Pygostyles are delicate and easily destroyed, leaving open the question of how wide a fan a creature eight metres long could have spread.
Persons' findings flesh out a new understanding of dinosaurs very different than that held a couple of decades ago. Scientists now believe that dinosaurs used feathers for the same reasons modern birds do including flight, display and insulation.
What's more, feathered dinosaurs were common, but only some eventually evolved into birds. Most, like Oviraptor, simply died out.
"It shows you that you had sophisticated feathers in other dinosaur lineages as well, not just the ones related to birds," Persons said.
Discoveries such as this allow scientists to draw conclusions both about what dinosaurs looked like and how they may have behaved, Persons said.
"This is an instance where how they look is probably very much related to how they behaved," he said.
"The old view of dinosaurs ... as big, slow-moving, dull, cold-blooded reptiles, sort of hanging out, basking in the sun, lurching up and going to get something to eat before coming back down ... is wrong.
"The Oviraptors, you can think of these elegant, long-legged, fast, apparently warm-blooded dinosaurs that are doing more with their time than sunbathing and eating — dinosaurs that are investing time and energy and material into displays."