The researchers first tested the model by applying it to living animals, including humans, ostriches, and the Australian emu.
"We got the information from modern animals, which we then put into the model in the same way we would for an extinct animal, and the speeds were pretty accurate," Manning said. "They were in tune with what we'd expect for the modern species."
An ostrich, the fastest two-footed runner alive today, topped out at 34 miles an hour (55 kilometers an hour) in the model. A fit human came in a smidge slower than T. rex.
The team then plugged in the details of five meat-eating dinosaurs.
According to the simulations, the chicken-size Compsognathus ranked as the fastest dinosaur, reaching a top speed of nearly 40 miles an hour (64 kilometers an hour).
Manning said the top speeds are likely conservative, since the strongest possible muscle and bone configurations have yet to be modeled.
The team is currently working with the National Geographic Society to create a 3-D model of how dinosaurs moved. It involves more muscles and thus even more complicated calculations, Sellers noted.
(National Geographic News is part of the National Geographic Society.)
"The idea there is to produce something that is actually more accurate kinematically, [that] actually produces more realistic movements," Sellers said.
John Hutchinson is an expert in the biomechanics of living and extinct animals at the University of London's Royal Veterinary College. He complimented the recent simulation as an advance in understanding dino locomotion.
"My previous work just looked at one part of the step," he said.
But, he said, the method requires many assumptions about the skeletal and muscular structure of these extinct animals, assumptions that need to be carefully considered before firm conclusions are drawn.
"I've never even done or trusted approaches like this, because there're a lot of assumptions that go into these models and it's very easy to get misled or get overconfident about the results," he noted.
Nevertheless, Hutchinson said, most of the speeds obtained from the computer model are in line with the range of speeds suggested from his own modeling studies, although he disagrees with the use of a definitive top speed.
"There's no way you can be that precise for an extinct animal," he said.
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