The sleek, lizard-like Compsognathus, which lived about 150 million years ago and weighed just 3kg, could run 100m in a little over six seconds, a speed that would leave modern Olympic athletes more than a third of the track behind.An average specimen could reach a top speed of almost 64km/h according to a new computer simulation. This would make it faster than the ostrich, the quickest on land of all modern bipeds.
The simulation found that a 65kg ostrich should have a top speed of 55.4km/h — much faster than humans, but a slowcoach next to Compsognathus.
It would also have far outpaced all the other dinosaurs tested so far with the biomechanics model developed at the University of Manchester. The velociraptor, whose speed and ferocity was highlighted in the film Jurassic Park, reached 39km/h while the T-rex could muster speeds of up to 29km/h.
Bill Sellers, a biomechanics expert who led the study with Philip Manning, a paleontologist, said it was plausible that Compsognathus was the fastest animal on two legs ever to have lived. “It is certainly by far the quickest in terms of our results,” he said. “It would have done the 100m in about six seconds.”
In the study, which is published in the journal Proceedings of the Royal Society, Dr Sellers and Dr Manning used a supercomputer to reconstruct the speeds of five dinosaurs: Compsognathus, Velociraptor, Tyrannosaurus rex, Dilophosaurus and Allosaurus.
All were two-legged predators belonging to the theropod group of dinosaurs, but they ranged in size from 3kg for an average-sized Compsognathus to six tonnes for T. rex.
The computer used details of each dinosaur’s anatomy to work out its most efficient gait, taking up to a week to learn the optimum biomechanics for each animal. It started with a clumsy stumble, and gradually learnt the right posture and stride to run as fast as possible.
The model was calibrated using data from a 71kg man with the muscle and bone structure of a professional athlete, and a predicted top speed of 28.4km/h.
Although this is slower than the 37km/h or so top speeds reached by Olympic sprinters, it is representative of a very fit man such as a footballer.
Data from a 65kg ostrich and a 27kg emu were then fed into the system, producing top speeds of 55.5km/h and 48km/h respectively. The dinosaurs had an even wider spread of top speeds. T. rex was the slowest, at 28.8km/h, but even this was slightly faster than a human.
“The figures we have produced are the best estimate to date as to how fast these prehistoric animals could run,” Dr Manning said.