Beating Beckham
In the film The Lost World: Jurassic Park, a six tonne tyrannosaurus rex runs faster than a state-of-the-art Sports Utility Vehicle, but the latest computer simulations estimate that at a top speed of 18 miles per hour, the prehistoric giant probably ran slightly faster than a professional footballer!

Biomechanics expert Dr Bill Sellers at the University of Manchester, UK and palaeontologist Dr Phillip Manning have built computer models featuring the leg bones, muscles, and skeletal structures of five different types of dinosaur, including the tyrannosaurus rex. They believe they have produced the best estimates to date of how fast these animals moved.

Animating fossils
For Dr Sellers it was a short step from studying robotic gait simulation to using computer simulation to get fossils moving. ‘My particular interest is in dinosaurs and locomotion,’ he says, ‘these are the biggest land animals that ever lived. It’s the extreme, the biggest or the smallest, that often tells us about the fundamental principles behind something so they are a very important group to study.’

His training as a zoologist and computer scientist gives him the unique skills necessary for this work. He describes it as a ‘robotics technique.’ Using existing knowledge of dinosaurs’ muscle and skeleton structure, ‘we can get the computer to generate the activation pattern for the muscles. It’s called a forward dynamic model. That means we apply forces and the model calculates the movement based on the forward locomotion. The challenge is finding a stable locomotion so the model doesn’t fall flat on its face.’

Credible simulations
To check the credibility of their results, they simulated living animals: the human, the ostrich and the emu, all relatively high-speed bipedal animals to compare to bipedal dinosaurs. Contrary to depictions of prehistoric life as slow and lumbering, Sellers says, ‘our work suggests that these animals were quick, and life was much more like the modern savannah with animals moving about at a relatively fast pace.’

‘The more legs you try to simulate, the harder it becomes’ says Sellers. ‘We've done some work on quadripedal animals and we'd love to look at the triceratops and the big sauropods. We'd also like to look at things other than locomotion, such as flight and swimming.’ Eventually Sellers intends to collaborate in creating virtual prehistoric worlds.