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This is Scientific American 60-Second Science. I'm Christopher Entallata.

No one has ever seen a Tyrannosaurus walk. Still, movies like Jurassic Park have guessed how fast

it would have done that. Now scientists have used the skeleton of a T-Rex to model the biomechanics

of the animals' stride, and they've estimated it's strutted at a leisurely pace,

on par with humans, ostriches, elephants, and giraffes. And it's not just living to those

animals' horses, gazelles, news, turns out that actually most animals don't tend to walk super

fast. Pasha von Byler is a movement scientist at Vry University in Amsterdam. His team studied

the skeleton of a T-Rex housed in a Dutch museum. The specimen, nicknamed Trix, is exceptionally

well preserved, so they were able to see how ligaments would have attached to and linked the

animal's tail bones. Those ligaments, they would have acted like rubber bands, and the researchers

used mathematical modeling to study how they would have given the tail bounce as the T-Rex walked.

The animal could have taken advantage of that natural bouncy rhythm to save energy as it moved.

That is basically resonance. You get more movement for less effort if you choose the correct

rhythm at which you do things. So that helped them estimate the beat at which T-Rex would have

pounded its feet, but to determine speed, they still needed to know how far each step was.

And to do that, we found a fossilized trackway of a slightly smaller tyrannosaurid,

...