According to new calculations by Dutch paleontologists, T. rex would have traveled just under 3 miles in an hour, a speed similar to that of humans and many other animals, at their preferred speed for walking. However, this rate is slower than other estimates of the marching speed of the tyrant sergeant king.
When they have no reason to run, most animals, including humans, have a natural walking speed that minimizes the amount of body energy expended.
Earlier estimates had not fully taken into account the role of T. rex’s tail – which is more than half its length – in breaking the figures, said Pasha van Bijlert, leader author of a new study on T. rex locomotion published Tuesday in the journal Royal Society Open Science.
“Animals usually prefer walking speeds at which, for a given distance, the energy cost is minimal. They do so by choosing specific pace of pace at which their body parts resonate. Since the entire tail of T. rex is suspended by ligaments, which behave like rubber bands, we reconstructed this tail to investigate at what rate of step the tail of T. rex would resonate, ”said van Bijlert, a graduate student in paleo-biomechanics at VU University Amsterdam, by email.
“The whole tail, for our reconstruction at almost 1,000 kilos, was really just a mass supported by a rubber band and with each step it would bounce slightly up and down. With the right pace you get a lot of movement for very little effort.”
The research team calculated a pace of passage from a computer model of a T. rex tail, based on Trix, an adult fossil of T. rex 12 meters long (39 feet). long). Naturalis Biodiversity Center, a natural history museum and research center in the Netherlands. The scientists multiplied the pace of the step by the length of the step found on the fossilized tracks for an estimated walking speed of 2.86 miles per hour.
Other methods, van Bijlert said, focus primarily on calculations based on the legs and hips. Certainly, they play a crucial role in the estimates, but calculations based only on these parts of the dino anatomy can cause inaccuracies. results. This is because T. rex and many other dinosaurs had unique tails that are not found with any other living animal today.
Similar to the walking speed of today’s animals
Understanding how an upper predator like T. rex moved can help paleontologists better understand the behavior of dinosaurs and ancient ecosystems by answering questions like: How much food did it need to move that huge body at that speed? How far would you have gone to find prey?
For example, a T. rex would use its preferred walking speed when walking toward a water source, van Bijlert said. “It can also give you an idea of what types of distances you can travel when looking for food.”
He did not estimate the maximum speed of T. rex in this research, but plans to do so using the same method in the future.
John Hutchinson, a professor of evolutionary biomechanics at Royal Veterinary College London, said the role of tails had been a neglected topic in dinosaur locomotion studies.
“How fast giant tyrannosaurs would normally have walked has not been a big question for many studies, but it is still an interesting question. The approach used here is complementary to more sophisticated muscle-based simulation studies and in a way , to data from fossil footprints, “he said in an email.
“This study covers new ground in a smart way with an original model. It’s interesting and it would be useful to integrate it and compare it with other approaches in the future.”
What surprised Van Bijlert most from the research was that the walking speed of T. rex that the team found was similar to that of a wide range of live animals today.
“Humans, ostriches, horses, elephants, giraffes, wildebeests, and gazelles have an extraordinarily narrow distribution at preferred speeds (approximately 2.2 – 3.1 mph). So this includes both animals. two-legged and four-legged, and also relatively small and large animals, “he said in an email.
“The interesting thing is that our new method predicts a slower walking speed for T. rex than other methods, but the speed we find is closer to many animals living today.”