New simulations calculated T. rex walking speed from the motion of its swaying tail.
Could you run faster than a T. rex? According to new research, you might be able to outpace one by walking.
In the movie “Jurassic Park” (Warner Bros, 1993), a carful of terrified people famously tries to escape a loping T. rex, but science quickly threw shade at the movie beast and demonstrated that the king of tyrannosaurs wouldn’t have been fast enough to run down a jeep. Now, researchers have slowed down the big dinosaur even more.
New simulations based on tail movement showed that T. rex wasn’t even a quick walker. In fact, its preferred walking speed clocked in at just under 3 mph (5 km/h), about half the speed of earlier estimates. To put that into perspective, that’s about the average walking speed for a human, according to the British Heart Foundation.
Tyrannosaurus rex, the biggest of all carnivorous dinosaurs, lived in what is now the western United States, from about 66 million to 68 million years ago toward the end of the Cretaceous period, and they likely numbered in the billions.
An adult T. rex would have measured about 40 feet (12 meters) long, stood 12 feet (3.6 m) tall and weighed about 11,000 to 15,500 pounds (5,000 to 7,000 kilograms) on average, according to the American Museum of Natural History in New York City. The heaviest known T. rex, a hefty specimen found in Saskatchewan, Canada, and nicknamed “Scotty,” weighed in at a whopping 19,555 pounds (8,870 kg), Live Science previously reported.
But how fast could such a big animal move? Previously, researchers answered that question by looking at T. rex‘s mass and hip height, sometimes incorporating stride length from preserved trackways. Those estimates placed a T. rex‘s walking speed roughly between 4.5 and 6.7 mph (7.2 and 10.8 km/h), about as fast as a mediocre human runner.
For the new investigation, rather than focusing on T. rex‘s legs, scientists instead explored the role played by the vertical movement of the tyrannosaur’s tail, said Pasha van Bijlert, a master’s candidate studying paleo-biomechanics at the Free University of Amsterdam, and the lead author of the new study on T. rex walking speed.