Can you run faster than a T. rex? According to new research, you can surpass one by walking.
In the movie “Jurassic Park” (Warner Bros., 1993), a bunch of scared people famously try to escape a fence T. rex, but science quickly casts shadows on the movie beast and shows that the king of tyrannosaurs would not be fast enough to drive off with a jeep. Now researchers have slowed down the big dinosaur even more.
New simulations based on tail movement have shown this T. rex was not even a quick hiker. In fact, its preferred running speed was just under 5 km / h (about 5 km / h), about half the speed of earlier estimates. To put this in perspective, it is according to the British Heart Foundation.
Related: Image Gallery: The Life of T. rex
Tyrannosaurus rex, the largest of all carnivorous dinosaurs, lived in the present Western United States, about 66 million to 68 million years ago by the end of the Chalk period, and they probably counted in the billions.
An adult T. rex would have stood about 12 meters long, 3.6 meters long and weighed on average about 5 to 7 000 kilograms, according to the American Museum of Nature in New York City. The heaviest known T. rex, a sturdy monster found in Saskatchewan, Canada, nicknamed “Scotty”, weighed 8,870 kg. Live Science reported earlier.
But how fast can such a large animal move? Previously, researchers answered that question by looking at T. rex‘s mass and hip height, which sometimes include the length of the track of the retained track. Those estimates place a T. rexspeeds of 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 it T. rexAccording to 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.
“Dinosaur tails have been vital to the way they move around in various ways,” van Bijlert emailed WordsSideKick. “Not only does it serve as a counterbalance, but the tail also provides much of the strength needed to move the body forward. It does this through two large tail muscles – the caudofemoral muscles – that pull the legs backwards during each step.”
Passive and active
In the biped (biped) T. rex, the tail would hang passively in the air, but also be actively engaged and of course swing up and down during walking. “This combination – passive suspension while active in motion – is unique to dinosaurs; there are no animals living this function today,” Van Bijlert explained. ‘As a result, we were very intrigued by his role in the way T. rex would have walked. ‘
As a T. rex tail swings, it stores and releases energy through stretchable ligaments. When the rhythm of a swinging tail resonates – ‘the greatest movement response with the least effort’ – that rhythm is known as the tail’s ‘natural frequency’, Van Bijlert said. The natural frequency in a T. rex tail will then indicate the animal’s gait frequency during a hurried walk, the researchers write in the new study, which was published in the journal on April 21. Royal Society Open Science.
Related: In pictures: a new look at T. rex and his family members
To stand as the researchers’ model T. rex was a copy for adults known as ‘Trix’, in the collection of the Naturalis Biodiversity Center in Leiden, the Netherlands. The authors of the study scanned and modeled Trix’s tailbones, referring to marks on the well-preserved vertebrae that showed where ligaments were attached. From this digital bone and ligament reconstruction, they created a biomechanical model of the tail.
“The tail model gives you a probable step frequency / rhythm for T. rex“But you also need to know how much distance it takes with each step,” Van Bijlert said. To find it, scientists took the step length of a tyrannosaurus slightly smaller than Trix, and scaled it up to the size of Trix They determined that Trix’s walking length would be 1.9 m (6.2 feet), and then calculated the walking speed by multiplying the walking frequency by the walking length.
“Our baseline model has a preferred running speed of 2.86 mph [4.6 km/h]”which was significantly slower than previously estimated in terms of running speed,” Van Bijlert said in the email. ” Depending on some assumptions about the ligaments and how the vertebrae rotate, you become slightly slower or faster (1.79 to 3.67 km / h) [2.88 to 5.9 km/h]’, but overall, they are all slower than previously estimated,’ he said.
Cover new ground
However, there is still some uncertainty in this series, as it focuses on the up-and-down movements, “and muscles – as well as side-to-side movements – are not considered,” John Hutchinson, a professor of evolutionary biomechanics at the Royal Veterinary College in Hertfordshire, UK, told Live Science by email.
“No one in the right mind thought dinosaurs had completely stiff tails (up / down or side / side), but that was a neglected topic for movement,” said Hutchinson, who was not involved in the new research. “So, this study covers a new ground in a smart way with an original model.”
The new estimate also reflects a ‘large emphasis on elastic storage’, the study’s authors write, and the storage capacity of tyrannosaurus tails may be lower than the model suggests, Hutchinson added. Nevertheless, this flexible tail model would be ‘useful to integrate and compare with other approaches in the future,’ he said.
As for T. rexIn the following steps, the authors want to incorporate the flexible tail into the running models T. rex, said Bijlert. Maximum running speed for a T. rex is believed to be between 16 and 40 km / h (10 to 25 km / h), according to Hutchinson. Biomechanics researchers have long suggested this T. rexThe maximum running speed would be limited by the strength of his legs, because the animal was so heavy. However, a flexible tail can change this by acting as a shock absorber while running, allowing him to run faster without breaking his legs, Van Bijlert said.
“We also want to apply our method to more species because it can cause interesting evolutionary adjustments in the role of the tail in motion,” he added.
Originally published on Live Science.