It is one of the most memorable chase scenes in modern cinematic history. The image of a rampaging Tyrannosaurus rex (T. rex) chasing Jeff Goldblum as he sits injured in the back of a 4x4 vehicle in Stephen Spielberg’s original film adaptation of Jurassic Park.
T.Rex Chase Scene, Jurassic Park. Scene Credit Universal Studios
Like me, plenty of people have wondered just how fast a Tyrannosaurus rex could run. But that may well have been the wrong question. People should have been asking if this fearsome dinosaur was able to run at all. In fact, new research from Prof William Sellers of the University of Manchester says the sheer size and weight of T. rex means it couldn’t move at high speed, as its leg-bones would have buckled under its own weight load. Yet this creature could obviously outrace its prey. And scientists now say that if it were alive today, T. rex probably could catch most people, too.
Past studies have used several methods to try to estimate the speed of a T. rex, Sellers notes. Some accounted for the creature’s size, weight and muscle bulk. (Researchers have to guess at the size of a dinosaur’s muscles, since they don’t survive in fossils.) Others have looked at fossil footprints, taking detailed measurements of their size and spacing. Some researchers, including those on Sellers’ team, have even used computers to model, or simulate, the dino’s gait.
"Being limited to walking speeds contradicts arguments of high-speed pursuit predation for the largest bipedal dinosaurs like T. rex and demonstrates the power of Multiphysics approaches for locomotor reconstructions of extinct animals," he said, adding that the new modelling technique was likely to enhance current thinking of other big beasts.
"Tyrannosaurus rex is one of the largest bipedal animals to have ever evolved and walked the earth. So it represents a useful model for understanding the biomechanics of other similar animals," said Sellers. "Therefore, these finding may well translate to other long-limbed giants, but this idea should be tested alongside experimental validation work on other bipedal species."
Prof Sellers says the results demonstrate any running gaits for T. rex would probably lead to ‘unacceptably high skeletal loads’. Meaning, in layman’s terms, any running would simply break the dinosaur’s legs. This contradicts the results of previous biomedical studies. Such studies gave mixed results. Their estimates for a T. rex’s top speed ranged from 5 to 20 meters per second. That’s about 18 to 72 kilometers per hour.
He explains: ‘the running ability of T. rex and other similarly giant dinosaurs has been intensely debated amongst paleontologist for decades. However, different studies using differing methodologies have produced a very wide range of top speed estimates and we say there is a need to develop techniques that can improve these predictions.
‘Here we present a new approach that combines two separate biomechanical techniques to demonstrate that true running gaits would probably lead to unacceptably high skeletal loads in T. rex.’
While T. rex might have struggled to catch a meal, whatever it did catch stood little chance in the jaws of the king of the dinosaurs; a study published earlier this year found that a Tyrannosaurus rex had a bite force of 7,800 pounds-force (34,522 newtons) -- equal to the weight of three small cars.
Although the research focuses on the T. rex, the findings also means running at high speeds were probably highly unlikely for other large two-legged dinosaurs such as, Giganotosaurus, Mapusaurus, and Acrocanthosaurus.
Source: Peer Journal