New research paper theorizes Tyrannosaurus rex was built for slow walking
Now we are all committed to remembering the wild scene of 1993 jurassic park where a rampaging Tyrannosaurus rex chases a gasoline Jeep over Isla Nublar, the vehicle’s side mirror indicating that “objects in the mirror are closer than they appear”.
For decades, the consensus among paleontologists was that the T. rex was a fast runner and capable of open ground speeds of up to 30 miles per hour, which is close to sprint mode for gold medalist Olympian Usain. Bolt.
Past speculation about the T. rex’s maximum speed has always focused on the creature’s mass, hip height, and stride length indicated by fossilized footprints. Conservative estimates concluded that the predator’s walking speed was likely between 4.5 and 6.7 miles per hour. But step on the brakes, because those older numbers could be a bit high.
Now, a new research paper published this week in the online journal Royal Society Open Science ignores the obsession with the robust legs of T. rex by studying the critical role of its elastic tail and the unique sway, vertical movement it displayed in numerical simulations. Based on the study of the new biomechanics, the beast’s ambulatory limits have been significantly reduced to 3 miles per hour.
“Dinosaur tails were essential to the way they moved, in a number of ways,” lead author Pasha van Bijlert, a master’s student in paleo-biomechanics at the Free University of Amsterdam, told Live Science. “Not only does this serve as a counterweight, but the tail also produces much of the force needed to move the body forward. It does this through two large muscles in the tail – the caudemoral muscles – which pull the legs backwards. with each step.
“This combination – passive suspension while being active in locomotion – is unique to dinosaurs; there are no animals living today with this characteristic. For this reason, we were very intrigued by its role in how T. rex would have worked. “
Watching how a T. rex tail swings, energy is stored and released via a network of stretch ligaments. Upon attaining a rhythmic sway, the thick appendix achieves a resonance called “natural frequency,” which can be used to gauge the animal’s natural walking pace.
To create a complete animated simulation, van Bijlert and his colleagues scanned an adult T. rex skeleton named “Trix” from the Naturalis Biodiversity Center in the Netherlands. From there, the researchers found markings on the well-preserved vertebrae that indicated ligament attachment locations to provide a workable biomechanical model of the tail. A predetermined walking length of 6.2 feet was agreed upon for the study.
“The tail pattern gives you a likely step rate / rate for the T. rex, but you also need to know the distance it travels with each step,” van Bijlert added. “Our base model had a preferred walking speed of 2.86 mph. Based on some assumptions about ligaments and spinal rotation, you get slightly slower or faster speeds of 1.79 to 3.67 mph, but overall, they are all slower than previous estimates. ”
There are still lingering questions and variables to consider in this simulation that might not adequately address the impact of meat eater muscles and side-to-side tail movement.
“No one in their right mind thought dinosaurs had perfectly rigid tails (top / bottom or side / side), but this is a neglected topic for locomotion,” notes John Hutchinson, professor of evolutionary biomechanics at the Royal Veterinary College. in Hertfordshire, in the email from Live Science. “So this study covers new ground in a smart way with an original model.”