“Must go faster!” Could you outrun a T-rex?
Congratulations! Your time machine works! You’ve travelled back more than 66 million years and arrived in the Cretaceous period.
But, oh no! You’ve barely had chance to admire your surroundings before a thumping shakes the ground beneath you. Suddenly you notice a shadow lurking in the forest. A large shadow. And then a Tyrannosaurus Rex emerges from the trees.
You need to make a decision, and fast. Should you run or should you hide (assuming you don’t have a Jeep like Dr Ian Malcolm in one of Jurassic Park’s most iconic scenes)? Well, with his long, powerful hind legs, your instinct will probably tell you to run from a T-rex – and until today, scientists may have told you the same.
We non-palaeontologists may be too busy chuckling at T-rex’s tiny arms to give much thought to its huge, powerful hind legs, but it’s been speculated by many experts that these long limbs made the carnivore a competent runner. Over 100 years of research and speculation have gone into working out the speeds it could reach.
However, a new report from researchers that include scientists from the School of Earth and Environmental Sciences here at The University of Manchester has suggested this may not be the case. Using a combination of two separate biomechanical techniques – skeletal stress analysis and multibody dynamic analysis – the authors reveal that, in fact, it’s unlikely that T-rex would have run at all.
In reality, it’s those long powerful legs that most likely would have prevented T-rex from running. The scientists created two films depicting the locomotion of the giant creature – one demonstrating a walking gait and the other running. The researchers considered whether the dinosaur could have reached a running speed of around 18 mph and created a film that showed it doing as such – but there was a catch…
…quite a big catch, as it turns out. The running gait would have put so much pressure on T-rex’s skeleton, it would have broken it. And that’s quite a hindrance if you’re trying to catch your lunch.
One of the stumbling blocks scientists have encountered when considering how fast a T-rex moves is how to incorporate both physical evidence, such as the limb proportions taken from fossilised remains, with conjecture – most notably the soft tissue parameters that are rarely preserved and so need to be estimated.
To overcome this, the team combined the virtual robotic approach of multibody dynamics with machine learning algorithms and stress analysis. This allowed them to determine the maximum speed a T-rex could reach without jeopardising its skeletal safety. You can watch the video they produced by clicking here.
Speaking of the findings, the researchers say: “It is somewhat paradoxical that the relatively long and gracile limbs of T-rex – long argued to indicate competent running ability – would actually have mechanically limited it to walking gaits, and indeed maximised its walking speed.”
How did T-rex hunt?
If T-rex couldn’t run, how did it hunt? After all, the researchers acknowledge that there appears to be “direct evidence” of predatory behaviour in the species – meaning it’s unlikely that T-rex survived solely as a scavenger.
Rather, the researchers think that as the dinosaur matured and grew, it went after larger prey – animals that would have similarly limited locomotion.
Run or hide?
So back to our original dilemma. If a T-rex is after you, should you run or hide? Your instinct may be to hide – after all, doesn’t Jurassic Park’s Dr Alan Grant assure us that “he can’t see you if you don’t move”?
Well we have news for you: T-rex may not have been able to run, but it could certainly see – and very well too, according to an earlier report from the University of Oregon. So hiding may not be the best option against this hide and seek champion.
But now we know that T-rex couldn’t run, surely your best option is to sprint off without looking back? Well, you could try this, but – thanks to the length of its limbs – the walking pace of a T-rex is estimated to be 11 mph. That’s only marginally slower than the running speed of the average human, which is 15mph – and even then, that can only be achieved for short bursts.
If you want our advice (and you’re not Usain Bolt, who’s been clocked running at a speed of nearly 28 mph), the best way to escape a T-rex: don’t travel back in time in the first place. And there you have it!
Words – Hayley Cox