For years, paleontologists have been trying to understand why dinosaurs such as the T-Rex had tiny arms that were a fraction of its body size. Now, a breakthrough is in sight - with a new study by researchers suggesting it had more to do with the dinosaur's strong head.
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TRANSCRIPT
"It's an outlier among outliers. Its entire family is very weird. The tyrannosaurs have very strong heads as a whole, and they are relatively big, but they were still compared to T-Rex, quite fast, quite agile animals, T-Rex took that idea of a massive predator with a strong head and smaller arms and kind of went into overdrive because, I think I'm right saying was probably the only giant animal for thousands of miles."
That's the lead author of a new study by University College London and Cambridge Charlie Roger Scherer.
He refers to dinosaurs such as Tyrannosaurus rex or T-Rex as an extreme among extremes.
For years, paleontologists have been trying to understand why T-rex's had tiny arms that were a fraction of its eight tonne body size.
Now, a breakthrough is in sight - with a new study by the group of scientists suggesting it had more to do with the dinosaur's strong heads.
The study - published in the journal Proceedings of the Royal Society B - looked at data for 82 species of two legged, carnivorous dinosaurs, including the T-Rex.
The research found smaller arms in meat-eating dinosaurs were linked to the development of large, robust skulls and jaws.
Scherer says the predators skulls were developed to be used as a primary weapon, and coincided with the increasing size of prey.
"And if it needs all of that energy to maintain its equipment for hunting, like a very strong, very heavy skull, it doesn't really want to, evolution doesn't want to use it for anything else. So it kind of says, okay, we'll take away from the arms because the arms aren't really much use to us anymore, but I'm not using them as a hunting. thing we'll put all that energy into growing a bigger stronger skull."
But a question still looms - why did the T-rex have arms at all?
Scherer says the species could have gone on to develop no forearms, but that didn't happen.
He says some hypothesis suggests that the T-Rex hung on to its forearms for support to get up from a resting position.
But Scherer - who believes the tiny forearms must have served some function - says that's unlikely.
"I don't know how likely that is, because you're trying to lift up an eight ton animal with arms no bigger than a human. It's like, that's interesting, but it's it's something that is a scientific hypothesis that could be tested."
According to National Geographic, T-Rex dinosaurs had a massive body - a mouth of 68 inches long, supersharp teeth and the strongest bite of any land animal ever.
Before its extinction, T-Rex existed over what’s now North America and Asia, some 68 million years ago.
