/ 6 April 2017

Tyrannosaurus rex, a sexy softie

Sexy Rexy: T rex used his snout.
Sexy Rexy: T rex used his snout.

Tyrannosaurus rex spent its life wandering across the planet, tearing into anything that it wanted to eat. Claws and massive teeth made it the king of nature. Any attempt to fight back was halted by plates of thick armour around its face. It took an asteroid, and catastrophic climate change, to end its dominance.

You’d be forgiven for thinking that T rex was all bad. And Hollywood doesn’t help their image.

But new science shows the 18-tonne carnivore had a soft side; the tip of its snout. Short on arms to wrap around each other, the toothy terrors would instead rub their noses against each other to get in the mood to mate.

That is according to research published in the journal Nature’s, Scientific Reports. “A new tyrannosaur with evidence for anagenesis and crocodile-like facial sensory system” based its findings on the discovery of a new dinosaur in the tyrannosaur family. Daspletosaurus horneri was a slightly smaller ancestor of T  rex but had the same makeup.

Unlike T  rex, the discovery of D  horneri came with a trove of almost intact skulls and skeletons. Much of what is known about T  rex has come from incomplete skeletons, and predictions of how it would have walked and lived. The discovery enabled researchers to fill in the gaps.

When it comes to getting it on, the researchers concluded: “In courtship, tyrannosauridae might have rubbed their sensitive faces together as a vital part of precopulatory play.”

They could do this because the thick skin and armour around its snout had small openings, packed with trigeminal nerves. This allowed the snout to have the same sort of sensitivity and tactile response as a hand, allowing T  rex to interact with its environment. That meant it could gently pick up eggs, and its young when they cracked out of those.

These nerves are present across species, allowing them to interact in different ways with their surroundings. Crocodiles use them to sense vibrations in the water and birds to sense approaching prey or predators.

Crocodiles also use them for foreplay. These last remnants of the Jurassic age have a similar patch of nerves around their jaws, which they rub together before mating.

Like crocodiles, T rex had a soft side, as long as you weren’t its prey.