Little Arms, Big Wounds: What the T-Rex Really Did With Those Small Arms

When you think of a dinosaur, you most likely think about the T. rex. Among the most iconic of extinct species, the tyrannosaurus rex has been the poster child for dinosaurs for years. Despite their intimidating stature and deadly predatory abilities, something about the T. rex has been a bit of a joke for years: they have almost comically small arms. Compared to the proportions of the rest of the body, members of the species have a “lopsided” look about them. Don’t let the myths or jokes fool you. People don’t call the tyrannosaurus the “king of the dinosaurs” for no reason.


Their Arms Were a Show of Strength

 T.rex’s arms are a reminder of the species’ past. Ancestors of the tyrannical lizard had longer arms used for grasping. As evolution progressed, the arms gave way to the jaw as a primary means for grasping. This was especially effective since it was predominantly used for grasping and killing prey.

Many people assume that because T. rex had small arms, it was not strong. Contrary to that belief, the fact that the arms were so small is actually proof that the nine ton reptile was a wholly unstoppable force after all. T. rex’s strength was not in its arms. In order to be a predator at the top of the food chain, it need to have a ruthless, crushing bite. Such a bite required powerful jaw muscles which in turn required a large head. According to paleontologists, the species’ characteristically lethal bite would not be possible without those seemingly weak arms.

Their Arms Provided Attack Power

Tyrannosaurus’ arms weren’t useless at all. Researchers have suggested that they may have also used them for slashing prey. According to several experts, the bones in the arms were strong enough to sustain the impact of slashing. T. rex arms also ended in two claws each measuring around 10 centimeters in length. Experts also noted that the claws were beveled and sharp, similar to bear claws. Unlike the dull, flat talons of an eagle, the dinosaur could have used its arms to slash prey.

This hypothesis applies in particular to young a young T. rex. While not as effective on an adult, juvenile member of the species might have taken advantage of their arms. The arms grew markedly slower than the rest of the body, meaning that young dinosaurs could still attack prey even as they continued to hone their proficiency with their jaws.

Their Arms Helped Them in Other Ways

Other hypotheses attempt to explain what role the arms of the T. rex played. Surprisingly enough given their size, some scientists suggest that the arms were actually used in the mating process. Male tyrannosaurus would use its arms to hold a female in place during mating. This hypothesis, while possible, is also up for a great deal of debate. Considering how little researchers currently know about dinosaur sex, there is no way to tell for sure whether or not the stories are true.

Still others believe that the small arms served a function during battle. If knocked over during a skirmish with a rival predator or particularly obstinate prey, T. rex could use its arms to help leverage itself off the ground. Being able to get off the ground quickly would certainly come in handy when going up against a stegosaurus that was none too pleased about having to fight not to become food.

What do you think about the T. rex? Do you think any of these theories regarding the uses of their arms are true? Do you think that the species will continue to be the butt of jokes and cruel memes everywhere based solely on the size of its appendages? Let us hear what you have to say in our comments section.

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