Why the T-Rex Had Tiny Arms Revealed

For as long as kids have known that dinosaurs existed, the Tyrannosaurus rex has reigned supreme as one of the most memorable animals of all time, with its massive size and seemingly ferocious demeanor both fascinating and frightening anyone familiar with the "Tyrant Lizard King." Despite the creature's massive size, their arms were diminutive compared to the rest of its body, making it the butt of many jokes. For those curious, PBS Eons recently reminded viewers that the main reason that the T. rex didn't have long arms was simply that they didn't need them.

"The characteristics we think of as defining T. rex, namely a huge head and tiny forelimbs, were actually part of a 90-million-year trend in that direction," the video notes. "And that big head wasn't just for looks, its enormous jaws gave T. rex a bite force up to 57,000 Newtons, which is enough to pulverize bone with a bite. Having long forelimbs wasn't really necessary, but beyond that, long arms were just not needed. For some dinosaurs, they were kind of in the way."

New discoveries and advances in technology have changed our perception of a variety of species over the years, with our perception of extinct animals regularly evolving.

Based on the massive size of the animals, researchers initially thought that the T. rex was a legendary hunter, yet, upon further analysis, many theories have emerged that the beast was actually a scavenger. The short arms would have rendered the animal relatively useless when it came to combat, while some scientists have claimed the animal's massive size would have made it's top running speed a measly 10 miles per hour. Additionally, its small eyes would have given it poor eyesight, rendering its stalking and hunting skills poor.

In 1993, the live-action adaptation of Jurassic Park made dinosaurs more popular than ever, though it was far from scientifically accurate. Even if the novel and film used the most reliable resources available, much has changed in the world of paleontology in the last 25 years.

Another iconic animal from the film, the Velociraptor, was inaccurately represented in the film. Novel author Michael Crichton likely drew inspiration from the Utahraptor or Deinonychus for his portrayal of the Velociraptor, as those creatures reached much larger heights than the Velociraptor, which reached heights of only three feet.

As mentioned by Dr. Alan Grant early on in Jurassic Park, dinosaurs have more in common with modern-day birds than reptiles, which includes some dinosaur species likely having feathers. Some theories argue that even the Velociraptor had feathers, which would completely alter their appearance in the dinosaur movie franchise.


Audiences can see Hollywood T. rexes and Velociraptors in Jurassic World: Fallen Kingdom, in theaters now.

Do you wish the Jurassic Park films were more scientifically accurate? Let us know in the comments below!