(ORDO NEWS) — Tyrannosaurus rex was a fierce hunter with the most powerful bite of any animal that ever walked on land.
This beast roamed the Late Cretaceous wilderness over 66 million years ago and ate Triceratops and Edmontosaurus for lunch.
The only thing that didn’t pose a threat in the form of a tyrant lizard was its tiny hands.
Tyrannosaurus Rex wasn’t the only dinosaur with small arms compared to the rest of its body; many of its theropod cousins a group of bipedal, mostly carnivorous dinosaurs shared this trait. But why did so many theropods develop such short, non-functional forelimbs?
A 2021 study published in the journal Acta Paleontologica Polonica found that bone-crushing theropods like T. rex ate their prey in packs.
Perhaps they have developed small limbs simply so that they are not accidentally bitten off by relatives who greedily pounce on prey.
However, this is still just a hypothesis. John Hutchinson, a biologist at the Royal Veterinary College London University who studies the biomechanics of movement of large land animals, both modern and extinct, looks at the evolution of dinosaur forelimbs in a different way: in his opinion, “arms did not actually get shorter, just legs got longer.
“As animals get bigger, the forelimbs get smaller and the head gets bigger. Tyrannosaurs developed a powerful bite, and therefore focused on their head, giving up their forelimbs, ”he writes.
As planned, the more often the head was used, the less the need for strong arms arose, so that in the end they simply reduced.
Tyrannosaurus rex’s arms were too short to help it hunt and kill. According to Hutchinson, these huge dinosaurs used the “prick-and-pull” method, in which the Tyrannosaurus rex bit off the victims “large pieces, tearing them off with a jerk of powerful neck muscles.”
He added that modern Komodo monitor lizards (Varanus komodoensis) also hunt this way. Large hind legs would help to stabilize the position of the body during such a bite, but the front legs would be useless.
It is tempting to suggest that every trait that an animal possesses plays some sort of evolutionary role in helping the creature survive.
But sometimes traits just appear (or disappear) that don’t necessarily bring clear evolutionary benefits. In this case, this character, the length of the forelimbs, did not change, while other characters underwent metamorphoses.
Other tyrannosaurus body parts grew to colossal proportions to help them survive in their ecological niche. It may not have been necessary for the arms to grow with the rest of the T-Rex’s body, making them look comically small in comparison.
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