Why tyrannosaurs had such small forepaws

Tyrannosaurs are one of the most popular dinosaurs and certainly the most famous predators of prehistoric times. Their impressive appearance, powerful jaws, impressive strong legs contrast brightly with tiny front paws, which at first glance seem completely useless. There are many jokes and caricatures on this subject, but jokes are jokes, why do the main dinosaur thunderstorm need such “stumps” at all? Paleontologists have been looking for the answer to this question for many years.

Arms are too short

More than 100 years after the discovery of the T.Rex species, experts still do not know why a huge animal, which reached about 12 meters in height, had forelimbs not much larger than an adult. If the hands were weak, without special muscles, the simplest explanation would be the idea that they are not needed at all. However, several studies claim that judging by the muscle scars left on the bones of tyrannosaurs, an adult dinosaur could lift more than 100 kilograms with each bicep.

However, this is not as impressive as it seems, against the background of the mass of the dinosaur itself, which could reach 8 tons. It’s as if a 90-pound person boasted that he could lift a 1 kg dumbbell for biceps. That is, in arm wrestling, a tyrannosaurus would defeat a man, but against the background of his remaining abilities, his forepaws are hardly proud.

Based on this, several experts came to the conclusion that the front legs of a tyrannosaurus were either useless or rarely used. But not all paleontologists think so: some believe that small limbs have become excellent hunting tools for predators.

Very fine motor skills

Several years ago, scientists carefully studied the bones of the forelimbs of tyrannosaurs and found traces of injuries and fractures on them. This suggests that the forelimbs were periodically exposed to strong impact. The most likely explanation for this is that T. Rex used his paws to grab a large, powerful prey. Such a prey could easily break the bone of a carnivorous dinosaur, or at least tear apart several muscles.

According to another version, tyrannosaurs used their forepaws to push themselves off the ground and stand on their feet after a fall. It is also possible that these short paws were useful in courtship.

Alas, there is currently insufficient evidence to conclusively refute or confirm any of these theories. However, there is one thing we can confidently say about the tiny front legs of the tyrannosaurus: they were not an anomaly.

Several species of large predatory dinosaurs lived on Earth, which had forepaws too small for their bodies. Indeed, close relatives of a tyrannosaurus fit for this description - for example, the Asian tarbosaurus and the North American daspletosaurus.

However, many famous predators with small forelimbs were not close relatives of tyrexes. That is, natural selection several times preserved this feature in different species. So, it was necessary for something. And for what - remains to be seen.

Watch the video: lesothosaurus (March 2024).

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