Quirks & Quarks

As big as a hippo, but speedy like a cheetah: Meet the intimidating Anteosaurus

An ancient hippo-sized reptile was previously thought to be slow and sluggish because of its size. But researchers made a surprising discovery that the Anteosaurus would have been agile like a mountain lion.

Giant reptile roamed what is now the African continent before the dawn of the dinosaurs

A animation of Anteosaurus attacking a herbivorous Moschognathus. The hippo-sized predator was fast and agile, according to a new study. (Alex Bernardini)

Researchers studying an ancient predator made a surprising discovery that suggests the bulky reptile would have been fast and speedy, comparable to a modern-day mountain lion.

Anteosaurus roamed the African continent around 260 million years ago, in the time before dinosaurs. Due to its size, researchers had assumed that despite their predatory nature, they would have been slow and cumbersome animals.

But while using modern imaging technology to look at the details of their skulls, paleontologist Julien Benoit noticed that the inner ear and frontal lobe area of the Anteosaurus looked quite similar to that of fast-moving predators like the modern cheetah, or dinosaurs like the velociraptor.

"The inner ear is not only the organ of hearing, it's also the organ of balance. So locomotion has a direct effect on the anatomy of the inner ear," he told Quirks & Quarks host Bob McDonald. 

The skull of Anteosaurus compared to a modern human. (Wits University)

This means that the Anteosaurus would have "a good sense of balance, and also a very good coordination between the motions of the eyes, the motions of the head and the motions of the body, which is something that you would find in species that are good at tracking their prey," said Benoit.

Benoit is based at the University of the Witwatersrand in Johannesburg, South Africa. He and his team took what they'd learned and used a common measure in biology to calculate the animal's "agility score," and found that the Anteosaurus' score was comparable to a mountain lion.

"Now, was it really as agile as a mountain lion? Maybe, maybe not. But it was definitely more agile than the other things that were living at the same time," he said.

You can listen to the full interview at the link above.

Produced and written by Amanda Buckiewicz


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