The Nat paleontological collection contains the remains of the first saber-like predator that anticipated the appearance of cats. We are talking about a representative of machaeroidins – Diegoaelurus vanvalkenburghae. Dr. Sean Zach of the University of Arizona College of Medicine at PeerJ writes about the find.

The remains specimen of Diegoaelurus vanvalkenburghae is a lower jaw and well-preserved teeth. According to paleontologists, it was one of the first species that ate exclusively meat.

“Today, an all-meat diet in animals – hypercarnivory – is not uncommon. This is how tigers and polar bears eat. A domestic cat can also be a hyperpredator. But 42 million years ago, mammals were just beginning to figure out how to survive on meat alone,” says Dr. Ashley Post, a researcher at The Nat. “But the great achievement of evolution was the appearance of teeth for cutting flesh, which is what we see in the described specimen.”

This early meat-eating predator is part of a mysterious group of animals called machaeroidins. Now completely extinct, they were not closely related to modern predators. “We know so little about Machaeroidines, so each new discovery greatly expands our understanding of them,” said co-author Dr. Sean Zach of the University of Arizona College of Medicine. “This relatively complete, well-preserved fossil of Diegoaelurus is particularly useful because the discovered teeth allow us to infer the diet and how machaeroidins are related to each other.”

D. vanvalkenburghae was about the size of a lynx, but with a drooping, bony chin that protected its long, saber-shaped upper teeth. This would be a powerful and relatively new type of hunter.

“Nothing like this has ever existed in mammals,” Post notes. “Some mammalian ancestors had long fangs, but Diegoaelurus and its few relatives represent the first ‘feline approach’ to an all-meat diet, with saber teeth in front and scissor teeth in the back.”

This animal and its relatives represent a kind of evolutionary experiment, the first example of hypercarnivory, a lifestyle that real cats follow today.

“Diegoaleurus, although old, is the most recent of these machaeroidine predators. This puts it in close proximity to the time when the next feline animals arrived in North America, nimravids or saber-toothed fake cats,” he said. “Whether these groups ever met or even competed for space and prey, we don’t know yet.”