Some were the size of a dog. Others were as large as polar bears. A newly-discovered fossil of the ferocious hyaenodont is helping scientists understand a little bit more about the mysterious ...

It was likely a "hypercarnivore," scientists say — a carnivore with a diet of more than 70% meat. Related: Mysterious 'hypercarnivore' with blade-like teeth roamed California 42 million years ago ...

With sharp catlike teeth and a doglike body, ancient carnivores called hyaenodonts were once at the top of the food chain, but the entire lineage was wiped out about 25 million years ago ...

Bearing sharp teeth and powerful jaw muscles, suggesting a strong bite, the newly-identified "Bastetodon" was a leopard-sized "fearsome" mammal. It would have been at the top of all carnivores and ...

Hyaenodonts evolved long before modern-day carnivores such as cats, dogs, and hyenas. These predators with hyena-like teeth hunted in African ecosystems after the extinction of the dinosaurs.

With sharp catlike teeth and a doglike body, ancient carnivores called hyaenodonts were once at the top of the food chain, but the entire lineage was wiped out about 25 million years ago ...