Long before humans walked the planet, a massive creature ruled the forests and open plains of ancient Eurasia.

Virginia opossums are the only marsupial species in North America.

The Entelodont, the largest prehistoric pig to inhabit North America in the Eocene Period, could grow up to the size of a ...

A fossil shows a mammal biting into a dinosaur. The Repenomamus robustus appears to be attacking the Psittacosaurus, though it's much smaller.

That the average pre-asteroid mammal was puppy-scale did not sit well with a male Victorian view of evolution as a struggle for “dominance” won by large animals — your megalosauruses and ...

The mammal died while biting two of the dinosaur’s left anterior dorsal ribs; its mandible plunges downward into the indurated sediment to firmly clasp the bones (Fig. 1; Supplementary Fig. S9).

Other Mammals, Not Dinosaurs, Kept Our Ancestors Down The asteroid impact that ended the Cretaceous gave our mammalian ancestors, the therians, an edge over their mammalian competitors ...

Eventually, this intensive review of the fossils resulted in the identification of the three new prehistoric mammal species of prehistoric mammals, each with a unique set of dental features. Atteberry ...

But melanin pigments have also been found inside some animals, prompting the question of what their functions are inside the body. The answer, it turns out, has changed over time.

Echidnas are quill-covered mammals that are native to Australia and New Guinea. They lay eggs like their platypus cousins, ...