Mammals and dinosaurs coexisted on Earth until a catastrophic event 66 million years ago killed 75% of life on the planet.

Illustration showing Repenomamus robustus as it attacks Psittacosaurus lujiatunensis moments before a volcanic debris flow buries them both, ca. 125 million years ago. (Michael Skrepnick via ...

The lower jaws of lizards, birds, fish and even dinosaurs are comprised of multiple bones per side. Yet mammals diverged from all other vertebrates and settled on just one bone, repurposing the extra ...

Discover the complete list of egg-laying mammals, known as monotremes. Learn about the unique biology of the platypus and the four species of echidnas. Monotremes are a class of mammals that are known ...

A new fossil described this week captures two intertwined animals caught in a life-or-death struggle right before both were entombed in a volcanic event. Published in Scientific Reports this Tuesday, ...

New research published in the Journal of Anatomy has used dental evidence to challenge the origin time of mammals. The study, an international collaboration led by the Federal University of Rio Grande ...