Anthracotheres

Anthracotheres were an extinct family of hoofed mammals that lived from the Eocene to the Miocene epochs. Their name, meaning "coal beasts," refers to the Eocene coal deposits in which their fossils were first discovered. Anthracotheres were a diverse group, with over two dozen genera identified, ranging in size from that of a small pig to a large hippopotamus.

These semi-aquatic artiodactyls are thought to have originated in Asia and later spread to Africa, Europe, and North America. Their anatomy suggests a lifestyle similar to modern hippos or tapirs, with adaptations for a life spent partly in water. They possessed relatively short legs, webbed feet, and a long, broad snout, likely used for foraging on aquatic vegetation. Their teeth were adapted for grinding plant material, indicating a herbivorous diet.

Anthracotheres had a distinctive dental formula and skull structure that helped paleontologists classify them. For a long time, their evolutionary relationships were unclear, but fossil evidence and molecular studies now place them within the order Artiodactyla, the even-toed ungulates. They are considered to be distantly related to hippos and whales, forming a clade known as Cetancodonta. The extinction of anthracotheres is not fully understood, but it likely occurred due to climate change and competition with other herbivores.