Anthracothere

Anthracotheres were an extinct family of hoofed mammals that lived from the Eocene to the Miocene epochs. The name anthracothere means "burning beast," referring to the discovery of their fossils in coal deposits. These animals were semi-aquatic, with a lifestyle that likely resembled that of modern hippopotamuses. Their skeletons suggest they were robust and had webbed feet, indicating adaptation for a life in and around water. Anthracotheres possessed a distinctive dental structure, with selenodont molars that were adapted for grinding vegetation.

The earliest known anthracotheres appeared in Eurasia during the Eocene. Over time, they diversified and spread to Africa and the Americas. Their ecological niche appears to have been that of herbivores, grazing on aquatic plants and soft terrestrial vegetation. They varied in size, with some being as small as a pig and others comparable to a hippopotamus. The family is thought to be an early offshoot of the artiodactyls, the order that includes modern even-toed ungulates like deer, cattle, and hippos.

The decline of anthracotheres began in the Miocene, likely due to competition with other herbivores and changes in their aquatic habitats. By the end of the Miocene, the group had largely disappeared. The only surviving lineage, the hippopotamuses, evolved from a closely related group of anthracotheres and are their closest living relatives. Anthracothere fossils provide valuable insights into the evolutionary history of mammals and the paleoecology of ancient aquatic environments.