A carnivorous wolf-like cow, Andrewsarchus is known from only a single skull recovered in the 1920s in Mongolia.

Andrewsarchus is known only from an enormous, meter-long skull and pieces of bone, but the skull's similarity to that of smaller mesonychids suggests that Andrewsarchus had the same wolf-like body on a larger scale. Extrapolating from the body proportions of similar mesonychids, Andrewsarchus was most likely about 4-6 metres (13-18 feet) long, standing nearly 2 metres (6 feet) at the shoulder, making it the largest terrestrial carnivorous mammal that has ever existed. It probably averaged about 1500 kilograms in weight with some exceptional animals over 2000 kilograms, making it over twice as heavy as most Kodiak brown bears, and rather heavier than a Percheron horse.





Andrewsarchus eating a brontothere, as big as a rhino, with a sarkastodon in the background, by John Sibbick

A life-sized model