Andrewsarchus walking along a beach


The life and habits of Andrewsarchus have been inferred from study of a colossal 83cm skull fossil and a few other pieces of bone. If its body was proportioned to its skull like its nearest relatives, the mesonychids, Andrewsarchus would have measured 5 metres from nose to tail, making it a contender for the title of largest ever carnivorous land mammal. Its teeth and jaws were very strong, indicating a diet that incorporated a lot of hard items such as bone and turtle shell. Andrewsarchus was related to the cloven-hoofed animals, such as pigs and deer, so probably had hooves rather than paws.

Scientific name: Andrewsarchus

Rank: Genus

Common names:

Andrews' ruler

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Discover what these behaviours are and how different plants and animals use them.

Additional data source: Animal Diversity Web

When they lived

Discover the other animals and plants that lived during the following geological time periods.

Eocene epoch Eocene epoch
The Eocene began as a time of global warming, with temperatures across the planet soaring. Forests thrived and trees grew even in polar regions.


  1. Life
  2. Animals
  3. Vertebrates
  4. Mammals
  5. Mesonychia
  6. Triisodontidae
  7. Andrewsarchus