Archaeotherium

Archaeotherium
Temporal range: Eocene–Oligocene
Fossil of A. mortoni
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Artiodactyla
Family:
†Entelodontidae
Genus:
†Archaeotherium

Leidy, 1850
Species

Archaeotherium (whose name means "ancient beast", taken from the Ancient Greek words ἀρχαῖος arkhaîos, meaning 'ancient', and θηρίον thēríon, meaning 'wild animal' or 'beast.) was a type of mammal in the entelodont family; entelodonts are in turn in the artiodactyl family. Giraffes, camels, cattle, and deer are other artiodactyls that still live today. It only lived in North America between 35 and 28 million years ago during the Eocene and Oligocene eras.

A reconstruction of the animal by Elie Cherverlange

Description

Overall Description

These animals are sometimes called "hell pigs", but they are not pigs, instead being more like hippos and whales.

Its head was large, with bony lumps on its cheeks and strong jaws for eating both meat and plants.

Size

The biggest animals in the group Archaeotherium are a lot bigger than the smallest ones. The type species, A. mortoni, is quite small and slim. It is thought that it weighed around 150 kg (330 lb), and its skull was around 47 cm (19 in) long. The bigger kinds, those that used to be called Megachoreus, were much larger. A. zygomaticus's skull was around 78 cm (31 in). A. calkinsi is thought to have been stockier than other entelodonts. The biggest kind of Archaeotherium was A. trippensis.

References

  1. ↑ "archaeo-", Wiktionary, the free dictionary, 2025-08-21, retrieved 2026-01-25
  2. ↑ "ἀρχαῖος", Wiktionary, the free dictionary, 2025-12-26, retrieved 2026-01-25
  3. ↑ "-therium", Wiktionary, the free dictionary, 2024-10-05, retrieved 2026-01-25
  4. ↑ "θηρίον", Wiktionary, the free dictionary, 2025-12-27, retrieved 2026-01-25
  5. ↑ Joeckel, R. M. (1990). "A Functional Interpretation of the Masticatory System and Paleoecology of Entelodonts". Paleobiology. 16 (4): 459–482. Bibcode:1990Pbio...16..459J. doi:10.1017/S0094837300010198. ISSN 0094-8373. JSTOR 2400970.
  6. ↑ The evolution of artiodactyls. Internet Archive. Baltimore : Johns Hopkins University Press. 2007. ISBN 978-0-8018-8735-2.{{cite book}}: CS1 maint: others (link) CS1 maint: publisher location (link)
  7. ↑ digitallibrary.amnh.org https://digitallibrary.amnh.org/items/5267c192-b7c5-4599-99e7-11fac59e1718. Retrieved 2026-01-26. {{cite web}}: Missing or empty |title= (help)
  8. ↑ Albright, L. (1999-08-12). "Ungulates of the Toledo Bend Local Fauna (Late Arikareean, Early Miocene), Texas Coastal Plain". Bulletin of the Florida Museum of Natural History. 42 (1): 1–80. Bibcode:1999BFMNH..42....1A. doi:10.58782/flmnh.xmof4757. ISSN 2373-9991.