The giant bird Gastornis hunting a Leptictidium in dense forest


Gastornis was a giant of its time, one of the largest animals of the Eocene at two metres tall. It is thought to have been a predator, because its huge beak would have been far too powerful for simply crushing nuts and other vegetation, and it also had impressive talons on its toes. Its size and heavy build show that it can't have been a fast runner, so it probably ambushed prey. Gastornis was formerly known as diatryma, as fossils found in the USA had been given that name before they were identified as being the same species. Gastornis fossils are common at the site of Geiseltal, Germany and in the USA.

Scientific name: Gastornis

Rank: Genus

Common names:

  • Diatyrma,
  • Gaston's bird

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Additional data source: Animal Diversity Web

When they lived

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


  1. Life
  2. Animals
  3. Vertebrates
  4. Birds
  5. Gastornithiformes
  6. Gastornithidae
  7. Gastornis

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