Diatryma gigantea

Diatryma gigantea is now generally considered a junior synonym of Gastornis, and the species is most commonly referred to as Gastornis gigantea. The name Diatryma was used widely in older literature, especially for North American specimens, but taxonomic revisions have largely unified the genus under Gastornis. Some debate continues about whether North American and European specimens represent the same or closely related species.

This is one of the most debated questions about Diatryma, now called Gastornis. Older interpretations depicted it as a fearsome apex predator that crushed small mammals with its massive beak. More recent studies, including isotope analysis of bone collagen, have suggested it was more likely a herbivore that used its powerful beak to crack tough plant material and seeds.

Diatryma gigantea, now known as Gastornis gigantea, was a massive flightless bird standing close to two meters (about 6.5 feet) tall. It had a deep, powerful beak, strong robust legs, and small vestigial wings. It lived during the early Eocene epoch, roughly 55 to 50 million years ago.

Diatryma gigantea lived in North America during the early Eocene epoch. Fossils have been found in the western United States, particularly in Wyoming. The closely related Gastornis is also well known from Eocene deposits in Europe, including the famous Messel Pit fossil site in Germany.