Gastornis/Diatryma By: Ryan Gregoire Special Topics in Geology

Description/ Ecology  Gastornis measured about 1.75 Meters tall and weighed up to 600 pounds  It has a large beak with a hook suggesting it was carnivorous  The environment that Gastornis lived in had large portions of dense forest and a moist subtropical climate. Gastornis also lived in lush grasslands in North America.

Geography/ More environment  North America and Europe were still rather close, that’s why fossil records are found on both continents  They lived during the Paleocene- Eocene periods in the Cenozoic Era

Scientific Debates  There has been debate about whether Diatryma’s were carnivores or herbivores, using their large beaks for cracking nuts or strangling pray.  In 1991 Lawrence Wittmer and Kenneth Rose studied the jaw, they decided that the birds were carnivorous, hunting and eating small animals. Given it’s size Gastornis must have been a silent but deadly hunter in the thick forests surrounding its habitat

Diatryma A reconstruction of Diatryma based on fossils found in North America and Western Europe. The bird reached up to 9 feet in height and lived in Eocene grasslands. It is chasing a oreodont artiodactyl whose short legs were no match for the birds speed.

How it Eats  One hypothesis is that Diatryma used its enormous beak to kill prey, gripping an animal in its beak to paralyze it and then shaking its head to break the prey's spine. Much like a modern day tiger or lion.  Eats mostly large mammals and small nuts, such as animals like today’s horses  The closest living animal would be moorhens.

 This Diatryma bones and reconstruction was found In the Willwood Formation in Bighorn County, Wyoming the bones date back to about 55 million years ago.

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