Anzu

Anzu (after the mythological Sumerian demon Anzû) is a genus of oviraptorosaurian dinosaur from the Late Cretaceous of North America.

Description
Anzu measured 3 or more meters in length and 1.5 meters in height at the hips, and is estimated to have weighed up to 200 kilograms, making it the largest known oviraptorosaur from North America.

Anzu resembled other related oviraptorosaurs, possessing features such as a toothless beak, a head crest, long limbs, and a relatively short tail, but its skeleton is the most complete of any North American oviraptorosaur yet found.

Classification
When first described, Anzu was classified as a caenagnathid oviraptorosaur, and as a possible sister species to Caenagnathus:

History
The known fossils of Anzu were first discovered in the Hell Creek Formation of North and South Dakota during the 1990s. These remains belonged to about four different individuals, and were stored at various museums across the United States.

Three researchers, Emma Schachner of the University of Utah, Matthew Lamanna of the Carnegie Museum of Natural History and Tyler Lyson of the National Museum of Natural History of the Smithsonian Institution, assisted by Hans-Dieter Sues of the Smithsonian, realized in 2006 that the various remains likely belonged to a new species of oviraptorosaur. The creature's bird-like anatomy and occurrence in the Hell Creek Formation led to it being nicknamed the "chicken from hell" by those who were studying it. Lamanna, who named the creature, originally wanted to use either a Latin or Greek version of the words "chicken from hell", but found that the nickname did not work well when translated to those languages. Instead, he named the oviraptorosaur Anzu wyliei, after the feathered demon Anzû from ancient Sumerian mythology. The specific name wyliei honors Wylie J. Tuttle, who is the grandson of donors to the Carnegie Museum of Natural History.

The main fossil remains of Anzu are being held at the Carnegie Museum of Natural History in Pittsburgh, and a cast mounted skeleton is on display there.

Paleoecology
Fossils of Anzu have been found in the Hell Creek Formation, which 66 million years ago was a subtropical floodplain. This meant that the species likely had a significantly different lifestyle from its Asian counterparts, which lived in more arid conditions.

Diet
Anzu was likely an omnivore, as it jaw structure suggests it could eat a variety of different food items such as plants, small animals, and possibly eggs. However, its beak was not as heavily built as in its Asian relatives.

Crest function
Anzu has one of the largest crests in any known oviraptorosaur. It was quite thin and would probably not be able to take much stress. As such, it was most likely used for display.

Pathologies
Some of the fossils of Anzu show evidence of injury, such as a healed broken rib and an arthritic toe likely caused by ripping a tendon away from the bone. It is not certain if these injuries were inflicted by others of its kind or by attacking predators.