page_title: Deinocheirus
section_title: Palaeopathology
hierarchical_section_title: Deinocheirus / Paleobiology / Palaeopathology
caption_attribution_description: English: Two Tarbosaurus (on each side) attacking a Deinocheirus (center). Bottom&#160;: two smaller Breviceratops .Français&#160;: Deux Tarbosaurus (de chaque côté) attaquant un Deinocheirus (centre). En bas&#160;: deux plus petits Breviceratops .
context_page_description: Deinocheirus is a genus of large ornithomimosaur that lived during the Late Cretaceous around 70 million years ago. In 1965, a pair of large arms, shoulder girdles, and a few other bones of a new dinosaur were first discovered in the Nemegt Formation of Mongolia. In 1970, this specimen became the holotype of the only species within the genus, Deinocheirus mirificus; the genus name is Greek for "horrible hand". No further remains were discovered for almost fifty years, and its nature remained a mystery. Two more complete specimens were described in 2014, which shed light on many aspects of the animal. Parts of these new specimens had been looted from Mongolia some years before, but were repatriated in 2014.
  Deinocheirus was an unusual ornithomimosaur, the largest of the clade at 11 m long, and weighing 6.4 t. Though it was a bulky animal, it had many hollow bones which saved weight. The arms were among the largest of any bipedal dinosaur at 2.4 m long, with large, blunt claws on its three-fingered hands. The legs were relatively short, and bore blunt claws. Its vertebrae had tall neural spines that formed a "sail" along its back.
context_section_description: Osmólska and Roniewicz reported palaeopathologies in the holotype specimen such as abnormal pits, grooves and tubercles on the first and second phalanx of the left second finger that may have been the result of injuries to the joint between the two bones. The damage may have caused changes to the arrangement of ligaments of muscles. The two coracoids are also differently developed. A rib of specimen MPC-D 100/127 shows a healed trauma which has remodelled the bone. In 2012, bite marks on two gastralia of the holotype specimen were reported. The size and shape of the bite marks match the teeth of Tarbosaurus, the largest known predator from the Nemegt Formation. Various types of feeding traces were identified; punctures, gouges, striae, fragmentary teeth, and combinations of the above marks. The bite marks probably represent feeding behaviour instead of aggression between the species, and the fact that bite marks were not found elsewhere on the body indicates the predator focused on internal organs. Tarbosaurus bite marks have also been identified on hadrosaur and sauropod fossils, but theropod bite marks on bones of other theropods are very rare in the fossil record.
caption: Restoration of two Tarbosaurus attacking a Deinocheirus; bite marks show that this tyrannosaur fed on Deinocheirus
exif: {"Image XResolution": "96", "Image YResolution": "96", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "paint.net 4.1.1"}