Oviraptor

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{{Taxobox | color = pink | name = Oviraptor | status = Conservation status: Fossil | regnum = Animalia | phylum = Chordata | classis = Sauropsida | superordo = Dinosauria | ordo = Saurischia | unranked_familia = Oviraptorosauria | familia = Oviraptoridae | genus = Oviraptor | species = O. philoceratops | binomial = Oviraptor philoceratops | binomial_authority = Osborn, 1924 }}

Oviraptor was a small Mongolian theropod dinosaur, first discovered by legendary paleontologist Roy Chapman Andrews and first described by Henry Fairfield Osborn in 1924. Its name is Latin for "egg thief", referring to the fact that the first fossil specimen was discovered next to a pile of what were thought to be Protoceratops eggs. The specific name philoceratops means "lover of ceratopsians". However, it is now believed that the eggs belonged to this genus itself, and that it was actually brooding its eggs, based on discoveries of a related animal called Citipati, named by Clark, Makovicky, and Barsbold in 2000. Oviraptor forms the basis of a group called Oviraptoridae, named by Barsbold Rinchen in 1976. Barsbold then used the name to coin a group called Oviraptorosauria.

Diet

Oviraptor may have eaten eggs. However, in 1977, Barsbold argued that the strength of its beak would indicate that it was strong enough to break the shells of mollusks such as clams, which are found in the same formation as Oviraptor. The idea of a crushing jaw was first proposed by H. F. Osborn, who believed that the toothless beak in the original skull, together with an extension of several bones below the jaw from the palate, would have made an "egg-piercing" tool. Theses bones, known as ectopterygoids, are not actually part of an egg-piercing structure, and what Osborn found was incorrect. However, several skulls of oviraptorids, found in the 1950s and 1960s and described in the 1970s and 1980s, show that they are indeed egg-piercing bones, as part of the main upper jaw bone or maxilla, which converge in the middle to form a pair of prongs. The rest of the bony palate, unlike all other dinosaurs, is extended below the jaw line and would have pushed into the space between the toothless lower jaws. A rhamphotheca, or the keratin forming the beaks of birds, covered the edges of upper and lower beaks and probably the palate, as proposed by Barsbold and Osborn.

Age

Oviraptor lived in the late Cretaceous Period, during the Santonian stage, and may have lived in an earlier stage called the Campanian, between 80 to 70 million years ago; it comes almost exclusively from the Djadokhta Formation of Mongolia, as well as the northeast region of the Neimongol Autonomous Region of China, in an area called Bayan Mandahu. Relatives of Oviraptor include Ingenia and Chirostenotes.

Appearance

Oviraptor was one of the most bird-like of the non-avian dinosaurs. Its rib cage, in particular, displayed several features that are typical of birds, including a set of processes on each rib that would have kept the rib cage rigid. A relative of Oviraptor called Nomingia was found with a pygostyle, which is a set of fused vertebrae that would later help support the tail feathers of birds.

Oviraptor is traditionally depicted with a distinctive crest similar to that of the cassowary. However, re-examination of several oviraptorids (Clark, Norell & Barsbold, 2001) show that this well-known dinosaur is actually a species of Citipati, a relative of Oviraptor. It is likely that Oviraptor did have a crest, but its exact size and shape are unknown due to crushing in the skull specimens.

Oviraptor in fiction

James Guerney in his book Dinotopia conceived of an animal based on Oviraptor. Because some felt it was no longer considered a predator of eggs, he renamed the animal "Ovinutrix", which means "egg nurse". However, this renaming would have been unnecessary, for even if the animal brooded its own eggs, this does not mean that it did not eat the eggs of other animals.

Oviraptor appeared in the game Dino Stalker. In the game it burrowed through sand to surprise its enemies, it also spat poison; this is, of course, purely for gameplay.de:Oviraptor es:Oviraptor fr:Oviraptor nl:Oviraptor ja:オヴィラプトル pl:Owiraptor pt:Oviráptor sk:Oviraptor