Oviraptor Palates

Reconstructed Oviraptor skull be Jaime A. Headden.

Oviraptors are notoriously known for the revision on their feeding habits. Originally thought to have been obligate egg-eaters, the findings that associated eggs were actually their own has sparked controversy about their actual feeding habits. Some have suggested a mollusc based diet, others an omnivorous but fruit and seed based diet.

A relatively under discussed part of this debate revolves around their palate. Oviraptors possess two projections that end up in tooth-like structures. When they were assumed to be egg eaters they were considered vital in piercing egg shells (Osborn 1924), and Barsbold suggested that they could have been used to pry mollusc shells open (Barsbold 1977). Other studies have found that the jaws of oviraptorids were more suited for shearing rather than crushing, but they have since been rejected (Funston et al 2018). Still, these newer studies don’t explore much in the way of function for the strange palate.

A possible explanation is that they were used to manipulate objects in the mouth, perhaps keeping seeds and fruits in place while the beak crushed them. Given the presence of a lizard in one specimen’s innwards (Norell et al 1995), they could’ve have function like the raised palate of predatory birds, though in that case they would have been more raptorial than recent studies on their diet suggest.

Ultimately, this seems to parallel how some mammals with “herbivorous dentition” are in fact more carnivorous than their anatomy suggests (Hu Y et al 2009), only perhaps in reverse.

Needless to say, more studies are welcome.

References

Osborn, H. F. (1924). “Three new Theropoda, Protoceratops zone, central Mongolia”. American Museum Novitates (144): 1−12. hdl:2246/3223. OCLC 40272928.

Barsbold, R. (1977). “Kinetism and peculiarity of the jaw apparatus of oviraptors (Theropoda, Saurischia)”. Soviet-Mongolian Paleontological Expedition, Trudy. 4: 37−47

Funston, G. F.; Mendonca, S. E.; Currie, P. J.; Barsbold, R.; Barsbold, R. (2018). “Oviraptorosaur anatomy, diversity and ecology in the Nemegt Basin”. Palaeogeography, Palaeoclimatology, Palaeoecology. 494: 101−120. Bibcode:2018PPP…494..101F. doi:10.1016/j.palaeo.2017.10.023.

Norell, M. A.; Gaffney, E. S.; Dingus, L. (1995). Discovering Dinosaurs In the American Museum of Natural History. Knopf Inc. p. 225.

Hu Y, Meng J, Clark JM (2009). “A new Tritylodontid from the Upper Jurassic of Xinjiang, China”. Acta Palaeontologica Polonica. 54 (3): 385–391. doi:10.4202/app.2008.0053.