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Beauty or brains? The braincase of Pachyrhinosaurus perotorum and its utility for species-level distinction in the centrosaurine ceratopsid Pachyrhinosaurus

  • Ronald S. Tykoski (a1) and Anthony R. Fiorillo (a1)
Abstract

The centrosaurine ceratopsid taxon Pachyrhinosaurus is the most speciose of centrosaurines, being represented by at least three species (P. canadensis, P. lakustai, and the recently described P. perotorum) from the late Campanian and early Maastrichtian of North America. The species are readily distinguished from one another by details of easily visible cranio-facial and frill ornamentation, features commonly used to differentiate ceratopsid taxa. Braincase material is also known for all three taxa. We describe the braincase of P. perotorum based on specimens from the Kikak–Tegoseak Quarry of the North Slope of Alaska. We then compare it to braincase and endocranial descriptions of the other Pachyrhinosaurus taxa to test whether there may be useful species-level differences present in these robust parts of the ceratopsid skull. Braincase morphology, including cranial nerve paths through the braincase walls in P. lakustai and P. perotorum, were found to be very similar. Two potential diagnostic differences between taxa were found, although tests based on larger sample sizes will be necessary to verify them. This reinforces the importance of highly visual cranio-facial and frill ornamentation as the best tool for species recognition and phylogenetic reconstruction in ceratopsid dinosaurs.

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Brouwers, E. M., Clemens, W. A., Spicer, R. A., Ager, T. A., Carter, L. D. & Sliter, W. V. 1987. Dinosaurs on the North Slope, Alaska: high latitude, latest Cretaceous environments. Science 237 (4822), 1608–10.
Brown, B. 1914. Anchiceratops, a new genus of horned dinosaurs from the Edmonton Cretaceous of Alberta. With discussion of the origin of the Ceratopsian crest and the braincases of Anchiceratops and Trachodon. Bulletin of the American Museum of Natural History 33, 539–48.
Brown, B. & Schlaikjer, E. M. 1940. The structure and relationships of Protoceratops. Annals of the New York Academy of Sciences 40, 133266.
Brown, C. M. & Druckenmiller, P. 2011. Basal ornithopod (Dinosauria: Ornithischia) teeth from the Prince Creek Formation (early Maastrichtian) of Alaska. Canadian Journal of Earth Sciences 48 (9), 1342–54.
Clemens, W. A. & Nelms, L. G. 1993. Paleoecological implications of Alaskan terrestral vertebrate fauna in latest Cretaceous time at high paleolatitudes. Geology 21 (6), 503–06.
Currie, P. J., Langston, W. Jr. & Tanke, D. H. 2008. A new horned dinosaur from an Upper Cretaceous bone bed in Alberta. Ottawa: NRC Research Press. 144 pp.
Davies, K. 1987. Duck-billed dinosaurs (Hadrosauridae: Ornithischia) from the North Slope of Alaska. Journal of Paleontology 61 (1), 198200.
Dodson, P., Forster, C. A. & Sampson, S. D. 2004. Ceratopsidae. In Weishampel, D. B., Dodson, P. & Osmolska, H. (eds) The Dinosauria (2nd edn), 494513. Berkeley: University of California Press.
Farke, A. A., Ryan, M. J., Barrett, P. M., Tanke, D. H., Braman, D. R., Loewen, M. A. & Graham, M. R. 2011. A new centrosaurine from the Late Cretaceous of Alberta, Canada, and the evolution of parietal ornamentation in horned dinosaurs. Acta Palaeontologica Polonica 56 (4), 691702.
Fiorillo, A. R. 2004. The dinosaurs of arctic Alaska. Scientific American 291, 8491.
Fiorillo, A. R. 2008a. On the occurrence of exceptionally large teeth of Troodon (Dinosauria:Saurischia) from the Late Cretaceous of northern Alaska. PALAIOS 23 (5), 322–28.
Fiorillo, A. R. 2008b. Cretaceous dinosaurs of Alaska: Implications for the origins of Beringia. In Blodgett, R. B. & Stanley, G. (eds) The Terrane Puzzle: new perspectives on paleontology and stratigraphy from the North American Cordillera. Geological Society of America Special Paper 442, 313–26. Boulder, Colorado & Lawrence, Kansas: Geological Society of America & University of Kansas Press.
Fiorillo, A. R., Tykoski, R. S., Currie, P. J., McCarthy, P. J. & Flaig, P. 2009. Description of Two Partial Troodon Braincases from the Prince Creek Formation (Upper Cretaceous), North Slope Alaska. Journal of Vertebrate Paleontology 29 (1), 178–87.
Fiorillo, A. R., McCarthy, P. J., Flaig, P. P., Brandlen, E., Norton, D. W., Zippi, P., Jacobs, L. & Gangloff, R. A. 2010a. Paleontology and paleoenvironmental interpretation of the Kikak-Tegoseak Quarry (Prince Creek Formation: Late Cretaceous), northern Alaska: a multi-disciplinary study of a high-latitude ceratopsian dinosaur bonebed. In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds.) New Perspective on Horned Dinosaurs, 456–77. Bloomington: Indiana University Press.
Fiorillo, A. R., Decker, P. L., LePain, D. L., Wartes, M. & McCarthy, P. J. 2010b. A probable Neoceratopsian manus track from the Nanushuk Formation (Albian, Northern Alaska). Journal of Iberian Geology 36 (2), 165–74.
Fiorillo, A. R. & Adams, T. L. 2012. A therizinosaur track from the Lower Cantwell Formation (Upper Cretaceous) of Denali National Park, Alaska. PALAIOS 27 (6), 395400.
Fiorillo, A. R. & Gangloff, R. A. 2000. Theropod teeth from the Prince Creek Formation (Cretaceous) of northern Alaska, with speculations on arctic dinosaur paleoecology: Journal of Vertebrate Paleontology 20 (4), 675–82.
Fiorillo, A. R. & Gangloff, R. A. 2001. The caribou migration model for Arctic hadrosaurs (Ornithischia: Dinosauria): a reassessment. Historical Biology 15 (4), 323–34.
Fiorillo, A. R. & Tykoski, R. S. 2012. A new Maastrichtian species of the centrosaurine ceratopsid Pachyrhinosaurus from the North Slope (Prince Creek Formation: Maastrichtian) of Alaska. Acta Palaeontologica Polonica 57 (3), 561–73.
Flaig, P., McCarthy, P. J. & Fiorillo, A. R. 2011. A tidally-influenced, high-latitude alluvial/coastal plain: the Late Cretaceous (Maastrichtian) Prince Creek Formation, North Slope, Alaska. In Davidson, S. K., Leleu, S. & North, C. P. (eds) From River to Rock Record: The Preservation of Fluvial Sediments and their Subsequent Interpretation. SEPM Special Publication 97, 233–64. Tulsa, Oklahoma: Society for Sedimentary Geology.
Forster, C. A. 1996. New information on the skull of Triceratops. Journal of Vertebrate Paleontology 16 (2), 246–58.
Gangloff, R. A., Fiorillo, A. R. & Norton, D. W. 2005. The first pachycephalosaurine (Dinosauria) from the Paleo-Arctic and its paleogeographic implications. Journal of Paleontology 79 (5), 9971001.
Gangloff, R. A. & Fiorillo, A. R. 2010. Taphonomy and paleoecology of a bonebed from the Prince Creek Formation, North Slope, Alaska. PALAIOS 25 (5), 299317.
Hatcher, J. B., Marsh, O. C. & Lull, R. S. 1907. The Ceratopsia. Monographs of the United States Geological Survey XLIX. Washington, DC: US Government Printing Office.
Hay, O. P. 1909. On the skull and the brain of Triceratops with notes on the brain-cases of Iguanodon and Megalosaurus. Proceedings of the United States National Museum XXXVI (1660), 95108.
Kirkland, J. I. & DeBlieux, D. D. 2010. New basal centrosaurine ceratopsian skulls from the Wahweap Formation (Middle Campanian), Grand Staircase-Escalante National Monument, southern Utah. In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds) New Perspective on Horned Dinosaurs, 117–40. Bloomington: Indiana University Press.
Langston, W. Jr. 1967. The thick-headed ceratopsian dinosaur Pachyrhinosaurus (Reptilia: Ornithischia), from the Edmonton Formation near Drumheller, Canada. Canadian Journal of Earth Sciences 4, 171–86.
Langston, W. Jr. 1968. A further note on Pachyrhinosaurus (Reptilia: Ceratopsia). Journal of Paleontology 42 (5), 1303–04.
Langston, W. Jr. 1975. The ceratopsian dinosaurs and associated lower vertebrates from the St. Mary River Formation (Maestrichtian) at Scabby Butte, southern Alberta. Canadian Journal of Earth Sciences 12, 1576–608.
Lawver, L. A., Grantz, A. & Gahagan, L. M. 2002. Plate kinematic evolution of the present Arctic Region Since the Ordovician. In Miller, E. L., Grantz, A. & Klemperer, S. L. (eds) Tectonic Evolution of the Bering Shelf–Chukchi Sea-Arctic Margin and Adjacent Landmasses. Geological Society of America Special Paper 360, 333–58. Boulder, Colorado & Lawrence, Kansas: Geological Society of America & University of Kansas Press.
Loewen, M. A., Sampson, S. D., Lund, E. K., Farke, A. A., Aguillón-Martínez, M. C., de Leon, C. A., Rodríguez-de la Rosa, R. A., Getty, M. A. & Eberth, D. A. 2010. Horned dinosaurs (Ornithischia: Ceratopsidae) from the Upper Cretaceous (Campanian) Cerro del Pueblo Formation, Coahuila, Mexico. In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds) New Perspectives on Horned Dinosaurs. 99116. Bloomington: Indiana University Press.
McDonald, A. T. & Horner, J. R. 2010. New material of “Styracosaurusovatus from the Two Medicine Formation of Montana. In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds) New Perspective on Horned Dinosaurs, 156–68. Bloomington: Indiana University Press.
Marsh, O. C. 1891. The gigantic Ceratopsidae, or horned Dinosaurs, of North America. American Journal of Science (Series III) 41, 168–78.
Marsh, O. C. 1896. The dinosaurs of North America. United States Geological Survey, 16th Annual Report, 1894–95 55, 133244.
Ott, C. J. & Larson, P. L. 2010. A new, small ceratopsian dinosaur from the Latest Cretaceous Hell Creek Formation, northwest South Dakota, United States: a preliminary description. In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds.) New Perspective on Horned Dinosaurs, 203–18. Bloomington: Indiana University Press.
Parrish, M. J., Parrish, J. T., Hutchinson, J. H. & Spicer, R. A. 1987. Late Cretaceous vertebrate fossils from the North Slope of Alaska and implications for dinosaur ecology. PALAIOS 2 (4), 377–89.
Rasband, W. S. 1997–2011. ImageJ. Bethesda, Maryland, USA: U. S. National Institutes of Health. http://imagej.nih.gov/ij/
Rich, T. H., Vickers-Rich, P. & Gangloff, R. A. 2002. Polar dinosaurs. Science 295, 979–80.
Russell, D. A. 1993. The role of central Asia in dinosaurian biogeography. Canadian Journal of Earth Sciences 30 (10), 2002–12.
Ryan, M. J. 2007. A new basal centrosaurine ceratopsid from the Oldman Formation, southeastern Alberta. Journal of Paleontology 81 (2), 376–96.
Ryan, M. J. & Russell, A. P. 2005. A new centrosaurine ceratopsid from the Oldman Formation of Alberta and its implcations for centrosaurine taxonomy and systematics. Canadian Journal of Earth Sciences 42 (7), 1369–87.
Ryan, M. J., Eberth, D. A., Brinkman, D. B., Currie, P. J. & Tanke, D. H. 2010. A new Pachyrhinosaurus-like ceratopsid from the Upper Dinosaur Park Formation (Late Campanian) of southern Alberta, Canada. In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds) New Perspective on Horned Dinosaurs, 141–55. Bloomington: Indiana University Press.
Sampson, S. D. 1995. Two new horned dinosaurs from the Upper Cretaceous Two Medicine Formation of Montana; with a phylogenetic analysis of the centrosaurinae (Ornithischia: Ceratopsidae). Journal of Vertebrate Paleontology 15 (4), 743–60.
Sampson, S. D., Ryan, M. J. & Tanke, D. H. 1997. Craniofacial ontogeny in centrosaurine dinosaurs (Ornithischia: Ceratopsidae): taxonomic and behavioral implications. Zoological Journal of the Linnean Society 121 (3), 293337.
Sampson, S. D., Loewen, M. A., Farke, A. A., Roberts, E. M., Forster, C. A., Smith, J. A. & Titus, A. L. 2010. New horned dinosaurs from Utah provide evidence for intra-continental dinosaur endemism. PLoS ONE 5(9), e12292. doi:10.1371/journal.pone.0012292.
Sampson, S. D. & Loewen, M. A. 2010. Unraveling a radiation: a review of the diversity, stratigraphic distribution, biogeography, and evolution of horned dinosaurs (Ornithischia: Ceratopsidae). In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds) New Perspective on Horned Dinosaurs, 405–27. Bloomington: Indiana University Press.
Sereno, P. 2000. The fossil record, systematics and evolution of pachycephalosaurs and ceratopsians from Asia. In Benton, M. J., Shishkin, M. A., Unwin, D. M. & Kurochkin, E. N. (eds) The age of dinosaurs in Russia and Mongolia, 480516. Cambridge, UK: Cambridge University Press.
Sternberg, C. M. 1950. Pachyrhinosaurus canadensis, representing a new family of the Ceratopsia, from southern Alberta. National Museum of Canada, Bulletin 118, 109–20.
Sullivan, R. M. & Lucas, S. G.. 2010. A new chasmosaurine (Ceratopsidae, Dinosauria) from the Upper Cretaceous Ojo Alamo Formation (Naasoibito Member), San Juan Basin, New Mexico. In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds) New Perspective on Horned Dinosaurs, 169–80. Bloomington: Indiana University Press.
Witmer, L. M. & Ridgely, R. C. 2008. Structure of the brain cavity and inner ear of the centrosaurine ceratopsid dinosaur Pachyrhinosaurus based on CT scanning and 3D visualization. In Currie, P. J., Langston, W. Jr., & Tanke, D. H. (eds) A new horned dinosaur from an Upper Cretaceous bone bed in Alberta, 117–44. Ottawa: NRC Research Press.
Witte, K. W., Stone, D. B. & Mull, C. G. 1987. Paleomagnetism, paleobotany, and paleogeography of the Cretaceous, North Slope, Alaska. In Tailleur, I. & Weimer, P. (eds) Alaska North Slope Geology, 571–79. Bakersfield: The Pacific Section, Society of Economic Paleontologists and Mineralogists and the Alaska Geological Society 1.
Wolfe, D. G. & Kirkland, J. I. 1998. Zuniceratops christopheri n. gen. & n. sp., a ceratopsian dinosaur from the Moreno Hill Formation (Cretaceous, Turonian) of west-central New Mexico. In Lucas, S. G., Kirkland, J. I. & Estep, J. W. (eds) Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin 14, 303–17. Albuquerque: New Mexico Museum of Natural History and Science. 330 pp.
Wu, X.-c., Brinkman, D. B., Eberth, D. A. & Braman, D. R. 2007. A new ceratopsid dinosaur (Ornthischia) from the uppermost Horseshoe Canyon Formation (upper Maastrichtian), Alberta, Canada. Canadian Journal of Earth Sciences 44 (9), 1243–65.
Xu, X., Wang, K., Zhao, X. & Li, D. 2010. First ceratopsid dinosaur from China and its biogeographical implications. Chinese Science Bulletin 55 (16), 1631–35.
Zanno, L. 2010. A taxonomic and phylogenetic re-evaluation of Therizinosauria (Dinosauria: Maniraptora). Journal of Systematic Palaeontology 8 (4), 503–43.
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