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Function and evolution of ankylosaur dermal armor

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Ankylosaurs have spike−, plate−, and club−shaped osteoderms probably used as defensive and/or offensive weapons. Previous studies have proposed the evolution and function of small ankylosaur osteoderms, but histological variations in their defensive weapons are little known. Here, we provide comparisons of the internal structures in defensive weapons of ankylosaurs, which shed light on understanding their evolutionary history and function. Histological features of spikes, plates, and clubs are similar to those of small osteoderms in having thin compact bone, thick cancellous bone with large vascular canals, and abundant collagen fibers. A previous study demonstrated that each of the three groups of ankylosaurs (the Polacanthidae, Nodosauridae, and Ankylosauridae) have distinct arrangements of collagen fibers in small osteoderms. This study shows that spikes and clubs of ankylosaurs maintain the same characteristic features for each group despite the differences in shapes and sizes. These histological similarities suggest that various types of osteoderms in ankylosaurs retained the thin compact bone and abundant fiber structures of the small osteoderms during their evolution. Polacanthid spikes show thin compact bone, with less collagen fibers than in spikes of nodosaurids and spikes and clubs of ankylosaurids. Also, ankylosaurid plates with hollow bases are very thin in morphology and show thin compact bone. These results imply that the bone strengths of polacanthid spikes and ankylosaurid plates are lower than spikes and clubs of other ankylosaurs, indicating that they may be used more probably as display and/or thermoregulation rather than as weapons. It is thus probable that ankylosaur armor in general played more than just a defensive role.
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  • Hokkaido University, Sapporo, 060-0810, Japan
  • Arbour V. 2009. Estimating impact forces of tail club strikes by ankylosaurid dinosaurs. PLoS ONE 4: e6738.
  • Arbor, V. and Snively, E. 2009. Finite element analyses of ankylosaurid dinosaur tail club impacts. The Anatomical Record 292: 1412–1426.
  • Bakker, R.T. 1986. Dinosaur Heresies. 481 pp. William Morrow, New York.
  • Barrett, P.M., Clarke, J.B., Brinkman, D.B., Chapman, S.D., and Ensom, P.C. 2002. Morphology, histology and identification of the “granicones” from the Purbeck Limestone Formation (Lower Cretaceous: Berriasian) of Dorset, southern England. Cretaceous Research 23: 279–295.
  • Blows, W.T. 1987. The armoured dinosaur Polacanthus foxii from the Lower Cretaceous of the Isle of Wight. Palaeontology 30: 557–580.
  • Blows, W.T. 2001. Dermal armor of the polacanthine ankylosaurs. In: K. Carpenter (ed.), The Armored Dinosaurs, 363–385. Indiana University Press, Bloomington.
  • Buffrénil, V. de, Farlow, J.O., and de Ricqlès, A. 1986. Growth and function of Stegosaurus plates: evidence from bone histology. Paleobiology 12: 459–473.
  • Carpenter, K. 1982. Skeletal and dermal armor reconstructions of Euoplocephalus tutus (Ornithischia: Ankylosauridae) from the Late Cretaceous Oldman Formation of Alberta. Canadian Journal of Earth Sciences 19: 689–697.
  • Carpenter, K. 1997. Ankylosaurs. In: J.O. Farlow and M.K. Brett−Surman (eds.), The Complete Dinosaur, 307–316. Indiana University Press, Bloomington.
  • Carpenter, K. 1998. Armor of Stegosaurus stenops, and the taphonomic history of a new specimen from Garden Park, Colorado. Modern Geology 23: 127–144.
  • Carpenter, K. 2001. Phylogenetic analysis of the Ankylosauria. In: K. Carpenter (ed.), The Armored Dinosaurs, 455–483. Indiana University Press, Bloomington.
  • Carpenter, K. 2004. Redescription of Ankylosaurus magniventris Brown 1908 (Ankylosauridae) from the Upper Cretaceous of the Western Interior of North America. Canadian Journal of Earth Sciences 41: 961–981.
  • Carpenter, K. and Breithaupt, B. 1986. Latest Cretaceous occurrence of nodosaurid ankylosaurs (Dinosauria: Ornithischia) in western North America and the gradual extinction of the dinosaurs. Journal of Vertebrate Paleontology 6: 251–257.
  • Carpenter, K., Miles, C., and Cloward, K. 1998. Skull of a Jurassic ankylosaur (Dinosauria). Nature 393: 782–783.
  • Carpenter, K., Sanders, F., McWhinny, L.A., and Wood, L. 2005. Evidence for predatory−prey relationships. Examples for Allosaurus and Stegosaurus. In: K. Carpenter (ed.), The Carnivorous Dinosaurs, 325–350. Indiana University Press, Bloomington.
  • Castanet, J., Francillon−Vieillot, H., Meunier, F. J., and de Ricqlès, A. 1993. Bone and individual aging. In: B.K. Hall (ed.), Bone, Vol. 7. Bone Growth—B, 245–283. CRC Press, Boca Raton.
  • Coombs, W. 1971. The Ankylosauria. 487 pp. Columbia University, New York.
  • Coombs, W. 1978a. The families of the ornithischian dinosaur order Ankylosauria. Journal of Paleontology 21: 143–170.
  • Coombs, W. 1978b. Forelimb muscles of the Ankylosauria (Reptilia: Ornithischia). Journal of Paleontology 52: 642–658.
  • Coombs, W. 1979. Osteology and myology of the hindlimb in the Ankylosauria (Reptilia, Ornithischia). Journal of Paleontology 53: 666–684.
  • Coombs, W.P. 1986. A juvenile ankylosaur referable to the genus Euoplocephalus (Reptilia: Ornithischia). Journal of Vertebrate Paleontology 6: 162–173.
  • Coombs, W.P. 1995. Ankylosaurian tail clubs of middle Campanian to early Maastrichtian age from western North America, with description of a tiny club from Alberta and discussion of tail orientation and tail club function. Canadian Journal of Earth Sciences 32: 902–912.
  • Coombs, W. and Maryańska, T. 1990, Ankylosauria. In: D. Weishampel, P. Dodson, and H. Osmolska (eds.), The Dinosauria, 456–483. University of California Press, Berkeley.
  • Coombs, W.P. Jr. 1979. Osteology and myology of the Hindlimb in the Ankylosauria (Reptilia, Ornithischia). Journal of Paleontology 52: 642–658.
  • Currie, J.P. 1991. The Sino/Canadian dinosaur expeditions 1986–1990: Geotimes April: 19–21.
  • Curry, K.A. 1999. Ontogenetic histology of Apatosaurus (Dinosauria: Sauropoda): new insights on growth rates and longevity. Journal of Vertebrate Paleontology 19: 654–665.
  • Ford, T.L. 2000. A review of ankylosaur osteoderms from New Mexico and a preliminary review of ankylosaur armor. New Mexico Museum of Natural History and Science Bulletin 17: 157–176.
  • Francillon−Vieillot, H., de Buffrénil, V., Castanet, J., Géraudie, J., Meunier, F. J., Sire, J. Y., Zylberberg, L., and de Ricqlès, A. 1990. Microstructure and mineralization of vertebrate skeletal tissues. In: J. G. Carter (ed.), Skeletal Biomineralization: Patterns, Processes and Evolutionary Trends, Vol. 1, 471–530. Van Nostrand Reinhold, New York.
  • Hayashi, S. and Carpenter, K. 2006. Osteoderm histology of Stegosaurus stenops (Ornithischia: Thyreophora): implications for plate and spike growth. Journal of Vertebrate Paleontology 26 (Supplement to No. 3): 73A.
  • Hayashi, S., Carpenter, K., and Suzuki, D. 2009. Different growth patterns between the skeleton and osteoderm of Stegosaurus (Ornithischia: Thyreophora). Journal of Vertebrate Paleontology 29: 123–131.
  • Hill, V., Witmer, L., and Norell, M. 2003. A new specimen of Pinacosaurus grangeri (Dinosauria: Ornithischia) from the Late Cretaceous of Mongolia: ontogeny and phylogeny of ankylosaurs. American Museum Novitates 3395: 1–29.
  • Kilbourne, B. and Carpenter, K. 2005. Redescription of Gargoyleosaurus parkpinorum, a polacanthid ankylosaur from the Upper Jurassic of Albany Country, Wyoming. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 237: 111–160.
  • Kirkland, J.I. 1998. A polacanthine ankylosaur (Ornithischia:Dinosauria) from the Early Cretaceous (Barremian) of Eastern Utah. In: S.G. Lucas, J.I. Kirkland, and J.W. Estep (eds.), Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin 14: 271–281.
  • Klein, N. and Sander, P.M. 2007. Bone histology and growth of the prosauropod Plateosaurus engelhardti Meyer, 1837 from the Norian bonebeds of Trossingen (Germany) and Frick (Switzerland). Special Papers in Palaeontology 77: 169–206.
  • Main, R.P., de Ricqlès, A., Horner, J.R., and Padian, K. 2005. The evolution and function of thyreophoran dinosaur scutes: implications for plate function in stegosaurs. Paleobiology 31: 291–314.;2
  • Maryańska, T. 1977. Ankylosauridae (Dinosauria) from Mongolia. Palaeontologia Polonica 37: 85–151.
  • Pisani, D., Yates, A.M., Langer, M.C., and Benton, M.J. 2002. A genus−level supertree of the Dinosauria. Proceedings of the Royal Society of London, Series B 269: 915–921.
  • Sander, P.M. 2000. Long bone histology of the Tendaguru sauropods: implications for growth and biology.Paleobiology 26: 466–488.;2
  • Sander, P.M., Mateus, O., Laven, T., and Knötschke, N. 2006. Bone histology indicates insular dwarfism in a new Late Jurassic sauropod dinosaur. Nature 441: 739–741.
  • Scheyer, T., and Sander, P.M. 2004. Histology of ankylosaur osteoderms: implications for systematics and function. Journal of Vertebrate Paleontology 24: 874–893.−4634(2004)024%5B0874:HOAOIF%5D2.0.CO;2
  • Seidel, M. 1979. The osteoderms of the American alligator and their functional significance. Herpetologica 35: 375–380.
  • Suzuki, D., Murakami, G., and Minoura, N. 2002. Histology of the bonetendon interfaces of limb muscles in lizards. Annals of Anatomy 184: 363–377.
  • Suzuki, D., Murakami, G., and Minoura, N. 2003. Crocodilian bone−tendon and bone−ligament interfaces. Annals of Anatomy 185: 425–433.
  • Thulborn, T. 1993. Mimicry in ankylosaurid dinosaurs. Record of the South Australian Museum 27: 151–158.
  • Vickaryous, M. and Hall, B. 2008. Development of the dermal skeleton in Alligator mississippiensis (Archosauria, Crocodylia) with comments on the homology of the osteoderms. Journal of Morphology 269: 398–422.
  • Vickaryous, M. and Sire, J.−Y. 2009. The integument skeleton of tetrapods: origin, evolution, and development. Journal of Anatomy 214: 407–644.
  • Vickaryous, M., Maryańska, T., and Weishampel, D. 2004. Ankylosauria. In: D. Weishampel, P. Dodson, and H. Osmólska (eds.), The Dinosauria (2nd edition), 427–434. University of California Press, Berkeley.
  • Vickaryous, M., Russell, A., and Curry, P. 2001. Cranial ornamentation of ankylosaurs (Ornithischia: Thyreophora): reappraisal of development hypothesis. In: K. Carpenter (ed.), The Armored Dinosaurs, 318–340. Indiana University Press, Bloomington.
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