Hadrosaurs. David A. Eberth

Hadrosaurs - David A. Eberth


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was what we came to Drumheller to report on. It was hadrosaur taxonomy, North American, Asian, South American, and European hadrosaurs, and ornithopod brains. It was also hadrosaur gigantism and age, hadrosaur jaws and herbivory, locomotor mechanics, taphonomy, integument, tracks, and various aspects of development. This was where we thought our discipline was as we began the symposium.

      Eighty-eight percent of the symposium talks (n = 34 talks, 16 posters) fall within the categories discussed here (Braman et al., 2011). Most are taxonomic, phylogenetic, or biogeographic in scope. Another half-dozen or more pertain to functional morphology, growth, and taphonomy – a good sampling of the categories examined here (an acclaim delivered independently twice over – the organizers and I both got it right!).

      Symposium percentages are all the same order of magnitude compared to those obtained for the decade of 2000–2010, but there are several differences. General taxonomic presentations at the symposium were nearly 25% fewer than from 2000–2010, phylogeny was 19% fewer, taphonomy was 15% fewer, biogeography was 28% fewer, paleoecology was 19% fewer, and faunistics was 13% fewer. Soft tissue remained approximately the same. Interestingly, functional morphology was 14% more and growth was 6% more than from the decade of 2000–2010. While it is tempting to assign significance to individual percentages, they are probably no more than sampling errors when comparing a very small number of symposium talks with the projected breakdown of categories for an entire decade.

       WHERE ARE WE GOING?

      I am certainly no prognosticator, even about my own research field. Like all historical sciences, our ability to predict the future is fraught with the kinds of unpredictability that derives from historical contingency. There is little inevitability that guides us in the progress of our science – just as there is little that links the hand-cranked ice-cream maker (1840s) to the electron microscope (1930s), a transition that happened in only nine decades. What about going from the invention of the Band-Aid (1930s) to the home computer in five decades? Who would have predicted these changes?

      But the contents of this volume give an inkling of where we are headed, at least in the short run. I see continued fieldwork, the wellspring of our science. Its direct consequences – new species and taxonomic revisions – are likely to be accompanied by a healthy continuance of studies focused on comparative anatomy, both bony and inferred soft tissue. To do so requires a healthy dose of phylogenetic systematics, which now should be part of everyone’s toolkit. In functional morphology, finite element analyses and tooth-wear studies have appeared on the horizon and I hope these will be coupled with cladistic analyses to produce even more outstanding work. Finally, growth studies are very likely to continue in the future: the small bit of bone given up for a thin-section is bound to yield disproportionately much more subtle and profound information than if it were left with the rest of the bone.

      Still, things do not always work out that way. Contingency makes history messy. Things come out of left field and WHAM! Someone discovers the most amazing specimen or means by which colors can be inferred from skin impressions. All of a sudden, with no way of predicting, we are all scrambling to do research on the melanosomes of what could turn out to be red-, green-, and yellow-striped ornithopods!

       ACKNOWLEDGMENTS

      I thank David Eberth and David Evans for their kind invitation to join them at their fantastic first International Hadrosaur Symposium in Drumheller, Alberta, Canada. Their generosity and that of François Therrien and the other hosts at the Royal Tyrrell Museum of Palaeontology are most commendable. And to throw in a bronze plaque of Corythosaurus intermedius (ROM 845); well, I sure had a good time! I also thank Ali Nabavizadeh and Cat Sartin for their help on and reading of this manuscript and Jack Horner, Cora Jianu, and Pilar Yagüe for their own individual inspirations.

       LITERATURE CITED

      Alexander, R. McN. 1985. Mechanics of posture and gait of some large dinosaurs. Zoological Journal of the Linnean Society 83:1–25.

      Bell, P. 2014. A review of hadrosaurid skin impressions; Chapter 25 in D. A. Eberth, and D. C. Evans (eds.), Hadrosaurs. Indiana University Press, Bloomington, Indiana.

      Benton, M. J. 1985. Mass extinction among non-marine tetrapods. Nature 316:811–814.

      Benton, M. J. 1998. The quality of the fossil record of the vertebrates; pp. 269–303 in S. K. Donovan and C. R. C. Paul (eds.), The Adequacy of the Fossil Record. John Wiley & Sons, New York.

      Braman, D., D. A. Eberth, D. C. Evans, and W. Taylor (compilers). 2011. International Hadrosaur Symposium Abstract Volume. Royal Tyrrell Museum. Drumheller, Alberta. 171 pp.

      Carrano, M. T., C. M. Janis, and J. J. Sepkoski. 1999. Hadrosaurs as ungulate parallels: lost lifestyles and deficient data. Acta Palaeontologia Polonica 44:237–261.

      Casanovas, M. L., X. Pereda-Suberbiola, and D. B. Weishampel. 1999. First lambeosaurine hadrosaurid from Europe: palaeobiogeographical implications. Geological Magazine 136:205–211.

      Chinsamy, A. 1995. Ontogenetic changes in the bone histology of the Late Jurassic ornithopod Dryosaurus lettowvorbecki. Journal of Vertebrate Paleontology 15:96–104.

      Csiki, Z. 1997. Legături paleobiogeografice ale faunei de vertebrate continentale Maastrichtian superioare din Bazinul Haţeg. Nymphaea 23–25:45–68.

      Dodson, P. 1971. Sedimentology and taphonomy of the Oldman Formation (Campanian), Dinosaur Provincial Park, Alberta (Canada). Palaeogeography, Palaeoclimatology, Palaeoecology 10:21–74.

      Dodson, P. 1975. Taxonomic implications of relative growth in lambeosaurine hadrosaurs. Systematic Zoology 24:37–44.

      Dodson, P. 1990. China reaches the top. American Paleontologist 17: online supplement. Available at www.museumoftheearth.org/files/pubtext/supplements/suppl_557c.pdf. Accessed summer 2012.

      Fastovsky, D. E., Y. Huang, J. Hsu, J. Martin-McNaughton, P. M. Sheehan, and D. B. Weishampel. 2004. Shape of Mesozoic dinosaur richness. Geology 32:877–880.

      Galton, P. M. 1972. Classification and evolution of ornithopod dinosaurs. Nature 239:464–466.

      Gilmore, C. W. 1913. A new dinosaur from the Lance Formation of Wyoming. Smithsonian Miscellaneous Collections 61:1–5.

      Horner, J. R., A. de Ricqlès, and K. Padian. 1999. Variation in skeletochronological indicators of the hadrosaurid dinosaur Hypacrosaurus: implications for age assessment of dinosaurs. Paleobiology 25:295–304.

      Horner, J. R., A. de Ricqlès, and K. Padian. 2000. The bone histology of the hadrosaurid dinosaur Maiasaura peeblesorum: growth dynamics and physiology based on an ontogenetic series of skeletal elements. Journal of Vertebrate Paleontology 20:109–123.

      de Lapparent, A. F. 1960. Les dinosauriens du “Continental intercalaire” du Sahara central. Memoire de la Societé geologique de France 88A:1–57.

      Leidy, J. 1858. Hadrosaurus foulkii, a new saurian from the Cretaceous of New Jersey. Proceedings of the Academy of Natural Science of Philadelphia 1859:215–218.

      López-Martinez, N., J. I. Canudo, L. Ardèvol, X. Pereda-Suberbiola, X. Orue-Etxebarria, G. Cuenca-Bescós, J. I. Ruiz-Omeñaca, X. Murilaga, and M. Feist. 2001. New dinosaur sites correlated with upper Maastrichtian pelagic deposits in the Spanish Pyrenees: implications for the dinosaur extinction pattern in Europe. Cretaceous Research 22:41–61.

      Mantell, G. A. 1825. Notice on the Iguanodon, a newly discovered fossil reptile, from the sandstone of the Tilgate Forest, in Sussex. Philosophical Transactions of the Royal Society of London 115:179–186.

      Mantell, G. A. 1844. Medals of Creation. H. G. Bohn, London, U.K., 289 pp.

      Mantell, G. A. 1848. On the structure of the jaws and teeth of the Iguanodon.


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