96
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      First complete sauropod dinosaur skull from the Cretaceous of the Americas and the evolution of sauropod dentition

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Sauropod dinosaur bones are common in Mesozoic terrestrial sediments, but sauropod skulls are exceedingly rare—cranial materials are known for less than one third of sauropod genera and even fewer are known from complete skulls. Here we describe the first complete sauropod skull from the Cretaceous of the Americas, Abydosaurus mcintoshi, n. gen., n. sp., known from 104.46 ± 0.95 Ma (megannum) sediments from Dinosaur National Monument, USA. Abydosaurus shares close ancestry with Brachiosaurus, which appeared in the fossil record ca. 45 million years earlier and had substantially broader teeth. A survey of tooth shape in sauropodomorphs demonstrates that sauropods evolved broad crowns during the Early Jurassic but did not evolve narrow crowns until the Late Jurassic, when they occupied their greatest range of crown breadths. During the Cretaceous, brachiosaurids and other lineages independently underwent a marked diminution in tooth breadth, and before the latest Cretaceous broad-crowned sauropods were extinct on all continental landmasses. Differential survival and diversification of narrow-crowned sauropods in the Late Cretaceous appears to be a directed trend that was not correlated with changes in plant diversity or abundance, but may signal a shift towards elevated tooth replacement rates and high-wear dentition. Sauropods lacked many of the complex herbivorous adaptations present within contemporaneous ornithischian herbivores, such as beaks, cheeks, kinesis, and heterodonty. The spartan design of sauropod skulls may be related to their remarkably small size—sauropod skulls account for only 1/200th of total body volume compared to 1/30th body volume in ornithopod dinosaurs.

          Electronic supplementary material

          The online version of this article (doi:10.1007/s00114-010-0650-6) contains supplementary material, which is available to authorized users.

          Related collections

          Most cited references40

          • Record: found
          • Abstract: found
          • Article: not found

          Phylogenetic variation in the silicon composition of plants.

          Silicon (Si) in plants provides structural support and improves tolerance to diseases, drought and metal toxicity. Shoot Si concentrations are generally considered to be greater in monocotyledonous than in non-monocot plant species. The phylogenetic variation in the shoot Si concentration of plants reported in the primary literature has been quantified. Studies were identified which reported Si concentrations in leaf or non-woody shoot tissues from at least two plant species growing in the same environment. Each study contained at least one species in common with another study. Meta-analysis of the data revealed that, in general, ferns, gymnosperms and angiosperms accumulated less Si in their shoots than non-vascular plant species and horsetails. Within angiosperms and ferns, differences in shoot Si concentration between species grouped by their higher-level phylogenetic position were identified. Within the angiosperms, species from the commelinoid monocot orders Poales and Arecales accumulated substantially more Si in their shoots than species from other monocot clades. A high shoot Si concentration is not a general feature of monocot species. Information on the phylogenetic variation in shoot Si concentration may provide useful palaeoecological and archaeological information, and inform studies of the biogeochemical cycling of Si and those of the molecular genetics of Si uptake and transport in plants.
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            Sauropod dinosaur phylogeny: critique and cladistic analysis

              Bookmark
              • Record: found
              • Abstract: not found
              • Article: not found

              The phylogenetic relationships of sauropod dinosaurs

                Bookmark

                Author and article information

                Contributors
                wilsonja@umich.edu
                Journal
                Naturwissenschaften
                Naturwissenschaften
                Die Naturwissenschaften
                Springer-Verlag (Berlin/Heidelberg )
                0028-1042
                1432-1904
                24 February 2010
                24 February 2010
                April 2010
                : 97
                : 4
                : 379-391
                Affiliations
                [1 ]Dinosaur National Monument, P.O. Box 128, Jensen, UT 84035 USA
                [2 ]Museum of Paleontology and Department of Geological Sciences, Brigham Young University, S-389 ESC, P.O. Box 24606, Provo, UT 84602-4606 USA
                [3 ]Museum of Paleontology and Department of Geological Sciences, University of Michigan, 1109 Geddes Avenue, Ann Arbor, MI 48109-1079 USA
                Article
                650
                10.1007/s00114-010-0650-6
                2841758
                20179896
                6338259d-b790-4441-9945-ef53b6f6f8bd
                © The Author(s) 2010
                History
                : 21 October 2009
                : 15 January 2010
                : 16 January 2010
                Categories
                Original Paper
                Custom metadata
                © Springer-Verlag 2010

                Uncategorized
                cretaceous,sauropoda,north america,tooth shape,dinosauria,herbivory
                Uncategorized
                cretaceous, sauropoda, north america, tooth shape, dinosauria, herbivory

                Comments

                Comment on this article