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Meeting Program & Abstracts November 5 – 8, 2014 • Estrel Berlin • Berlin, Germany SOCIETY OF VERTEBRATE PALEONTOLOGY NOVEMBER 2014 ABSTRACTS OF PAPERS 74th ANNUAL MEETING Estrel Berlin Berlin, Germany November 5 – 8, 2014 HOST COMMITTEE Nadia Fröbisch; Jörg Fröbisch; Oliver Hampe; Heinrich Mallison; Johannes Müller; Juliane Röhner; Daniela Schwarz; Florian Witzmann EXECUTIVE COMMITTEE Cathy Forster, President; John Long, Vice President; Philip Currie, Past-President; Glenn Storrs, Secretary; Ted Vlamis, Treasurer; Elizabeth Hadly, Member-at-Large; Christian Sidor, Member-at-Large; Paul Barrett, Member-at-Large SYMPOSIUM CONVENORS David W. Bapst; Andreas Christian; Jussi T. Eronen; John R. Hutchinson; Martin Kundrat; Michelle Lawing; Graeme Lloyd; Nicholas J. Matzke; Andrew Milner; P. David Polly; Daniela Schwarz-Wings; Eric Snively; Jean Sébastien Steyer; Florian Witzmann; April Wright PROGRAM COMMITTEE Jonathan Bloch, Co-Chair; Anjali Goswami, Co-Chair; Heather Ahrens; Brian Beatty; Chris Brochu; Richard Butler; Ted Daeschler; David Evans; David Fox; Pat Holroyd; Marc Jones; Christian Kammerer; Matt Lamanna; Erin Maxwell; Josh Miller; Jessica Designed for palaeontology courses in biology and geology departments, this leading Miller-Camp;text will also be of interestKevin to enthusiasts Padian; who Lauren want to experience Sallan; the flavour William of how Sanders; Bruce Shockey; Mary the research is done. The book is strongly phylogenetic, and this makes it a source of currentSilcox; data on vertebrate Michelle evolution. Stocker; Rebecca Terry; Paul Upchurch; Aaron Wood Study aids include key questions, research to be done and recommendations of further reading and websites. EDITORS Read sample content and order at www.wiley.com/go/benton-svpErin Maxwell; Jessica Miller-Camp Save 20%! To benefit from this exclusive discount make sure you quote November 2014—PROGRAM AND ABSTRACTS 1 Poster Session III (Friday, November 7, 2014, 4:15 - 6:15 PM) new Fayum pangolins more closely resemble other Paleogene specimens rather than NEW BEST PRESERVED SPECIMENS OF DISCOSAURISCUS modern forms, suggests that modern pangolins must have arrived in Africa as a result of a PULCHERRIMUS (SEYMOURIAMORPHA, DISCOSAURISCIDAE) FROM THE subsequent, Neogene, invasion of the continent. LOWER PERMIAN SEDIMENTS OF BOSKOVICE BASIN (CZECH Although the L-41 pangolin is represented by only a distal phalanx, recovery of this REPUBLIC) element serves as an additional reference point for current arguments in Paleogene MIKUDÍKOVÁ, Marika, Comenius University, Bratislava, Slovakia; KLEMBARA, biogeography. Pangolins originated as part of a Laurasian fauna so their presence at L-41 Jozef, Comenius University, Bratislava, Slovakia is clear evidence for an immigrant taxon among endemic Fayum afrotheres. However, The Discosauriscus clade belongs to the well-studied reptiliomorph tetrapods. This among laurasiatheres, the phyletic place of pangolins is unresolved. Morphologically, genus is known from the Lower Permian of Central and Western Europe (Germany, pangolins have been considered the sister group to palaeanodonts, a predominantly North France, Czech Republic, Poland). Discosauriscus includes two species: D. austriacus American Paleocene–Eocene group of uncertain affinities. At the same time, molecular (known on the basis of several hundreds specimens) and D. pulcherrimus (known on the studies indicate that, among living forms, pangolins are most closely related to Carnivora. basis of several tens of poorly-preserved specimens). New findings of four three- It is possible that pangolins are related to palaeanodonts, and that this group represents dimensionally preserved specimens of D. pulcherrimus originate from the Lower the sister taxon to carnivores, although these relationships may be distant with pangolins, Permian of the Boskovice Basin (Czech Republic). Unfortunately, this species is very palaeanodonts and Carnivora all potentially rooted among the Leptictida. rare in this area (only five specimens were known prior to the new find). However, these four new specimens are the best-preserved individuals of this species yet recovered. For Technical Session X (Friday, November 7, 2014, 11:45 AM) this reason, we took this opportunity to study all cranial and postcranial elements and THE LAST MARCH OF THE PROBOSCIDEANS: CHANGES IN LANDSCAPE make new observations. For example, the ridges located in the central region of the USE AND MOBILITY PRECEDING THE PLEISTOCENE MEGAFAUNAL parasphenoid are described for the first time. A new reconstruction of the skull was EXTINCTION produced. MILLER, Joshua, University of Cincinnati, Cincinnati, OH, United States of America, Although, only nine specimens of D. pulcherrimus were found in Boskovice Basin, 45221; CROWLEY, Brooke, University of Cincinnai, Cincinnati, OH, United States of the individual variability of several characters can be clearly observed in these America specimens. These characters are as follows: 1) intensity of ornamentation of dermal skull During widespread extinction events, changing patterns of species landscape use bones, 2) degree of development of lateral line system, 3) development of nasolacrimal provide insight into the mechanisms and velocities of these biologically important duct, 4) arrangement of teeth on the pterygoids, 5) character of ornamentation of periods. The terminal Pleistocene offers a fossil record with high enough spatial and parasphenoid stem, and 6) shape of suborbital fenestra. The high individual variability is temporal resolutions to test for millennial-scale changes in species landscape use and also observable in D. austriacus. Thus, all these new morphological data, including mobility prior to, and synchronous with, extinction. Two sources of data from fossil information on individual variability, provide an oportunity for the revision of the remains are useful for establishing past mobility: (1) geographic locality data, and (2) diagnostic characters on the basis of which both species of Discosauriscus were defined. strontium isotope ratios (87Sr/86Sr). As rocks weather, Sr is released into overlying soils This project was partly supported by the Grant Agency of Comenius University, Grant nr. and surface waters, and subsequent incorporation of Sr into plants and animals occurs UK/342/2014. with little fractionation. Thus, organismal Sr ratios reflect the resources consumed during tissue formation. Matching organismal Sr ratios to local and regional geochemical signals Poster Session II (Thursday, November 6, 2014, 4:15 - 6:15 PM) historically required detailed sampling of local plants, animals, and water bodies, which DINOSAUR TECTONICS-WHEN BIOMECHANICS MEET STRUCTURAL complicated regional (or larger-scale) studies. Recently developed continental-scale Sr GEOLOGY models offer new opportunities to reconstruct movement patterns of highly mobile MILAN, Jesper, Østsjællands Museum, Faxe, Denmark; GRAVESEN, Ole, University of organisms. Here, using a combination of spatially explicit (GIS) analysis and continental- Copenhagen, Copenhagen, Denmark; LOOPE, David B., University of Nebraska, scale Sr models, we develop an analytical framework to test for changes in megafaunal Lincoln, NE, United States of America mobility prior to extinction. Our analyses focus on American mastodons (Mammut A theropod dinosaur trackway from finely laminated interdune deposits of the Middle americanum) and Columbian mammoths (Mammuthus columbi). We assessed mobility Jurassic eolian Entrada Sandstone shows a complex system of joints and faults created by using the difference between measured Sr ratios of the skeletal material and modeled the force exercised on the sediment during the time of contact between the trackmakers values for the specimen's recovery location. To estimate movement magnitude, we foot and the sediment. identified regions of North America that matched skeletal Sr ratios and calculated great Although in small scale, the structures of the faulted and folded sequence around the circle distances to those regions and least-cost paths using circuit theory. Results indicate track are comparable to crustal-scale tectonics associated with plate tectonics and mastodons and mammoths had significantly different geographic responses prior to foreland fold-thrust belts. extinction. Mammoths underwent a protracted and significant reduction in mobility By analyzing the structures in a structural geological perspective we are able to following the Last Glacial Maximum (p << 0.01) with a rapid and unprecedented recreate in detail the timing and weight distribution in the dinosaur”s foot during the increase in mobility within the millennium preceding their extinction. In contrast, different phases of the walk. mastodons exhibit more consistent mobility patterns across the Pleistocene, including Contrary to continent-continent collision, the observed dinosaur compression immediately prior to extinction. These results suggest that extinction pressures were structures are linked directly to an extensional field in the front of the track that balances geographically and/or taxonomically heterogeneous. Our analytical framework is the compression towards the back. The extension and the associated compression are conducive to a variety of geographic analyses of fossil data and future work will expand combined in a disk developed above an upward-concave, low-angle thrust established this study's taxonomic breadth. below the forepart of the dinosaur foot. In the touch-down to early kick-off phase, the downward and backward
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