Dinosauropodes
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
New Heterodontosaurid Remains from the Cañadón Asfalto Formation: Cursoriality and the Functional Importance of the Pes in Small Heterodontosaurids
Journal of Paleontology, 90(3), 2016, p. 555–577 Copyright © 2016, The Paleontological Society 0022-3360/16/0088-0906 doi: 10.1017/jpa.2016.24 New heterodontosaurid remains from the Cañadón Asfalto Formation: cursoriality and the functional importance of the pes in small heterodontosaurids Marcos G. Becerra,1 Diego Pol,1 Oliver W.M. Rauhut,2 and Ignacio A. Cerda3 1CONICET- Museo Palaeontológico Egidio Feruglio, Fontana 140, Trelew, Chubut 9100, Argentina 〈[email protected]〉; 〈[email protected]〉 2SNSB, Bayerische Staatssammlung für Paläontologie und Geologie and Department of Earth and Environmental Sciences, LMU München, Richard-Wagner-Str. 10, Munich 80333, Germany 〈[email protected]〉 3CONICET- Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro, Museo Carlos Ameghino, Belgrano 1700, Paraje Pichi Ruca (predio Marabunta), Cipolletti, Río Negro, Argentina 〈[email protected]〉 Abstract.—New ornithischian remains reported here (MPEF-PV 3826) include two complete metatarsi with associated phalanges and caudal vertebrae, from the late Toarcian levels of the Cañadón Asfalto Formation. We conclude that these fossil remains represent a bipedal heterodontosaurid but lack diagnostic characters to identify them at the species level, although they probably represent remains of Manidens condorensis, known from the same locality. Histological features suggest a subadult ontogenetic stage for the individual. A cluster analysis based on pedal measurements identifies similarities of this specimen with heterodontosaurid taxa and the inclusion of the new material in a phylogenetic analysis with expanded character sampling on pedal remains confirms the described specimen as a heterodontosaurid. Finally, uncommon features of the digits (length proportions among nonungual phalanges of digit III, and claw features) are also quantitatively compared to several ornithischians, theropods, and birds, suggesting that this may represent a bipedal cursorial heterodontosaurid with gracile and grasping feet and long digits. -
A Phylogenetic Analysis of the Basal Ornithischia (Reptilia, Dinosauria)
A PHYLOGENETIC ANALYSIS OF THE BASAL ORNITHISCHIA (REPTILIA, DINOSAURIA) Marc Richard Spencer A Thesis Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements of the degree of MASTER OF SCIENCE December 2007 Committee: Margaret M. Yacobucci, Advisor Don C. Steinker Daniel M. Pavuk © 2007 Marc Richard Spencer All Rights Reserved iii ABSTRACT Margaret M. Yacobucci, Advisor The placement of Lesothosaurus diagnosticus and the Heterodontosauridae within the Ornithischia has been problematic. Historically, Lesothosaurus has been regarded as a basal ornithischian dinosaur, the sister taxon to the Genasauria. Recent phylogenetic analyses, however, have placed Lesothosaurus as a more derived ornithischian within the Genasauria. The Fabrosauridae, of which Lesothosaurus was considered a member, has never been phylogenetically corroborated and has been considered a paraphyletic assemblage. Prior to recent phylogenetic analyses, the problematic Heterodontosauridae was placed within the Ornithopoda as the sister taxon to the Euornithopoda. The heterodontosaurids have also been considered as the basal member of the Cerapoda (Ornithopoda + Marginocephalia), the sister taxon to the Marginocephalia, and as the sister taxon to the Genasauria. To reevaluate the placement of these taxa, along with other basal ornithischians and more derived subclades, a phylogenetic analysis of 19 taxonomic units, including two outgroup taxa, was performed. Analysis of 97 characters and their associated character states culled, modified, and/or rescored from published literature based on published descriptions, produced four most parsimonious trees. Consistency and retention indices were calculated and a bootstrap analysis was performed to determine the relative support for the resultant phylogeny. The Ornithischia was recovered with Pisanosaurus as its basalmost member. -
Examples from Dinosaur and Elephant Limb Imaging Studies John R
3 The Anatomical Foundation for Multidisciplinary Studies of Animal Limb Function: Examples from Dinosaur and Elephant Limb Imaging Studies John R. Hutchinson1, Charlotte Miller1, Guido Fritsch2, and Thomas Hildebrandt2 3.1 Introduction all we have to work with, at first. Yet that does not mean that behavior cannot be addressed by indi- What makes so many animals, living and extinct, rect scientifific means. so popular and distinct is anatomy; it is what leaps Here we use two intertwined case studies from out at a viewer fi rst whether they observe a muse- our research on animal limb biomechanics, one on um’s mounted Tyrannosaurus skeleton or an ele- extinct dinosaurs and another on extant elephants, phant placidly browsing on the savannah. Anatomy to illustrate how anatomical methods and evi- alone can make an animal fascinating – so many dence are used to solve basic questions. The dino- animals are so physically unlike human observers, saur study is used to show how biomechanical yet what do these anatomical differences mean for computer modeling can reveal how extinct animal the lives of animals? limbs functioned (with a substantial margin of The behavior of animals can be equally or more error that can be addressed explicitly in the stunning- how fast could a Tyrannosaurus move models). The elephant study is used to show (Coombs 1978; Alexander 1989; Paul 1998; Farlow how classical anatomical observation and three- et al. 2000; Hutchinson and Garcia 2002; Hutchin- dimensional (3D) imaging have powerful synergy son 2004a,b), or how does an elephant manage to for characterising extant animal morphology, momentarily support itself on one leg while without biomechanical modeling, but also as a first ‘running’ quickly (Gambaryan 1974; Alexander step toward such modeling. -
The First Possible Choristoderan Trackway from the Lower
www.nature.com/scientificreports OPEN The frst possible choristoderan trackway from the Lower Cretaceous Daegu Formation of South Korea and its implications on choristoderan locomotion Yuong‑Nam Lee1*, Dal‑Yong Kong2 & Seung‑Ho Jung2 Here we report a new quadrupedal trackway found in the Lower Cretaceous Daegu Formation (Albian) in the vicinity of Ulsan Metropolitan City, South Korea, in 2018. A total of nine manus‑pes imprints show a strong heteropodous quadrupedal trackway (length ratio is 1:3.36). Both manus and pes tracks are pentadactyl with claw marks. The manus prints rotate distinctly outward while the pes prints are nearly parallel to the direction of travel. The functional axis in manus and pes imprints suggests that the trackmaker moved along the medial side during the stroke progressions (entaxonic), indicating weight support on the inner side of the limbs. There is an indication of webbing between the pedal digits. These new tracks are assigned to Novapes ulsanensis, n. ichnogen., n. ichnosp., which are well‑matched not only with foot skeletons and body size of Monjurosuchus but also the fossil record of choristoderes in East Asia, thereby N. ulsanensis could be made by a monjurosuchid‑like choristoderan and represent the frst possible choristoderan trackway from Asia. N. ulsanensis also suggests that semi‑aquatic choristoderans were capable of walking semi‑erect when moving on the ground with a similar locomotion pattern to that of crocodilians on land. South Korea has become globally famous for various tetrapod footprints from Cretaceous strata1, among which some clades such as frogs2, birds3 and mammals4 have been proved for their existences only with ichnological evidence. -
A Case of a Tooth-Traced Tyrannosaurid Bone in the Lance Formation (Maastrichtian), Wyoming
PALAIOS, 2018, v. 33, 164–173 Research Article DOI: http://dx.doi.org/10.2110/palo.2017.076 TYRANNOSAUR CANNIBALISM: A CASE OF A TOOTH-TRACED TYRANNOSAURID BONE IN THE LANCE FORMATION (MAASTRICHTIAN), WYOMING MATTHEW A. MCLAIN,1 DAVID NELSEN,2 KEITH SNYDER,2 CHRISTOPHER T. GRIFFIN,3 BETHANIA SIVIERO,4 LEONARD R. BRAND,4 5 AND ARTHUR V. CHADWICK 1Department of Biological and Physical Sciences, The Master’s University, Santa Clarita, California 2Department of Biology, Southern Adventist University, Chattanooga, Tennessee, USA 3Department of Geosciences, Virginia Tech, Blacksburg, Virginia, USA 4Department of Earth and Biological Sciences, Loma Linda University, Loma Linda, California, USA 5Department of Biological Sciences, Southwestern Adventist University, Keene, Texas, USA email: [email protected] ABSTRACT: A recently discovered tyrannosaurid metatarsal IV (SWAU HRS13997) from the uppermost Cretaceous (Maastrichtian) Lance Formation is heavily marked with several long grooves on its cortical surface, concentrated on the bone’s distal end. At least 10 separate grooves of varying width are present, which we interpret to be scores made by theropod teeth. In addition, the tooth ichnospecies Knethichnus parallelum is present at the end of the distal-most groove. Knethichnus parallelum is caused by denticles of a serrated tooth dragging along the surface of the bone. Through comparing the groove widths in the Knethichnus parallelum to denticle widths on Lance Formation theropod teeth, we conclude that the bite was from a Tyrannosaurus rex. The shape, location, and orientation of the scores suggest that they are feeding traces. The osteohistology of SWAU HRS13997 suggests that it came from a young animal, based on evidence that it was still rapidly growing at time of death. -
Occurrence of Sauropod Dinosaur Tracks in the Upper Jurassic of Chile (Redescription of Iguanodonichnus Frenki)
Journal of South American Earth Sciences 20 (2005) 253–257 www.elsevier.com/locate/jsames Occurrence of sauropod dinosaur tracks in the Upper Jurassic of Chile (redescription of Iguanodonichnus frenki) Karen Moreno *, Michael J. Benton Earth Sciences Department, University of Bristol, Bristol BS8 1RJ, UK Received 7 July 2003; accepted 20 May 2005 Abstract New observations from the only studied Upper Jurassic dinosaur unit in South America, the Ban˜os del Flaco Formation, Chile, are presented herein. The original description of the ichnospecies Iguanodonichnus frenki contains several mistakes and information that needs updating. Therefore, we provide a redescription, including new data collected in the field, that supports I. frenki as a sauropod in origin on the basis of the following features: step angles average less than 1108; pes prints intersect the trackway midline; pes prints are longer than wide, with the long axis rotated outward; the claw impression of digit I is prominent and directed forward; and claws on digits II, III, and IV are strongly reduced. These morphological characteristics might give clues about the pes morphology of the South American Jurassic sauropods, whose foot bone remains are scarce. The presence of this sauropod ichnospecies in the Late Jurassic agrees with Early–Middle Jurassic faunal associations in South America. q 2005 Elsevier Ltd. All rights reserved. Keywords: Chile; Dinosaur footprints; Parabrontopodus; Sauropod; Upper Jurassic Resu´men En el presente trabajo se realizan nuevas observaciones acerca de las huellas de dinosaurios de la Formacio´n Ban˜os del Flaco, las cuales representan el u´nico registro conocido para Jura´sico Superior en Ame´rica del Sur. -
Chapter 9. Paleozoic Vertebrate Ichnology of Grand Canyon National Park
Chapter 9. Paleozoic Vertebrate Ichnology of Grand Canyon National Park By Lorenzo Marchetti1, Heitor Francischini2, Spencer G. Lucas3, Sebastian Voigt1, Adrian P. Hunt4, and Vincent L. Santucci5 1Urweltmuseum GEOSKOP / Burg Lichtenberg (Pfalz) Burgstraße 19 D-66871 Thallichtenberg, Germany 2Universidade Federal do Rio Grande do Sul (UFRGS) Laboratório de Paleontologia de Vertebrados and Programa de Pós-Graduação em Geociências, Instituto de Geociências Porto Alegre, Rio Grande do Sul, Brazil 3New Mexico Museum of Natural History and Science 1801 Mountain Road N.W. Albuquerque, New Mexico, 87104 4Flying Heritage and Combat Armor Museum 3407 109th St SW Everett, Washington 98204 5National Park Service Geologic Resources Division 1849 “C” Street, NW Washington, D.C. 20240 Introduction Vertebrate tracks are the only fossils of terrestrial vertebrates known from Paleozoic strata of Grand Canyon National Park (GRCA), therefore they are of great importance for the reconstruction of the extinct faunas of this area. For more than 100 years, the upper Paleozoic strata of the Grand Canyon yielded a noteworthy vertebrate track collection, in terms of abundance, completeness and quality of preservation. These are key requirements for a classification of tracks through ichnotaxonomy. This chapter proposes a complete ichnotaxonomic revision of the track collections from GRCA and is also based on a large amount of new material. These Paleozoic tracks were produced by different tetrapod groups, such as eureptiles, parareptiles, synapsids and anamniotes, and their size ranges from 0.5 to 20 cm (0.2 to 7.9 in) footprint length. As the result of the irreversibility of the evolutionary process, they provide useful information about faunal composition, faunal events, paleobiogeographic distribution and biostratigraphy. -
The Enamel Microstructure of Manidens Condorensis: New Hypotheses on the Ancestral State and Evolution of Enamel in Ornithischia
The enamel microstructure of Manidens condorensis: New hypotheses on the ancestral state and evolution of enamel in Ornithischia MARCOS G. BECERRA and DIEGO POL Becerra, M.G. and Pol, D. 2020. The enamel microstructure of Manidens condorensis: New hypotheses on the ancestral state and evolution of enamel in Ornithischia. Acta Palaeontologica Polonica 65 (1): 59–70. Previous studies on enamel microstructure in Ornithischia have focused on derived lineages of this clade based on species from the northern hemisphere. Here we describe the enamel microstructure of Manidens condorensis from the late Early Jurassic of Argentina that belongs to Heterodontosauridae (interpreted as the basal-most clade of Ornithischia). Enamel microstructure in the cheek teeth lacks a basal unit layer, presents incipient divergent crystallite as the dominant enamel type and parallel crystallite enamel type (with or without incrementing lines). Enamel of maxillary and dentary teeth differs from each other in enamel distribution (asymmetric vs. symmetric), structure (presence vs. absence of tubules, and less vs. more abundant parallel crystallite enamel with incrementing lines) and ordering (regular ordering of enamel types vs. in patches). The enamel microstructure of Manidens is the simplest of all known Ornithischia, and is more similar to that of the sauropodomorph Plateosaurus than to the one reported for the basal theropod Coelophysis. Similarities within Ornithischia are present with pachycephalosaurids and, to a lesser extent, with ankylosaurs. Phylogenetic -
Late Triassic Dinosaur Tracks Reinterpreted at Gettysburg National Military Park
LATE TRIASSIC DINOSAUR TRACKS REINTERPRETED AT GETTYSBURG NATIONAL MILITARY PARK BY VINCENT L. SANTUCCI AND ADRIAN P. H UNT fossil tracks has advanced signifi- ONG BEFORE THE FOOTSTEPS OF UNION cantly over the past two decades and confederate soldiers traversed and we are now able to offer a Lsouth-central Pennsylvania, early di- different interpretation of the nosaurs left their footprints in ancient mud. Gettysburg tracks. The fossil Fossilized tracks preserve evidence that di- tracks represent the ichnogenus nosaurs existed in the Gettysburg area over Atreipus which was first de- 200 million years ago during a time period scribed by Olsen and Baird in called the Triassic. The tracks also illustrate 1986. The tracks can be further another example of a NPS unit, primarily identified to the ichnospecies A. focused on cultural resources, that must face mil-fordensis. the challenges of managing and interpret- Atreipus milfordensis repre- ing paleontological resources. sents, as of yet, an undescribed The dinosaur tracks are preserved in dinosaur that exhibits a thero- blocks of mudstone that were quarried from podlike pes (foot) in combina- Figure 1. Fossil manus and pes tracks of Atreipus an area outside park boundaries. However, tion with a short-clawed and milfordensis from atop a stone bridge at Gettysburg the quarried blocks were transported to the functionally tridactyl (three- National Military Park, Pennsylvania. park and used in the construction of stone toed) manus (hand). The track bridges during the 1930s. In 1937, over 50 pattern indicates that this dinosaur habitu- Additionally, as with the Gettysburg fos- additional tracks were discovered in blocks ally used all four limbs in locomotion. -
A New Basal Ornithopod Dinosaur from the Lower Cretaceous of China
A new basal ornithopod dinosaur from the Lower Cretaceous of China Yuqing Yang1,2,3, Wenhao Wu4,5, Paul-Emile Dieudonné6 and Pascal Godefroit7 1 College of Resources and Civil Engineering, Northeastern University, Shenyang, Liaoning, China 2 College of Paleontology, Shenyang Normal University, Shenyang, Liaoning, China 3 Key Laboratory for Evolution of Past Life and Change of Environment, Province of Liaoning, Shenyang Normal University, Shenyang, Liaoning, China 4 Key Laboratory for Evolution of Past Life and Environment in Northeast Asia, Ministry of Education, Jilin University, Changchun, Jilin, China 5 Research Center of Paleontology and Stratigraphy, Jilin University, Changchun, Jilin, China 6 Instituto de Investigación en Paleobiología y Geología, CONICET, Universidad Nacional de Río Negro, Rio Negro, Argentina 7 Directorate ‘Earth and History of Life’, Royal Belgian Institute of Natural Sciences, Brussels, Belgium ABSTRACT A new basal ornithopod dinosaur, based on two nearly complete articulated skeletons, is reported from the Lujiatun Beds (Yixian Fm, Lower Cretaceous) of western Liaoning Province (China). Some of the diagnostic features of Changmiania liaoningensis nov. gen., nov. sp. are tentatively interpreted as adaptations to a fossorial behavior, including: fused premaxillae; nasal laterally expanded, overhanging the maxilla; shortened neck formed by only six cervical vertebrae; neural spines of the sacral vertebrae completely fused together, forming a craniocaudally-elongated continuous bar; fused scapulocoracoid with prominent -
Tetrapod Trackways from the Early Middle Devonian Period of Poland
Vol 463 | 7 January 2010 | doi:10.1038/nature08623 ARTICLES Tetrapod trackways from the early Middle Devonian period of Poland Grzegorz Niedz´wiedzki1, Piotr Szrek2,3, Katarzyna Narkiewicz3, Marek Narkiewicz3 & Per E. Ahlberg4 The fossil record of the earliest tetrapods (vertebrates with limbs rather than paired fins) consists of body fossils and trackways. The earliest body fossils of tetrapods date to the Late Devonian period (late Frasnian stage) and are preceded by transitional elpistostegids such as Panderichthys and Tiktaalik that still have paired fins. Claims of tetrapod trackways predating these body fossils have remained controversial with regard to both age and the identity of the track makers. Here we present well-preserved and securely dated tetrapod tracks from Polish marine tidal flat sediments of early Middle Devonian (Eifelian stage) age that are approximately 18 million years older than the earliest tetrapod body fossils and 10 million years earlier than the oldest elpistostegids. They force a radical reassessment of the timing, ecology and environmental setting of the fish–tetrapod transition, as well as the completeness of the body fossil record. The last quarter-century has seen a dramatic expansion in the known Valentia Island, Ireland36, have been dated radiometrically to 385 million body fossil record of Devonian tetrapods, the earliest known limbed years ago. At the time of publication this was taken to imply an Eifelian vertebrates1–21. Equally importantly, the discovery of articulated (early Middle Devonian) age39, which clashed with the occurrence of specimens of elpistostegids, the animals that fall immediately below the Late Devonian index fossil (for Laurussia) Bothriolepis in the same them in the tetrapod stem group, has greatly enhanced our under- strata. -
Moenkopi Posters
Triassic Pre-Dinosaurian Communities, National Park’s Land, Utah: The Oldest Megatracksite in North America MICKELSON, Debra L., University of Colorado at Boulder, Boulder CO 80309, KVALE, Erik P., Indiana University, Bloomington, IN; 47405 Location WORTHINGTON, David, Capitol Reef National Park, Torrey UT 84775; Inclined Heterolithic Structures SANTUCCI, Vincent L., Fossil Butte National Monument, Kemmerer, WY 83101; HENDERSON, Norm R., Glen Canyon National Recreation Area, Page, AZ 86040 Abstract Recent exploration in the Capitol Reef National Park (CRNP) and Glen Canyon National Recreation Area (GCNRA) has revealed new sites of terrestrial and subaqueous vertebrate traces and is the oldest and most laterally extensive megatracksite surface documented in Track-Bearing Surfaces North America. Two different vertebrate track types (Chirotherium) Hintze, 1988 and (Rhynchosauroides) and rare fish fin drag marks (Undichna) have been identified in the Torrey Member of the Moenkopi Formation (Early Triassic). Multiple vertebrate ichnostratigraphic units are distinguished in the Torrey Member based on the strati- Geology graphic occurrence of track sites within CRNP and GCNRA Park's B The Torrey Member of the Moenkopi Formation has been the boundaries. Tracks are preserved as convex hyporelief sandstone E D subject of investigation for almost 50 years (Mckee, 1954; Smith et al, 1963; casts filling impressions in the underlying mudstones. Exposed Blakey, 1973 and 1977; Stokes 1980). However, these studies were more A broad based regional studies, and only recently has the Torrey Member been traces occur on the undersides of resistant sandstone ledges where the C studied in stratigraphic detail with emphasis on the extensive tetrapod track- mudstone has eroded away.