Knowledge Organiser for Year 3 & 4 Topic: Footprints from the Past

Total Page:16

File Type:pdf, Size:1020Kb

Knowledge Organiser for Year 3 & 4 Topic: Footprints from the Past Knowledge Organiser for Year 3 & 4 Topic: Footprints From The Past Key questions: How do we use historic items to understand the past? E.g. fossils. How have the continents changed from 250 million years ago to the modern day? How did the dinosaurs become extinct? Can you describe the differences between carnivores, herbivores and omnivores? Can you describe the differences between the terms ‘predator’ and ‘prey’? Key facts and figures Dinosaurs roamed the planet for about 165 million years, during a time in the Earth’s history called the Mesozoic Era. The Mezosoic Era comprised the Triassic, Jurassic and Cretaceous periods. To qualify for being a dinosaur you have to be, firstly, a reptile. Secondly, you have to be land-living, either walking on two or four legs. Thirdly, you have to have lived only within the Mesozoic era. At the beginning of the Triassic period, the world would have looked very different, as one half of the planet was a giant, joined-together super-continent called Pangaea. The other half was an immense ocean. By the end of the Cretaceous period, the super-continent was breaking apart, creating the outlines of continents we now know, and new shallow seas. We also now know that the continents are always in a process of very slow movement called Plate Tectonics or Continental Drift. 251 – 200 million years ago: The Triassic was marked by dry conditions with a distinct rainy season and large red deserts. It was here that the first small dinosaurs appeared. Examples of dinosaurs present: Plateosaurus, Gojirasaurus, Coelophysis and Herrerasaurus. 200 – 146 million years ago: The Jurassic was much wetter and lusher, causing a great expansion of dinosaur evolution, with increasingly bigger species of herbivorous dinosaur feeding on conifer and cycad forests. Examples of dinosaurs present: Stegosaurus, Allosaurus, Brachiosaurus and Ceratosaurus. 146 – 65 million years ago: The climate during the Cretaceous was affected by the breaking up of Pangaea, forming continents called Laurasia and Gondwana. Most of modern Europe was like the Caribbean, with shallow tropical sea and islands. New, different types of dinosaur had evolved, as well as birds and small mammals, turtles and snakes, etc. There were new types of flowering and fruiting plants Examples of dinosaurs present: Triceratops, Tyrannosaurus Rex, Centrosaurus and Ankylosaurus. About 65.5 million years ago, nearly all large vertebrates and many tropical invertebrates became extinct in what was clearly a geological, climatic and biological event with worldwide consequences. The most popular theory for this catastrophe was a very large asteroid colliding with Earth in what is now Mexico, on the Yucatan Peninsula. Did you know…? A palaeontologist is a person who studies the fossils of dinosaurs The word ‘dinosaur’ comes from the Greek words ‘deinos’ and ‘sauros’ meaning ‘terrible reptile’, a name coined by Richard Owen in 1841 There are roughly 700 known species of extinct dinosaurs Dinosaurs existed for approximately 200 million years Key vocabulary or people Mezosoic Era Pangea Triassic Period Continental drift Jurassic Period Yucatan Peninsula Cretaceous Period Richard Owen .
Recommended publications
  • KENNETH CARPENTER, Ph.D. Director and Curator Of
    KENNETH CARPENTER, Ph.D. Director and Curator of Paleontology Prehistoric Museum Utah State University - College of Eastern Utah 155 East Main Street Price, Utah 84501 Education May, 1996. Ph.D., Geology University of Colorado, Boulder, CO. Dissertation “Sharon Springs Member, Pierre Shale (Lower Campanian) depositional environment and origin of it' s Vertebrate fauna, with a review of North American plesiosaurs” 251 p. May, 1980. B.S. in Geology, University of Colorado, Boulder, CO. Aug-Dec. 1977 Apprenticeship, Smithsonian Inst., Washington DC Professional Museum Experience 1975 – 1980: University of Colorado Museum, Boulder, CO. 1983 – 1984: Mississippi Museum of Natural History, Jackson, MS. 1984 – 1986: Academy of Natural Sciences of Philadelphia, Philadelphia. 1986: Carnegie Museum of Natural History, Pittsburgh, PA. 1986: Oklahoma Museum of Natural History, Norman, OK. 1987 – 1989: Museum of the Rockies, Bozeman, MT. 1989 – 1996: Chief Preparator, Denver Museum of Nature and Science, Denver, CO. 1996 – 2010: Chief Preparator, and Curator of Vertebrate Paleontology, Denver Museum of Nature and Science, Denver, CO. 2006 – 2007; 2008-2009: Acting Department Head, Chief Preparator, and Curator of Vertebrate Paleontology, Denver Museum of Nature and Science, Denver, CO. 2010 – present: Director, Prehistoric Museum, Price, UT 2010 – present: Associate Vice Chancellor, Utah State University Professional Services: 1991 – 1998: Science Advisor, Garden Park Paleontological Society 1994: Senior Organizer, Symposium "The Upper Jurassic Morrison Formation: An Interdisciplinary Study" 1996: Scientific Consultant Walking With Dinosaurs , BBC, England 2000: Scientific Consultant Ballad of Big Al , BBC, England 2000 – 2003: Associate Editor, Journal of Vertebrate Paleontology 2001 – 2003: Associate Editor, Earth Sciences History journal 2003 – present: Scientific Advisor, HAN Project 21 Dinosaur Expos, Tokyo, Japan.
    [Show full text]
  • The Origin and Early Evolution of Dinosaurs
    Biol. Rev. (2010), 85, pp. 55–110. 55 doi:10.1111/j.1469-185X.2009.00094.x The origin and early evolution of dinosaurs Max C. Langer1∗,MartinD.Ezcurra2, Jonathas S. Bittencourt1 and Fernando E. Novas2,3 1Departamento de Biologia, FFCLRP, Universidade de S˜ao Paulo; Av. Bandeirantes 3900, Ribeir˜ao Preto-SP, Brazil 2Laboratorio de Anatomia Comparada y Evoluci´on de los Vertebrados, Museo Argentino de Ciencias Naturales ‘‘Bernardino Rivadavia’’, Avda. Angel Gallardo 470, Cdad. de Buenos Aires, Argentina 3CONICET (Consejo Nacional de Investigaciones Cient´ıficas y T´ecnicas); Avda. Rivadavia 1917 - Cdad. de Buenos Aires, Argentina (Received 28 November 2008; revised 09 July 2009; accepted 14 July 2009) ABSTRACT The oldest unequivocal records of Dinosauria were unearthed from Late Triassic rocks (approximately 230 Ma) accumulated over extensional rift basins in southwestern Pangea. The better known of these are Herrerasaurus ischigualastensis, Pisanosaurus mertii, Eoraptor lunensis,andPanphagia protos from the Ischigualasto Formation, Argentina, and Staurikosaurus pricei and Saturnalia tupiniquim from the Santa Maria Formation, Brazil. No uncontroversial dinosaur body fossils are known from older strata, but the Middle Triassic origin of the lineage may be inferred from both the footprint record and its sister-group relation to Ladinian basal dinosauromorphs. These include the typical Marasuchus lilloensis, more basal forms such as Lagerpeton and Dromomeron, as well as silesaurids: a possibly monophyletic group composed of Mid-Late Triassic forms that may represent immediate sister taxa to dinosaurs. The first phylogenetic definition to fit the current understanding of Dinosauria as a node-based taxon solely composed of mutually exclusive Saurischia and Ornithischia was given as ‘‘all descendants of the most recent common ancestor of birds and Triceratops’’.
    [Show full text]
  • A Juvenile Coelophysoid Skull from the Early Jurassic of Zimbabwe, and the Synonymy of Coelophysis and Syntarsus
    A juvenile coelophysoid skull from the Early Jurassic of Zimbabwe, and the synonymy of Coelophysis and Syntarsus Anthea Bristowe* & Michael A. Raath Bernard Price Institute for Palaeontological Research, School of Geosciences, University of the Witwatersrand, Private Bag 3, WITS, 2050 South Africa Received 23 September 2004. Accepted 5 December 2004 Several authors have drawn attention to the close similarities between the neotheropod dinosaurs Coelophysis and Syntarsus. Recon- struction and analysis of a skull from a juvenile specimen of Syntarsus (collected from the Forest Sandstone Formation of Zimbabwe) show that cranial characters previously used to distinguish these taxa and justify their generic separation (namely the presence of a ‘nasal fenestra’ in Syntarsus and the length of its antorbital fenestra), were based on erroneous reconstructions of disassociated cranial elements. On the basis of this reinterpretation we conclude that Syntarsus is a junior synonym of Coelophysis. Variations are noted in three cranial characters – the length of the maxillary tooth row, the width of the base of the lachrymal and the shape of the antorbital maxillary fossa – that taken together with the chronological and geographical separation of the two taxa justify separation at species level. Keywords: Dinosaurs, Neotheropoda, Coelophysoid, taxonomy, Triassic, Jurassic. INTRODUCTION Following the work of Gauthier (1986), these taxa were Ever since the theropod Syntarsus rhodesiensis was first suggested to belong to a monophyletic clade known as described (Raath 1969), a succession of authors have Ceratosauria. However, more recent works by a number commented on the close morphological similarity be- of authors (Sereno 1997, 1999; Holtz 2000; Wilson et al. tween it and Coelophysis bauri (Raath 1969, 1977; Paul 1988, 2003; Rauhut 2003) have re-evaluated theropod interrela- 1993; Colbert 1989; Rowe 1989; Tykoski 1998; Downs tionships.
    [Show full text]
  • Subject Index
    Cambridge University Press 0521811724 - The Evolution and Extinction of the Dinosaurs, Second Edition David E. Fastovsky and David B. Weishampel Index More information Subject index Bold type indicates figures. Absolute age 23–5 Arctic dinosaurs 372–373, 373 Actinopterygii 67 Asteroid impact 425, 426–32 Aguja Formation (Upper Cretaceous, USA) 401 see also Cretaceous–Tertiary boundary; Alxa Desert (China) 297 Iridium; Chicxulub Amarga Canyon (Argentina) 262 Affects of 432–4 American Museum of Natural History (USA) Indicators of 426, 427–9, 428, 429, 430, 431 18n, 19, 253, 259, 292 Atlas Mountains (Morocco) 263 Amnion 77 Auca Mahuevo (Upper Cretaceous, Argentina) Amniota 245, 246 Diagnostic characters 77, 78 Aves, see Theropoda Major groups 78 Azendoh (Morocco) 261 Amphibia 77, 77n, 393 Amur River (Sino-Russian border) 217 Baharije Oasis (Egypt) 291, 292 Anapsida 78, 79–80 Barun Goyot Formation (Upper Cretaceous, Anhui Province (China) 162 Mongolia) 401 Ankylosauria Bernissart (Belgium) 212, 213 Age 133, 396, 397 Biological classification 68 Armament 133, 137, 138, 139 Biostratigraphy 22, 27–8 Behavior 134–7, 138–9 Birds, see Theropoda Clades of 133, 139–42 Body plans 65 Cladogram of, see Cladograms Bone histology 362–7, 363 Derived characters of 140, 139–41, 142 British Museum (Natural History) 234, 258, 336 Distribution 134, 135 Bug Creek (USA) 441 Evolution of 139 Burgess Shale (Middle Cambrian, Canada) 64 Fermentation in 136, 137 Burial 6, 7, 8, 9, 10 History of discovery 142–5 Inferred intelligence 361 Canadian Dinosaur Rush 182, 183,
    [Show full text]
  • A New Theropod Dinosaur from the Early Jurassic of South Africa and Its Implications for the Early Evolution of Theropods
    A new theropod dinosaur from the Early Jurassic of South Africa and its implications for the early evolution of theropods Adam M. Yates Bernard Price Institute for Palaeontological Research, School of Geosciences, University of the Witwatersrand, Private Bag 3, WITS 2050, Johannesburg, South Africa E-mail: [email protected] Received 27 June 2005. Accepted 21 September 2005 A new theropod, Dracovenator regenti, from the upper Elliot Formation is described, based upon a fragmentary skull. It can be diagnosed on the basis of a bilobed fossa on the lateral surface of the premaxilla that is connected to the alveolar margin by a narrow channel, the presence of a deep, oblique, lateral notch on the articular and hypertrophied dorsal processes on the articular. Other aspects of its morphology display a mosaic of coelophysoid and advanced theropod characteristics. A cladistic analysis of basal Theropoda, including the new taxon finds that the new taxon is closely related to Dilophosaurus wetherilli and Zupaysaurus rougieri although the clade formed by these three taxa is not robustly supported. It also finds that Coelophysoidea sensu lato is paraphyletic with respect to Ceratosauria + Tetanurae but that this topology is not a significantly better explanation of the data than an inclusive, monophyletic Coelophysoidea. Keywords: Theropoda, Coelophysoidea, Dracovenator, upper Elliot Formation, South Africa. INTRODUCTION 2004). It is now the majority view amongst theropod Prior to Gauthier’s classic (1986) monograph, our under- systematists that Ceratosauria contains Ceratosaurus spp. standing of the interrelationships of theropod dinosaurs and Abelisauroidea and that this clade is more closely could be described as murky at best.
    [Show full text]
  • Large Neotheropods from the Upper Triassic of North America and the Early Evolution of Large Theropod Body Sizes
    Journal of Paleontology, 93(5), 2019, p. 1010–1030 Copyright © 2019, The Paleontological Society. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/ licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. 0022-3360/19/1937-2337 doi: 10.1017/jpa.2019.13 Large neotheropods from the Upper Triassic of North America and the early evolution of large theropod body sizes Christopher T. Griffin Department of Geosciences, Virginia Tech, Blacksburg, Virginia 24061, USA <[email protected]> Abstract.—Large body sizes among nonavian theropod dinosaurs is a major feature in the evolution of this clade, with theropods reaching greater sizes than any other terrestrial carnivores. However, the early evolution of large body sizes among theropods is obscured by an incomplete fossil record, with the largest Triassic theropods represented by only a few individuals of uncertain ontogenetic stage. Here I describe two neotheropod specimens from the Upper Triassic Bull Canyon Formation of New Mexico and place them in a broader comparative context of early theropod anatomy. These specimens possess morphologies indicative of ontogenetic immaturity (e.g., absence of femoral bone scars, lack of co-ossification between the astragalus and calcaneum), and phylogenetic analyses recover these specimens as early-diverging neotheropods in a polytomy with other early neotheropods at the base of the clade. Ancestral state recon- struction for body size suggests that the ancestral theropod condition was small (∼240 mm femur length), but the ances- tral neotheropod was larger (∼300–340 mm femur length), with coelophysoids experiencing secondary body size reduction, although this is highly dependent on the phylogenetic position of a few key taxa.
    [Show full text]
  • From the Upper Triassic (Revueltian) Snyder Quarry
    Zeigler, K.E., Heckert, A.B., and Lucas, S.G., eds., 2003, Paleontology and Geology of the Snyder Quarry, New Mexico Museum of Natural History and Science Bulletin No. 24. 127 COELOPHYSIDS (DINOSAURIA:THEROPODA) FROM THE UPPER TRIASSIC (REVUELTIAN) SNYDER QUARRY ANDREW B. HECKERT, KATE E. ZEIGLER, SPENCER G. LUCAS and LARRY F. RINEHART New Mexico Museum of Natural History and Science, 1801 Mountain Road NW, Albuquerque, NM 87104-1375 Abstract—The Snyder quarry preserves one of the richest assemblages of Norian theropods in the world, and the second-most productive theropod locality in the Chinle Group. At least four coelophysid theropods are preserved at the Snyder quarry, based on tibiae. Most elements of these theropods are represented, including an incomplete skull and lower jaws, cervical, dorsal, sacral, and caudal vertebrae, a scapulocoracoid, ilia, ischia, femora, tibiae, a fibula, astragalocalcanea, and diverse carpals and tarsals. These specimens demonstrate that the Snyder quarry theropods pertain to the Revueltian theropod Eucoelophysis, only known from the type local- ity at Orphan Mesa 10 km to the east and Baldwin’s original collection described by Cope in 1881. Theropod dinosaurs at the Snyder quarry are the most abundant terrestrial predators, and outnumber rauisuchians and sphenosuchians. These theropods are, with the “Padian theropod” from the same unit in the Petrified Forest National Park and Procompsognathus from the Stubensandstein in Germany, part of an apparently Pangean radiation of coelophysid theropods during Revueltian (early-mid Norian) time. Keywords: Norian, theropod, ceratosaur, Eucoelophysis INTRODUCTION The Snyder quarry (NMMNH locality 3845) in north-central New Mexico is an extraordinarily rich bonebed that preserves an archosaur- dominated vertebrate assemblage that appears to represent the after- math of a catastrophic event (Heckert et al., 2000a; Zeigler, 2003).
    [Show full text]
  • Dinosaurs Take Flight
    SPECIAL ISSUE: DINOSAURS TAKE FLIGHT Terrible Lizards: A New Family Portrait nside the U.S. and Russian Space Programs - , _aunches September 17 October 1 2005 US Destinations ' Russian Destinations Rose Center for Earth and Sp Baykonur Cosmodrome *" New York City Kazakhstan ' Goddard Space Center , Mission Control Greenbelt, MD ;. Moscow, Russia Smithsonian Institution, Yuri Gagarin # | Cosmonaut National Air & Space Musetil Training Center Washington D.C. - 1, (GCTC) Moscow Kennedy Space Cente*"^* 'ptional Cosmonaut Training Cape Canaveral, FL 1 Star City Johnson Space Cent Houston, TX An around-the-world, red-carpet seminar examining humankind's ongoing efforts in planetary science and space travel i^ERiCAN Museum S Natural History ^ • Discovery Tours Central Park yVest^t 79th Street, New York, New York 1 0024-5 I 92 ::^|Ei|462.-8687 or 2 1 2-769-5toB^??^P?TI 2-769-5755 E-mail: [email protected] www.discoverytours.org MAY 2005 VOLUME 114 NUMBER SPECIAL ISSUE: DINOSAURS TAKE FLIGHT FEATURES 40 ALL IN THE FAMILY A dadogmm shows how dinosaurs are related to one another—and where the birds fit in. 42 BIRD'S-EYE VIEW 34 THE VARIETIES OF TYRANNOSAURS Because modern dinosaurs are flying all around us, examining Knowledge about the most 48 BUTTING HEADS them closely can ofler new fearsome dinosaurs and their relatives Thefour greatest controversies insights into the lives is finally measuring up in dinosaur science of theirfossilized ancestors. to the animals' fame. J. DAVID ARCHIBALD MATTHEW T. CARRANO MARK A. NORELL AND XU XING SANKAR CHATTERJEE LUIS M. CHIAPPE AND PATRICK M. O'CONNOR ANDREW A.
    [Show full text]
  • Paläontologische Gesellschaft Programme, Abstracts, and Field Guides
    TERRA NOSTRA Schriften der GeoUnion Alfred-Wegener-Stiftung – 2012/3 Centenary Meeting of the Paläontologische Gesellschaft Programme, Abstracts, and Field Guides 24.09. – 29.09.2012 Museum für Naturkunde Berlin Edited by Florian Witzmann & Martin Aberhan Cover-Abstract.indd 1 24.08.12 15:52 IMPRINT TERRA NOSTRA – Schriften der GeoUnion Alfred-Wegener-Stiftung Publisher Verlag GeoUnion Alfred-Wegener-Stiftung Arno-Holz-Str. 14, 12165 Berlin, Germany Tel.: +49 (0)30 7900660, Fax: +49 (0)30 79006612 Email: [email protected] Editorial office Dr. Christof Ellger Schriftleitung GeoUnion Alfred-Wegener-Stiftung Arno-Holz-Str. 14, 12165 Berlin, Germany Tel.: +49 (0)30 79006622, Fax: +49 (0)30 79006612 Email: [email protected] Vol. 2012/3 Centenary Meeting of the Paläontologische Gesellschaft. Heft 2012/3 Programme, Abstracts, and Field Guides Jubiläumstagung der Paläontologischen Gesellschaft. Programm, Kurzfassungen und Exkursionsführer Editors Florian Witzmann & Martin Aberhan Herausgeber Editorial staff Faysal Bibi, George A. Darwin, Franziska Heuer, Wolfgang Kiessling, Redaktion Dieter Korn, Sarah Löwe, Uta Merkel, Thomas Schmid-Dankward Printed by Druckerei Conrad GmbH, Oranienburger Str. 172, 13437 Berlin Druck Copyright and responsibility for the scientific content of the contributions lie with the authors. Copyright und Verantwortung für den wissenschaftlichen Inhalt der Beiträge liegen bei den Autoren. ISSN 0946-8978 GeoUnion Alfred-Wegener-Stiftung – Berlin, September 2012 Centenary Meeting of the Paläontologische Gesellschaft Programme, Abstracts, and Field Guides 24.09. – 29.09.2012 Museum für Naturkunde Berlin Edited by Florian Witzmann & Martin Aberhan Organisers: Martin Aberhan, Jörg Fröbisch Oliver Hampe, Wolfgang Kiessling Johannes Müller, Christian Neumann Manja Voss, Florian Witzmann Table of Contents Welcome ...........................................................
    [Show full text]
  • Marshandrowe2020.Pdf
    Journal of Paleontology, Volume 94, Memoir 78, 2020, p. 1–103 Copyright © 2020, The Paleontological Society 0022-3360/20/1937-2337 doi: 10.1017/jpa.2020.14 A comprehensive anatomical and phylogenetic evaluation of Dilophosaurus wetherilli (Dinosauria, Theropoda) with descriptions of new specimens from the Kayenta Formation of northern Arizona Adam D. Marsh1,2 and Timothy B. Rowe1 1Jackson School of Geosciences, the University of Texas at Austin, 2305 Speedway Stop C1160, Austin, Texas 78712, USA <[email protected]><[email protected]> 2Division of Resource Management, Petrified Forest National Park, 1 Park Road #2217, Petrified Forest, Arizona 86028, USA Abstract.—Dilophosaurus wetherilli was the largest animal known to have lived on land in North America during the Early Jurassic. Despite its charismatic presence in pop culture and dinosaurian phylogenetic analyses, major aspects of the skeletal anatomy, taxonomy, ontogeny, and evolutionary relationships of this dinosaur remain unknown. Skeletons of this species were collected from the middle and lower part of the Kayenta Formation in the Navajo Nation in northern Arizona. Redescription of the holotype, referred, and previously undescribed specimens of Dilophosaurus wetherilli supports the existence of a single species of crested, large-bodied theropod in the Kayenta Formation. The parasagittal nasolacrimal crests are uniquely constructed by a small ridge on the nasal process of the premaxilla, dorsoventrally expanded nasal, and tall lacrimal that includes a posterior process behind the eye. The cervical vertebrae exhibit serial variation within the posterior centrodiapophyseal lamina, which bifurcates and reunites down the neck. Iterative specimen-based phylogenetic analyses result in each of the additional specimens recovered as the sister taxon to the holotype.
    [Show full text]
  • Triassic Vertebrate Paleontology in New Mexico
    Archived version from NCDOCKS Institutional Repository http://libres.uncg.edu/ir/asu/ TRIASSIC VERTEBRATE PALEONTOLOGY IN NEW MEXICO By: Andrew B. Heckert and Spencer G. Lucas Abstract The Triassic vertebrate paleontological record of New Mexico includes important assemblages of tetrapod fossils from both the Middle Triassic Moenkopi Formation and the Upper Triassic Chinle Group. The Anton Chico Member of the Moenkopi Formation preserves primarily temnospondyl amphibian body fossils, but the record of reptiles comprises both sparse body fossil assemblages and more abundant track assemblages, mostly of chirotheriid reptiles. A bonebed accumulation of temnospondyls assigned to Eocyclotosaurus appetolatus is particularly notable. The Upper Triassic Chinle Group in New Mexico preserves an array of vertebrate faunal assemblages that represent the entirety of Chinle “time,” and includes numerous bonebeds of Revueltian age as well as the best records of Apachean vertebrates in the American West. These include the characteristic assemblages of the Revueltian and Apachean land- vertebrate faunachrons. Lucas, S. G. and Sullivan, R. M., eds. , 2015, Fossil Vertebrates in New Mexico. New Mexico Museum of Natural History and Science Bulletin 68. New Mexico Museum of Natural History and Science Lucas, S. G. and Sullivan, R. M., eds. , 2015, Fossil Vertebrates in New Mexico. New Mexico Museum of Natural History and Science Bulletin 68. 77 TRIASSIC VERTEBRATE PALEONTOLOGY IN NEW MEXICO ANDREW B. HECKERT1 and SPENCER G. LUCAS2 1Department of Geology, ASU Box 32067, Appalachian State University, Boone, NC 28608-2067 -email: [email protected]; 2New Mexico Museum of Natural History & Science, 1801 Mountain Road NW, Albuquerque, NM 87104 Abstract—The Triassic vertebrate paleontological record of New Mexico includes important assemblages of tetrapod fossils from both the Middle Triassic Moenkopi Formation and the Upper Triassic Chinle Group.
    [Show full text]
  • New Information on Segisaurus Halli, a Small Theropod Dinosaur from the Early Jurassic of Arizona
    Journal of Vertebrate Paleontology 25(4):835–849, December 2005 © 2005 by the Society of Vertebrate Paleontology NEW INFORMATION ON SEGISAURUS HALLI, A SMALL THEROPOD DINOSAUR FROM THE EARLY JURASSIC OF ARIZONA MATTHEW T. CARRANO1*, JOHN R. HUTCHINSON2, and SCOTT D. SAMPSON3 1Department of Paleobiology, Smithsonian Institution, P.O. Box 37012, MRC 121, Washington, DC 20013-7012, U.S.A., [email protected]; 2Structure and Motion Laboratory, The Royal Veterinary College, University of London, North Mymms, Hatfield, Hertfordshire, AL9 7TA, United Kingdom, [email protected]; 3Utah Museum of Natural History and Department of Geology and Geophysics, 1390 East Presidents Circle, University of Utah, Salt Lake City, UT 84112-0050, U.S.A., [email protected] ABSTRACT—Here we redescribe the holotype and only specimen of Segisaurus halli, a small Early Jurassic dinosaur and the only theropod known from the Navajo Sandstone. Our study highlights several important and newly recognized features that clarify the relationships of this taxon. Segisaurus is clearly a primitive theropod, although it does possess a tetanuran-like elongate scapular blade. Nonetheless, it appears to be a coelophysoid, based on the presence of a pubic fenestra, a long and ventrally curved pubis, and some pelvic (and possibly tarsal) fusion. Segisaurus does possess a furcula, as has now been observed in other coelophysoids, thus strengthening the early appearance of this ‘avian’ feature. The absence of an external fundamental system in bone histology sections and the presence of sutural contact lines in the caudal vertebrae, scapulocoracoid, and (possibly) between the pubis and ischium support the inference that this specimen is a subadult, neither a true juvenile nor at full skeletal maturity.
    [Show full text]