From the Upper Cretaceous of Mongolia
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Fused and Vaulted Nasals of Tyrannosaurid Dinosaurs: Implications for Cranial Strength and Feeding Mechanics
Fused and vaulted nasals of tyrannosaurid dinosaurs: Implications for cranial strength and feeding mechanics ERIC SNIVELY, DONALD M. HENDERSON, and DOUG S. PHILLIPS Snively, E., Henderson, D.M., and Phillips, D.S. 2006. Fused and vaulted nasals of tyrannosaurid dinosaurs: Implications for cranial strength and feeding mechanics. Acta Palaeontologica Polonica 51 (3): 435–454. Tyrannosaurid theropods display several unusual adaptations of the skulls and teeth. Their nasals are fused and vaulted, suggesting that these elements braced the cranium against high feeding forces. Exceptionally high strengths of maxillary teeth in Tyrannosaurus rex indicate that it could exert relatively greater feeding forces than other tyrannosaurids. Areas and second moments of area of the nasals, calculated from CT cross−sections, show higher nasal strengths for large tyrannosaurids than for Allosaurus fragilis. Cross−sectional geometry of theropod crania reveals high second moments of area in tyrannosaurids, with resulting high strengths in bending and torsion, when compared with the crania of similarly sized theropods. In tyrannosaurids trends of strength increase are positively allomeric and have similar allometric expo− nents, indicating correlated progression towards unusually high strengths of the feeding apparatus. Fused, arched nasals and broad crania of tyrannosaurids are consistent with deep bites that impacted bone and powerful lateral movements of the head for dismembering prey. Key words: Theropoda, Carnosauria, Tyrannosauridae, biomechanics, feeding mechanics, computer modeling, com− puted tomography. Eric Snively [[email protected]], Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada; Donald M. Henderson [[email protected]], Royal Tyrrell Museum of Palaeontology, Box 7500, Drumheller, Alberta T0J 0Y0, Canada; Doug S. -
The-Smartest-Dinosaur.Pdf
BY “DINO” DON LESSEM ILLUSTRATIONS BY JOHN BINDON a LERNER PUBLICATIONS COMPANY / MINNEAPOLIS To Emily Lessem, my favorite niece Text copyright © 2005 by Dino Don, Inc. Illustrations copyright © 2005 by John Bindon Photographs courtesy of: Dino Don, Inc., p. 12; Dr. Philip Currie, Royal Tyrrell Museum of Palaeontology, Drumheller, Alberta, Canada, p. 13; Photographed by Robert Fillion. Reproduced with permission of the Canadian Museum of Nature, Ottawa, Canada, p. 30; Animals, Animals © OSF/BARTLETT, D&J, p. 31. All rights reserved. International copyright secured. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means—electronic, mechanical, photocopying, recording, or otherwise—without the prior written permission of Lerner Publications Company, except for the inclusion of brief quotations in an acknowledged review. This book is available in two editions: Library binding by Lerner Publications Company, a division of Lerner Publishing Group Soft cover by First Avenue Editions, an imprint of Lerner Publishing Group 241 First Avenue North Minneapolis, MN 55401 U.S.A. Website address: www.lernerbooks.com Library of Congress Cataloging-in-Publication-Data Lessem, Don. The smartest dinosaurs / by Don Lessem ; illustrations by John Bindon. p. cm. — (Meet the dinosaurs) Includes index. eISBN: 0–8225–3285–9 1. Dinosaurs—Juvenile literature. I. Bindon, John, ill. II. Title. III. Series: Lessem, Don. Meet the dinosaurs. QE861.5.L477 2005 567.9—dc22 2004011152 Manufactured in the United States of America 1 2 3 4 5 6 – DP – 10 09 08 07 06 05 MEET THE SMARTEST DINOSAURS . 4 HOW SMART WERE DINOSAURS? . -
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’’. -
Brains and Intelligence
BRAINS AND INTELLIGENCE The EQ or Encephalization Quotient is a simple way of measuring an animal's intelligence. EQ is the ratio of the brain weight of the animal to the brain weight of a "typical" animal of the same body weight. Assuming that smarter animals have larger brains to body ratios than less intelligent ones, this helps determine the relative intelligence of extinct animals. In general, warm-blooded animals (like mammals) have a higher EQ than cold-blooded ones (like reptiles and fish). Birds and mammals have brains that are about 10 times bigger than those of bony fish, amphibians, and reptiles of the same body size. The Least Intelligent Dinosaurs: The primitive dinosaurs belonging to the group sauropodomorpha (which included Massospondylus, Riojasaurus, and others) were among the least intelligent of the dinosaurs, with an EQ of about 0.05 (Hopson, 1980). Smartest Dinosaurs: The Troodontids (like Troödon) were probably the smartest dinosaurs, followed by the dromaeosaurid dinosaurs (the "raptors," which included Dromeosaurus, Velociraptor, Deinonychus, and others) had the highest EQ among the dinosaurs, about 5.8 (Hopson, 1980). The Encephalization Quotient was developed by the psychologist Harry J. Jerison in the 1970's. J. A. Hopson (a paleontologist from the University of Chicago) did further development of the EQ concept using brain casts of many dinosaurs. Hopson found that theropods (especially Troodontids) had higher EQ's than plant-eating dinosaurs. The lowest EQ's belonged to sauropods, ankylosaurs, and stegosaurids. A SECOND BRAIN? It used to be thought that the large sauropods (like Brachiosaurus and Apatosaurus) and the ornithischian Stegosaurus had a second brain. -
Estimating Mass Properties of Dinosaurs Using Laser Imaging and 3D Computer Modelling
Estimating Mass Properties of Dinosaurs Using Laser Imaging and 3D Computer Modelling Karl T. Bates1*, Phillip L. Manning2,3, David Hodgetts3, William I. Sellers1 1 Adaptive Organismal Biology Research Group, Faculty of Life Sciences, University of Manchester, Jackson’s Mill, Manchester, United Kingdom, 2 The Manchester Museum, University of Manchester, Manchester, United Kingdom, 3 School of Earth, Atmospheric and Environmental Science, University of Manchester, Manchester, United Kingdom Abstract Body mass reconstructions of extinct vertebrates are most robust when complete to near-complete skeletons allow the reconstruction of either physical or digital models. Digital models are most efficient in terms of time and cost, and provide the facility to infinitely modify model properties non-destructively, such that sensitivity analyses can be conducted to quantify the effect of the many unknown parameters involved in reconstructions of extinct animals. In this study we use laser scanning (LiDAR) and computer modelling methods to create a range of 3D mass models of five specimens of non- avian dinosaur; two near-complete specimens of Tyrannosaurus rex, the most complete specimens of Acrocanthosaurus atokensis and Strutiomimum sedens, and a near-complete skeleton of a sub-adult Edmontosaurus annectens. LiDAR scanning allows a full mounted skeleton to be imaged resulting in a detailed 3D model in which each bone retains its spatial position and articulation. This provides a high resolution skeletal framework around which the body cavity and internal organs such as lungs and air sacs can be reconstructed. This has allowed calculation of body segment masses, centres of mass and moments or inertia for each animal. However, any soft tissue reconstruction of an extinct taxon inevitably represents a best estimate model with an unknown level of accuracy. -
A New Caenagnathid Dinosaur from the Upper Cretaceous Wangshi
www.nature.com/scientificreports OPEN A new caenagnathid dinosaur from the Upper Cretaceous Wangshi Group of Shandong, China, with Received: 12 October 2017 Accepted: 7 March 2018 comments on size variation among Published: xx xx xxxx oviraptorosaurs Yilun Yu1, Kebai Wang2, Shuqing Chen2, Corwin Sullivan3,4, Shuo Wang 5,6, Peiye Wang2 & Xing Xu7 The bone-beds of the Upper Cretaceous Wangshi Group in Zhucheng, Shandong, China are rich in fossil remains of the gigantic hadrosaurid Shantungosaurus. Here we report a new oviraptorosaur, Anomalipes zhaoi gen. et sp. nov., based on a recently collected specimen comprising a partial left hindlimb from the Kugou Locality in Zhucheng. This specimen’s systematic position was assessed by three numerical cladistic analyses based on recently published theropod phylogenetic datasets, with the inclusion of several new characters. Anomalipes zhaoi difers from other known caenagnathids in having a unique combination of features: femoral head anteroposteriorly narrow and with signifcant posterior orientation; accessory trochanter low and confuent with lesser trochanter; lateral ridge present on femoral lateral surface; weak fourth trochanter present; metatarsal III with triangular proximal articular surface, prominent anterior fange near proximal end, highly asymmetrical hemicondyles, and longitudinal groove on distal articular surface; and ungual of pedal digit II with lateral collateral groove deeper and more dorsally located than medial groove. The holotype of Anomalipes zhaoi is smaller than is typical for Caenagnathidae but larger than is typical for the other major oviraptorosaurian subclade, Oviraptoridae. Size comparisons among oviraptorisaurians show that the Caenagnathidae vary much more widely in size than the Oviraptoridae. Oviraptorosauria is a clade of maniraptoran theropod dinosaurs characterized by a short, high skull, long neck and short tail. -
Dating Dinosaurs
The PRINCETON FIELD GUIDE to DINOSAURS 2ND EDITION PRINCETON FIELD GUIDES Rooted in field experience and scientific study, Princeton’s guides to animals and plants are the authority for professional scientists and amateur naturalists alike. Princeton Field Guides present this information in a compact format carefully designed for easy use in the field. The guides illustrate every species in color and provide detailed information on identification, distribution, and biology. Albatrosses, Petrels, and Shearwaters of the World, by Derek Onley Birds of Southern Africa, Fourth Edition, by Ian Sinclair, Phil and Paul Scofield Hockey, Warwick Tarboton, and Peter Ryan Birds of Aruba, Curaçao, and Bonaire by Bart de Boer, Eric Birds of Thailand, by Craig Robson Newton, and Robin Restall Birds of the West Indies, by Herbert Raffaele, James Wiley, Birds of Australia, Eighth Edition, by Ken Simpson and Nicolas Orlando Garrido, Allan Keith, and Janis Raffaele Day Birds of Western Africa, by Nik Borrow and Ron Demey Birds of Borneo: Brunei, Sabah, Sarawak, and Kalimantan, by Carnivores of the World, by Luke Hunter Susan Myers Caterpillars of Eastern North America: A Guide to Identification Birds of Botswana, by Peter Hancock and Ingrid Weiersbye and Natural History, by David L. Wagner Birds of Central Asia, by Raffael Ayé, Manuel Schweizer, and Common Mosses of the Northeast and Appalachians, by Karl B. Tobias Roth McKnight, Joseph Rohrer, Kirsten McKnight Ward, and Birds of Chile, by Alvaro Jaramillo Warren Perdrizet Birds of the Dominican Republic and Haiti, by Steven Latta, Coral Reef Fishes, by Ewald Lieske and Robert Meyers Christopher Rimmer, Allan Keith, James Wiley, Herbert Dragonflies and Damselflies of the East, by Dennis Paulson Raffaele, Kent McFarland, and Eladio Fernandez Dragonflies and Damselflies of the West, by Dennis Paulson Birds of East Africa: Kenya, Tanzania, Uganda, Rwanda, and Mammals of Europe, by David W. -
'Big Al'? Quantifying the Effect of Soft
Palaeontologia Electronica http://palaeo-electronica.org HOW BIG WAS ‘BIG AL’? QUANTIFYING THE EFFECT OF SOFT TISSUE AND OSTEOLOGICAL UNKNOWNS ON MASS PREDICTIONS FOR ALLOSAURUS (DINOSAURIA:THEROPODA) Karl T. Bates, Peter L. Falkingham, Brent H. Breithaupt, David Hodgetts, William I. Sellers, and Phillip L. Manning ABSTRACT MOR693, nicknamed ‘Big Al,’ is the most complete skeleton of the non-avian theropod Allosaurus and therefore provides the best opportunity to investigate the mass properties of this important Jurassic theropod through accurate physical or digital volumetric models. In this study, laser scanning and computer modelling software have been used to construct volumetric models of MOR693. A long-range laser scanner has been used to digitize the mounted cast of MOR693, allowing the reconstruction of body volumes and respiratory structures around and within the three-dimensional (3D) skel- etal model. The digital medium offered the facility to modify model properties non- destructively in a detailed sensitivity analysis to quantify the effects of the many unknown parameters involved in such reconstructions. In addition to varying the vol- umes of body segments and respiratory structures, we also extend the sensitivity anal- ysis to include uncertainties regarding osteological articulations in non-avian dinosaurs, including effects of inter-vertebral spacing and the orientation or ‘flare’ of the rib cage in MOR693. Results suggest body mass and inertial values are extremely uncertain and show a wide range in plausible values, whilst the CM (centre of mass) position is well constrained immediately in front and below the hip joint in MOR693, consistent with similar reconstructions of non-avian theropods. Karl T. -
The Distinctive Theropod Assemblage of the Ellisdale Site of New Jersey and Its Implications for North American Dinosaur Ecology and Evolution During the Cretaceous
Journal of Paleontology, 92(6), 2018, p. 1115–1129 Copyright © 2018, 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. 0022-3360/15/0088-0906 doi: 10.1017/jpa.2018.42 The distinctive theropod assemblage of the Ellisdale site of New Jersey and its implications for North American dinosaur ecology and evolution during the Cretaceous Chase D. Brownstein Stamford Museum and Nature Center, Stamford CT 〈[email protected]〉 Abstract.—The Cretaceous landmass of Appalachia has preserved an understudied but nevertheless important record of dinosaurs that has recently come under some attention. In the past few years, the vertebrate faunas of several Appalachian sites have been described. One such locality, the Ellisdale site of the Cretaceous Marshalltown Forma- tion of New Jersey, has produced hundreds of remains assignable to dinosaurs, including those of hadrosauroids of several size classes, indeterminate ornithopods, indeterminate theropods, the teeth, cranial, and appendicular elements of dromaeosaurids, ornithomimosaurians, and tyrannosauroids, and an extensive microvertebrate assemblage. The theropod dinosaur record of the Ellisdale site is currently the most extensive and diverse known from the Campanian of Appalachia. Study of the Ellisdale theropod specimens suggests that at -
Immigrant Species, Or Native Species?
The Journal of Paleontological Sciences: JPS.C.2017.01 TESTING THE HYPOTHESES OF THE ORIGIN OF TYRANNOSAURUS REX: IMMIGRANT SPECIES, OR NATIVE SPECIES? __________________________________________________________________________________________________________________ Chan-gyu Yun Vertebrate Paleontological Institute of Incheon, Incheon 21974, Republic of Korea & Biological Sciences, Inha University, Incheon 22212, Republic of Korea [email protected] __________________________________________________________________________________________________________________ Abstract: It is an undoubtable fact that Tyrannosaurus rex is the most iconic dinosaur species of all time. However, it is currently debatable whether this species has a North American origin or Asian origin. In this paper, I test these two hypotheses based on current fossil records and former phylogenetic analyses. Phylogenetic and fossil evidence, such as derived tyrannosaurine fossils of Asia, suggests that the hypothesis of an Asian origin of Tyrannosaurus rex is the most plausible one, but this is yet to be certain due to the scarcity of fossil records. INTRODUCTION The most famous and iconic dinosaur of all time, Tyrannosaurus rex, is only known from upper Maastrichtian geological formations in Western North America (e.g. Carr and Williamson, 2004; Larson, 2008). However, older relatives of Tyrannosaurus rex (e.g. Daspletosaurus, Tarbosaurus) are known from both Asia and North America. This leads to an evolutionary question: is the origin of Tyrannosaurus rex from Asia, or North America? About six of the currently valid tyrannosaurine taxa were described in the twenty-first century (based on parsimony analysis of Brusatte and Carr, 2016), with new species which are being described (Sebastian Dalman, Pers. Comm., 2016; Thomas Carr, Pers. Comm., 2016). It can be said that "now" is the "golden age” for studying tyrannosaurine evolution. -
Index of Subjects
Cambridge University Press 978-1-108-47594-5 — Dinosaurs 4th Edition Index More Information INDEX OF SUBJECTS – – – A Zuul, 275 276 Barrett, Paul, 98, 335 336, 406, 446 447 Ankylosauridae Barrick, R, 383–384 acetabulum, 71, 487 characteristics of, 271–273 basal dinosauromorph, 101 acromial process, 271, 273, 487 cladogram of, 281 basal Iguanodontia, 337 actual diversity, 398 defined, 488 basal Ornithopoda, 336 adenosine diphosphate, see ADP evolution of, 279 Bates, K. T., 236, 360 adenosine triphosphate, see ATP ankylosaurids, 275–276 beak, 489 ADP (adenosine diphosphate), 390, 487 anpsids, 76 belief systems, 474, 489 advanced characters, 55, 487 antediluvian period, 422, 488 Bell, P. R., 162 aerobic metabolism, 391, 487 anterior position, 488 bennettitaleans, 403, 489 – age determination (dinosaur), 354 357 antorbital fenestra, 80, 488 benthic organisms, 464, 489 Age of Dinosaurs, 204, 404–405 Arbour, Victoria, 277 Benton, M. J., 2, 104, 144, 395, 402–403, akinetic movement, see kinetic movement Archibald, J. D., 467, 469 444–445, 477–478 Alexander, R. M., 361 Archosauria, 80, 88–90, 203, 488 Berman, D. S, 236–237 allometry, 351, 487 Archosauromorpha, 79–81, 488 Beurien, Karl, 435 altricial offspring, 230, 487 archosauromorphs, 401 bidirectional respiration, 350 Alvarez, Luis, 455 archosaurs, 203, 401 Big Al, 142 – Alvarez, Walter, 442, 454 455, 481 artifacts, 395 biogeography, 313, 489 Alvarezsauridae, 487 Asaro, Frank, 455 biomass, 415, 489 – alvarezsaurs, 168 169 ascending process of the astragalus, 488 biosphere, 2 alveolus/alveoli, -
Limb Design, Function and Running Performance in Ostrich-Mimics and Tyrannosaurs
GAIA Nº 15, LISBOA/LISBON, DEZEMBRO/DECEMBER 1998, pp. 257-270 (ISSN: 0871-5424) LIMB DESIGN, FUNCTION AND RUNNING PERFORMANCE IN OSTRICH-MIMICS AND TYRANNOSAURS Gregory S. PAUL 3109 N Calvert St. Side Apt., BALTIMORE MD 21218. USA ABSTRACT: Examination of the limb morphology of small ornithomimids and large tyranno- saurids shows that they remained remarkably constant in design regardless of size. The changes that were present were consistent with maintaining limb strength and function constant with size. It is concluded that ornithomimid and tyrannosaurid legs functioned in a similar manner, and always exhibit the features normally associated with a fast running gait. This is in contrast to modern animals, in which elephants as gigantic as large tyranno- saurids have limbs that are modified for a slow walking gait. INTRODUCTION to run observed in elephants. The hypothesis can be challenged if it can be shown that at least some ex- Because they had long, gracile, bird-like legs, it tinct giants retained the skeletal adaptations for run- has long been accepted that the smaller predatory ning observed in smaller species, and in their own dinosaurs were swift runners (O [& GREG- SBORN offspring. In turn, the hypothesis that giants can run ], 1916; COLBERT, 1961; RUSSELL, 1972; ORY fast if they retain limbs similar to smaller runners can C , 1978; THULBORN, 1982; PAUL, 1988; OOMBS be challenged if it is shown that the skeleton is too H , 1994). Much more controversial has been OLTZ vulnerable to structural failure. the locomotory abilities of their giant relatives, which have been restored as no faster than elephants BODY MASSES (LAMBE, 1917; HALSTEAD &HALSTEAD, 1981; THUL- BORN, 1982; BARSBOLD, 1983), able to run at only Sources for mass data for extinct and extant ani- modest speeds (COOMBS, 1978; MOLNAR &FAR- mals include PAUL (1988, 1997), NOWAK (1991) and LOW, 1990; HORNER &LESSEM, 1993; FARLOW, MATTHEWS (1994).