DOCSLIB.ORG

Amurosaurus Riabinini from the Amur Region, Russia

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Amurosaurus Riabinini from the Amur Region, Russia Cranial Endocast of the Lambeosaurine Hadrosaurid Amurosaurus riabinini from the Amur Region, Russia Pascaline Lauters1,2*, Martine Vercauteren2, Yuri L. Bolotsky3, Pascal Godefroit1 1 Department of Palaeontology, Royal Belgian Institute of Natural Sciences, Bruxelles, Belgium, 2 Service d’Anthropologie et Ge´ne´tique Humaine, Universite´ Libre de Bruxelles, Bruxelles, Belgium, 3 Geological and Nature Exploration Institute, Far Eastern Branch of the Russian Academy of Sciences, Blagoveschensk, Russia Abstract Information on the structure of the brain of the lambeosaurine hadrosaurid dinosaur Amurosaurus riabinini, from the Late Maastrichtian of Blagoveschensk, Far Eastern Russia, is presented based on endocranial casts. The endocasts are compared with physical and digital endocasts of other dinosaurs. The olfactory tract was large. The cerebral hemispheres are enlarged and round, illustrating the important development of this part of the brain in hadrosaurids. The pituitary body is enlarged as well, perhaps prefiguring the large size attained by hadrosaurids. The EQ of Amurosaurus was similar to that of the lambeosaurine dinosaur Hypacrosaurus altispinus and was relatively larger than in most extant non-avian reptiles, including sauropod and ceratopsian dinosaurs. However, it was apparently relatively smaller than those of most theropod dinosaurs. The relatively large size of the cerebrum is consistent with the range and complexity of social behaviors inferred for lambeosaurine dinosaurs. Citation: Lauters P, Vercauteren M, Bolotsky YL, Godefroit P (2013) Cranial Endocast of the Lambeosaurine Hadrosaurid Amurosaurus riabinini from the Amur Region, Russia. PLoS ONE 8(11): e78899. doi:10.1371/journal.pone.0078899 Editor: Richard J. Butler, University of Birmingham, United Kingdom Received April 9, 2013; Accepted September 16, 2013; Published November 13, 2013 Copyright: ß 2013 Lauters et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This study was realized through the execution of S&T bilateral cooperation agreements on behalf of the Belgian State, Federal Scientific Policy. It constitutes part of a Ph.D. thesis by PL at the Universite´ Libre de Bruxelles, thanks to a grant from the Fonds pour la formation a` la Recherche dans l’Industrie et l’Agriculture. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: [email protected] Introduction morphology of the brain [13,14,15,16,17]. Subsequently, we compare the encephalization quotient and the cerebral volume of Since 1902, and the first discovery of dinosaur fossils in the Amurosaurus to those of other dinosaurs. Independently published Amur region (Far Eastern Russia), thousands of bones were data about the endocranial anatomy of this species based upon the collected from this area. Most of them belong to hadrosaurid taxa. same material [18] is also discussed, and interpretations contrasted Amurosaurus riabinini Bolotsky and Kurzanov, 1991 [1,2] and with those presented here. Finally, hypotheses about the behavior Kerberosaurus manakini Bolotsky and Godefroit, 2004 [3] were found of lambeosaurine hadrosaurid dinosaurs are proposed. in Blagoveschensk, whereas Olorotitan arharensis Godefroit, Bolotsky, and Alifanov, 2003 [4] was found in Kundur, both localities being Materials and Methods in the Amur Region of Far Eastern Russia. Charonosaurus jiayinensis Godefroit, Zan, and Jin, 2000 [5,6], Sahaliyania elunchunorum Institutional Abbreviations Godefroit, Shulin, Tinghai, and Lauters, 2008 [7] and Wulaga- AEHM, Amur Natural History Museum, of the Amur Complex saurus dongi Godefroit, Shulin, Tinghai, and Lauters, 2008 [7] were Integrated Research Institute of the Far Eastern Branch of the found in the adjacent region of China (Heilongjiang Province). Russian Academy of Sciences, Blagoveschensk, Russia (Amur Among this material, some braincases of Amurosaurus were KNII FEB RAS); IRSNB, Institut Royal des Sciences Naturelles found. The brain is a structure very sensitive to rapid decay after de Belgique, Brussels, Belgium. the death of the animal and is thus generally lost before any fossilization. Natural endocasts are rare [8,9], and until recently Specimens the endocranial cavity of fossil taxa was generally inaccessible for IRSNB R 279 (endocast of AEHM 1/232), IRSNB R 280 study without destructive preparation ([10]: p. 38). Recently, high- (endocast of AEHM 1/233), and IRSNB R 281 (endocast of resolution x-ray CT scan was often used to access the endocranial AEHM 1/90), and AEHM 1/240. cavity of fossil specimens. However, in some cases this method is impractical; the specimen may be too small or too large to be CT scanned, or researchers cannot access easily the machine or the Ethics Statement cost to use it is too high. It is also possible in some cases to make an This study is based on study of material held in the endocast without damaging the specimen, using materials such as collections of the Amur Natural History Museum. No permits silicone or latex rubber [11,12]. were required for the described study, which complied with all The purpose of this paper is to describe the endocast and the relevant regulations. cranial nerves of Amurosaurus riabinini, and is based on the assumption that the casts provide a good insight into the general PLOS ONE | www.plosone.org 1 November 2013 | Volume 8 | Issue 11 | e78899 Endocast of Amurosaurus riabinini Description ectotherms. Hopson [13] concluded that the EQs of dinosaurs The casts were obtained on the basis of a complete and are usually placed between those of modern ectotherms and undistorted braincase (AEHM 1/232) and partial braincases endotherms. Hurlburt [14] adapted Jerison’s ‘‘lower’’ vertebrate (AEHM 1/90 and AEHM 1/233) of Amurosaurus riabinini. AEHM equation for non-avian-reptiles and defined a Reptile Encephali- 0.553 1/232 and AEHM 1/90 were described in the revision of the zation Quotient (REQ). REQ = MBr/(0.0155*MBd ), where genus by Godefroit et al. [2]. The specimen AEHM 1/233 shows MBr is the mass of the brain (in grams), and MBd is the mass of the the prominent median process between the basipterygoid body (in grams). The mass of the brain is obtained by multiplying processes typical of Amurosaurus riabinini and is referred to this the volume of the brain by 1.036 g/ml [21]. taxon. The presence of valleculae was observed on an additional In extinct taxa, both the brain and body masses must be specimen (AEHM 1/240). The complete braincase (AEHM 1/ estimated, leading to many uncertainties in the calculation of the 232) was used to make the cast IRSNB R 279 and the description REQ. Given that no complete skeleton of Amurosaurus has been of the global features of the endocranial cavity. More details about discovered, it is difficult to estimate the mass of an adult individual, the cranial nerves could be observed on the casts of two partial because no braincase is directly associated to appendicular bones. braincases: IRSNB R 280 and IRSNB R 281. These specimens Because AEHM 1/232 clearly belongs to a large adult specimen, were collected during the 1980s field campaign from the Upper we selected the longest femur and humerus and measured their Cretaceous Udurchukan Formation (Maastrichtian, Late Creta- circumference in order to estimate the mass of a large adult ceous) by Yuri L. Bolotsky. The braincases are fused and from Amurosaurus. The specimens were selected according to their large, presumably adult, individuals. For a complete description of lambeosaurine characteristics [2] and for their size indicating that the braincase of this species, see Godefroit et al. [2]. For general they belonged to an adult individual [22]. In addition, the ratio of measurements of the braincase AEHM 1/232, see Table 1. The humerus/femur circumferences of the selected bones matches the specimens used here were also among those used by Saveliev et al. ratio obtained for articulated adult hadrosaurid skeletons [23,24]. [18] in their independent study of the endocranial anatomy of this REQ calculations for dinosaurs usually estimated the volume of species. However, this study is based on a different set of casts and the brain under the assumption that the brain occupied 50% of the new interpretations about the endocranial anatomy and possible endocranial volume [14,20,25]. According to Evans [17] and behavior of Amurosaurus are presented. Evans et al. [26], the extensive valleculae in hadrosaurids imply that the brain occupied a larger portion of the endocranial cavity The specimens were molded using the following technique. The than in other ornithischians and they calculated the REQ based complete braincase was prepared by covering the smallest on a brain size estimate of 60% endocast volume. Because foramina and fractures with modeling clay, the foramen magnum valleculae can also be observed in Amurosaurus specimens, we here was left free. A thin layer of Vaseline was sprayed into the follow the assumption of Evans et al. [26]. endocranial cavity to prevent excessive adherence of the silicone. Silicone was mixed with a catalyst and poured into the endocranial cavity to create the first endocranial silicone layer. This first layer Results was allowed to dry for at least 24 hours. Once dry, additional Systematic Paleontology silicone was poured at intervals to create a multi-layered cast. This DINOSAURIA Owen, 1842 [27] technique allows the strengthening of the endocranial cast and ORNITHISCHIA Seeley, 1887 [28] prevents its tearing. When the last layer of silicone was completely ORNITHOPODA Marsh, 1881 [29] dry, the endocranial cast was pulled out and the braincase was ANKYLOPOLLEXIA Sereno, 1986 [30] subsequently cleaned. HADROSAURIFORMES Sereno, 1986 [30] The volume of the endocast was measured by placing it, HADROSAUROIDEA Cope, 1869 [31] beforehand filled with tiny glass marbles, in water and measuring HADROSAURIDAE Cope, 1869 [31] water displacement.
Load more

Recommended publications
  • Beyond Endocasts: Using Predicted Brain-Structure Volumes of Extinct Birds to Assess Neuroanatomical and Behavioral Inferences
    diversity Article Beyond Endocasts: Using Predicted Brain-Structure Volumes of Extinct Birds to Assess Neuroanatomical and Behavioral Inferences 1, , 2 2 Catherine M. Early * y , Ryan C. Ridgely and Lawrence M. Witmer 1 Department of Biological Sciences, Ohio University, Athens, OH 45701, USA 2 Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA; [email protected] (R.C.R.); [email protected] (L.M.W.) * Correspondence: [email protected] Current Address: Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA. y Received: 1 November 2019; Accepted: 30 December 2019; Published: 17 January 2020 Abstract: The shape of the brain influences skull morphology in birds, and both traits are driven by phylogenetic and functional constraints. Studies on avian cranial and neuroanatomical evolution are strengthened by data on extinct birds, but complete, 3D-preserved vertebrate brains are not known from the fossil record, so brain endocasts often serve as proxies. Recent work on extant birds shows that the Wulst and optic lobe faithfully represent the size of their underlying brain structures, both of which are involved in avian visual pathways. The endocasts of seven extinct birds were generated from microCT scans of their skulls to add to an existing sample of endocasts of extant birds, and the surface areas of their Wulsts and optic lobes were measured. A phylogenetic prediction method based on Bayesian inference was used to calculate the volumes of the brain structures of these extinct birds based on the surface areas of their overlying endocast structures. This analysis resulted in hyperpallium volumes of five of these extinct birds and optic tectum volumes of all seven extinct birds.
    [Show full text]
  • 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.
    [Show full text]
  • Phylogeny and Biogeography of Iguanodontian Dinosaurs, with Implications from Ontogeny and an Examination of the Function of the Fused Carpal-Digit I Complex
    Phylogeny and Biogeography of Iguanodontian Dinosaurs, with Implications from Ontogeny and an Examination of the Function of the Fused Carpal-Digit I Complex By Karen E. Poole B.A. in Geology, May 2004, University of Pennsylvania M.A. in Earth and Planetary Sciences, August 2008, Washington University in St. Louis A Dissertation submitted to The Faculty of The Columbian College of Arts and Sciences of The George Washington University in partial fulfillment of the requirements for the degree of Doctor of Philosophy August 31, 2015 Dissertation Directed by Catherine Forster Professor of Biology The Columbian College of Arts and Sciences of The George Washington University certifies that Karen Poole has passed the Final Examination for the degree of Doctor of Philosophy as of August 10th, 2015. This is the final and approved form of the dissertation. Phylogeny and Biogeography of Iguanodontian Dinosaurs, with Implications from Ontogeny and an Examination of the Function of the Fused Carpal-Digit I Complex Karen E. Poole Dissertation Research Committee: Catherine A. Forster, Professor of Biology, Dissertation Director James M. Clark, Ronald Weintraub Professor of Biology, Committee Member R. Alexander Pyron, Robert F. Griggs Assistant Professor of Biology, Committee Member ii © Copyright 2015 by Karen Poole All rights reserved iii Dedication To Joseph Theis, for his unending support, and for always reminding me what matters most in life. To my parents, who have always encouraged me to pursue my dreams, even those they didn’t understand. iv Acknowledgements First, a heartfelt thank you is due to my advisor, Cathy Forster, for giving me free reign in this dissertation, but always providing valuable commentary on any piece of writing I sent her, no matter how messy.
    [Show full text]
  • EDITORIAL NOTE Collection of Paleontology Papers in Honor of The
    Anais da Academia Brasileira de Ciências (2019) 91(Suppl. 2): e20191434 (Annals of the Brazilian Academy of Sciences) Printed version ISSN 0001-3765 / Online version ISSN 1678-2690 http://dx.doi.org/10.1590/0001-3765201920191434 www.scielo.br/aabc | www.fb.com/aabcjournal EDITORIAL NOTE Collection of Paleontology Papers in honor of the Centenary of the Brazilian Academy of Sciences ALEXANDER W.A. KELLNER* and MARINA B. SOARES Laboratório de Sistemática e Tafonomia de Vertebrados Fósseis, Departamento de Geologia e Paleontologia do Museu Nacional/UFRJ, Quinta da Boa Vista, s/n, São Cristóvão, 20940-040 Rio de Janeiro, RJ, Brazil How to cite: KELLNER AWA AND SOARES MB. 2019. Collection of Paleontology Papers in honor of the Centenary of the Brazilian Academy of Sciences. An Acad Bras Cienc 91: e20191434. DOI 10.1590/0001-3765201920191434. The Brazilian Academy of Sciences is a non-profit organization (ABC 2019) that has completed one century of existence in 2016. A series of special publications was organized by the Annals of the Brazilian Academy of Sciences (AABC) in celebration of this important date (e.g., Kellner 2017, Crespilho 2018, Cavaleiro 2018). Here we have the pleasure to introduce the final of these volumes gathering 20 original contributions in paleontology, the science dedicated to the study of all evidences of life that have been preserved in layers of deep time. The topics presented here vary from the description of new species and specimens of flying reptiles, dinosaurs, and crocodylomorphs to studies on biogeography, osteohistology, and specific contributions provided by microfossils. Over 70 authors from different countries were involved in this volume, showing the increasing international integration of Brazilian paleontologists.
    [Show full text]
  • On the Paleontology of Animal Cognition: Using the Brain Dimensions of Modern Birds to Characterize Maniraptor Cognition
    12 Journal of Advanced Neuroscience Research, Special Issue, May-2017, 12-19 On the Paleontology of Animal Cognition: Using the Brain Dimensions of Modern Birds to Characterize Maniraptor Cognition Thomas M. Gaetano1, Margaret M. Yacobucci1 and Verner P. Bingman2,* 1Department of Geology, Bowling Green State University, Ohio, USA 2Department of Psychology and J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University, Ohio, USA Abstract: Drawing inferences on the characteristics, including behavior, of extinct species using comparisons with extant species has a long tradition in paleontology. Departing from the observation that extinct maniraptors possessed brains with a relatively long and narrow telencephalon, we used digital endocasts taken from 11 species of modern birds to determine if any of the sampled modern bird species displayed a similar telencephalic shape, and by inference, similar cognitive ability. The analysis revealed that the telencephalon of the double-crested cormorant (Phalacrocorax auritus) is extraordinarily narrow (large length-to-width ratio) and strikingly similar to Archaeopteryx and even some non-avian, maniraptoran dinosaurs. The relatively narrow brain in turn suggests a relatively small nidopallium subdivision of the telencephalon and associated impoverished general cognitive ability. This first-order brain-anatomical observation, together with the relatively ancient origins of a cormorant fossil record, suggest that cormorants could be used as a model for the general cognitive abilities of extinct maniraptors. Keywords: Brain endocasts, Comparative cognition, Double-crested cormorant, Hippocampus, Nidopallium, Paleoneurology. INTRODUCTION animal cognition, observations and experimental evidence from birds have also offered some extraordi- Considerations of the richness of animal cognitive nary examples of cognition [3].
    [Show full text]
  • Homo Erectus: a Bigger, Faster, Smarter, Longer Lasting Hominin Lineage
    Homo erectus: A Bigger, Faster, Smarter, Longer Lasting Hominin Lineage Charles J. Vella, PhD August, 2019 Acknowledgements Many drawings by Kathryn Cruz-Uribe in Human Career, by R. Klein Many graphics from multiple journal articles (i.e. Nature, Science, PNAS) Ray Troll • Hominin evolution from 3.0 to 1.5 Ma. (Species) • Currently known species temporal ranges for Pa, Paranthropus aethiopicus; Pb, P. boisei; Pr, P. robustus; A afr, Australopithecus africanus; Ag, A. garhi; As, A. sediba; H sp., early Homo >2.1 million years ago (Ma); 1470 group and 1813 group representing a new interpretation of the traditionally recognized H. habilis and H. rudolfensis; and He, H. erectus. He (D) indicates H. erectus from Dmanisi. • (Behavior) Icons indicate from the bottom the • first appearance of stone tools (the Oldowan technology) at ~2.6 Ma, • the dispersal of Homo to Eurasia at ~1.85 Ma, • and the appearance of the Acheulean technology at ~1.76 Ma. • The number of contemporaneous hominin taxa during this period reflects different Susan C. Antón, Richard Potts, Leslie C. Aiello, 2014 strategies of adaptation to habitat variability. Origins of Homo: Summary of shifts in Homo Early Homo appears in the record by 2.3 Ma. By 2.0 Ma at least two facial morphs of early Homo (1813 group and 1470 group) representing two different adaptations are present. And possibly 3 others as well (Ledi-Geraru, Uraha-501, KNM-ER 62000) The 1813 group survives until at least 1.44 Ma. Early Homo erectus represents a third more derived morph and one that is of slightly larger brain and body size but somewhat smaller tooth size.
    [Show full text]
  • 1000002291104.Pdf
    Quaternary International 211 (2010) 4–13 Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint Morphological and morphometric analysis of variation in the Zhoukoudian Homo erectus brain endocasts Xiujie Wu a,b,*, Lynne A. Schepartz c, Christopher J. Norton d a Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Xizhimenwaidajie 142, Box 643, Beijing 100044, China b State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 210008, China c Department of Anthropology, Florida State University, Tallahassee, FL 32306-7772, USA d Department of Anthropology, University of Hawaii at Manoa, Honolulu, HI 96822-2223, USA article info abstract Article history: The six Zhoukoudian (ZKD) Locality 1 Homo erectus specimens derive from stratigraphic levels 11–3 with Available online 19 July 2009 a geochronological span of approximately 0.3 Ma. This paper introduces the history of the ZKD endocasts and presents data on their morphological features and linear dimensions in order to evaluate variability in the sample over time and in the broader context of human brain evolution using a comparative sample of African and other Asian H. erectus fossils and modern Chinese males. The ZKD brains are very similar in their morphological characteristics, but there are also significant but subtle changes involving expansion of the frontal and occipital lobe breadths that correlate with the geochronology. The same is not true for general endocranial volume. The ZKD brains, together with other Asian and African H. erectus specimens, have low height dimensions and short parietal chords that distinguish them from the modern Chinese.
    [Show full text]
  • Ontogenetic and Adult Shape Variation in the Endocast of Tapirus: Implications for T
    East Tennessee State University Digital Commons @ East Tennessee State University Electronic Theses and Dissertations Student Works 5-2020 Ontogenetic and Adult Shape Variation in the Endocast of Tapirus: Implications for T. polkensis from the Gray Fossil Site Thomas M. Gaetano East Tennessee State University Follow this and additional works at: https://dc.etsu.edu/etd Part of the Other Neuroscience and Neurobiology Commons, Paleobiology Commons, Paleontology Commons, and the Zoology Commons Recommended Citation Gaetano, Thomas M., "Ontogenetic and Adult Shape Variation in the Endocast of Tapirus: Implications for T. polkensis from the Gray Fossil Site" (2020). Electronic Theses and Dissertations. Paper 3765. https://dc.etsu.edu/etd/3765 This Thesis - unrestricted is brought to you for free and open access by the Student Works at Digital Commons @ East Tennessee State University. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of Digital Commons @ East Tennessee State University. For more information, please contact [email protected]. Ontogenetic and Adult Shape Variation in the Endocast of Tapirus: Implications for T. polkensis from the Gray Fossil Site ________________________________ A thesis presented to the faculty of the Department of Geosciences East Tennessee State University In partial fulfillment of the requirements for the degree Masters of Science in Geosciences _________________________________ by Thomas M. Gaetano May 2020 _________________________________ Dr. Steven C. Wallace, Chair Dr. Christopher C. Widga Dr. Richard T. Carter Dr. Thomas C. Jones Keywords: Endocast, Paleoneurology, Tapir, Gray Fossil Site, Telencephalon, Sociality, Paleoecology, Sensory Ecology ABSTRACT Ontogenetic and Adult Shape Variation in the Endocast of Tapirus: Implications for T.
    [Show full text]
  • New Australopithecine Endocast, SK 1585, from Swartkrans, South Africa
    New Australopithecine Endocast, SK 1585, from Swartkrans, South Africa RALPH L. HOLLOWAY Deprrrtmrnt of Anthropology, Colttinbin University, New York, New York 10027 KEY WORDS Brain . Primates . Endocasts . Australopithecines. ABSTRACT The new SK 1585 endocast, found by Dr. Brain at Swartkrans, 1966, is that of a robust australopithecine, matching the endocast of the Olduvai Hominid 5 in volume, and being almost identical to it in morphology. Aside from Olduvai Hominid 5 it is the only robust australopithecine endocast com- plete enough to permit easy reconstruction, as only a small portion of the frontal lobe is missing. While the gyral and sulcal patterns are not clear, there are a number of features indicating that the brain is not that of a pongid, but that is has been reorganized to a hominid pattern, particularly the occipital, parietal, and temporal lobes. A new undistorted endocast, presuma- of visual inspection, after the surface of bly that of a robust australopithecine, the cast had been lightly rubbed with was discovered in January, 1966, by carbon shavings to enhance the surface Dr. C. K. Brain in the hillside dump rub- detail. Various combinations of lighting ble at Swartkrans (Brain, '70, '67). At the were employed to bring out features of kmd suggestion of Dr. Brain, I was in- cerebral morphology. vited to describe this endocast while visit- The volumetric determinations by water ing in Johannesburg during the early part displacement were carried out on plasti- of 1969. I am greatly indebted to Dr. cine reconstructed plaster copy, first Brain and Prof. P. V. Tobias for this checked for its accuracy against the orig- opportunity.
    [Show full text]
  • Relative Size of Brain and Cerebrum in Tyrannosaurus Rex: an Analysis Using Brain-Endocast Quantitative Relationships in Extant Alligators
    Sheridan College SOURCE: Sheridan Institutional Repository Faculty of Humanities & Social Sciences Publications and Scholarship (FHASS) Winter 2013 Relative size of brain and cerebrum in Tyrannosaurus rex: an analysis using brain-endocast quantitative relationships in extant alligators Grant R. Hurlburt Sheridan College, [email protected] Follow this and additional works at: https://source.sheridancollege.ca/fhass_publications SOURCE Citation Hurlburt, Grant R., "Relative size of brain and cerebrum in Tyrannosaurus rex: an analysis using brain- endocast quantitative relationships in extant alligators" (2013). Publications and Scholarship. 32. https://source.sheridancollege.ca/fhass_publications/32 This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License. This Book Chapter is brought to you for free and open access by the Faculty of Humanities & Social Sciences (FHASS) at SOURCE: Sheridan Institutional Repository. It has been accepted for inclusion in Publications and Scholarship by an authorized administrator of SOURCE: Sheridan Institutional Repository. For more information, please contact [email protected]. 6.1. Left lateral view of endo- cranial cast of wild Alligator mississippiensis. Skull length 34.3 cm, estimated body length, 2.6 m. Scale bar equals 1 cm. 134 ©2013 by Indiana University Press. All rights reserved. Relative Size of Brain and Cerebrum in Tyrannosaurid Dinosaurs: An Analysis 6 Using Brain-Endocast Quantitative Relationships in Extant Alligators Grant R. Hurlburt, Ryan C. Ridgely, and Lawrence M. Witmer Brain and cerebrum mass are estimated from endocasts of three tyran- Abstract nosaurid taxa (Tyrannosaurus rex, Gorgosaurus, and Nanotyrannus) using morphological and quantitative brain-endocast relations in a size series of sexually mature alligators (Alligator mississippiensis).
    [Show full text]
  • European Association of Vertebrate Palaeontologists
    10th Annual Meeting of the European Association of Vertebrate Palaeontologists Royo-Torres, R., Gascó, F. and Alcalá, L., coord. (2012). 10th Annual Meeting of the European Association of Vertebrate Palaeontologists. ¡Fundamental! 20: 1–290. EDITOR: © Fundación Conjunto Paleontológico de Teruel – Dinópolis COORDINATION: Rafael Royo-Torres, Francisco Gascó and Luis Alcalá. DISEÑO Y MAQUETA: © EKIX Soluciones Gráficas DL: TE–72–2012 ISBN–13: 978–84–938173–4–3 PROJECT: CGL 2009 06194-E/BTE Ministerio de Ciencia e Innovación Queda rigurosamente prohibida, sin la autorización escrita de los autores y del editor, bajo las sanciones establecidas en la ley, la reproducción total o parcial de esta obra por cualquier medio o procedimiento, comprendidos la reprografía y el tratamiento informático. Todos los derechos reservados. 2 • two posterior dorsal centra from Puerto de Tazones, described New ornithopod remains from the Upper Jurassic as Ankylopollexia indet. (Ruiz-Omeñaca et al., 2009), and of Asturias (North Spain) • a maxillary tooth from Aranzón, described as Dryomorpha indet. (Ruiz-Omeñaca et al., 2010). José Ignacio Ruiz-Omeñaca, Laura Piñuela In this paper we present six unpublished remains (Table I) and José Carlos García-Ramos and revise the assignation of the three cervical vertebrae to Museo del Jurásico de Asturias (MUJA), E-33328 Colunga, Spain. Camptosaurus. [email protected]; [email protected]; [email protected] Localities with ornithopod bony remains The ornithopod remains come from several localities in the Villaviciosa municipality (Table I).They are from west to east: Introduction Aranzón (Quintueles parish), Playa España-E (Villaverde parish), El Trébol-E and Careñes (Careñes parish), and Tazones W-1 and Ornithopod tracks are relatively frequent in the Late Jurassic Puerto de Tazones (Tazones parish).
    [Show full text]
  • New Evidence on Brain-Endocranial Cavity Relationships in Ornithischian
    New evidence on brain−endocranial cavity relationships in ornithischian dinosaurs DAVID C. EVANS Evans, D.C. 2005. New evidence on brain−endocranial cavity relationships in ornithischian dinosaurs. Acta Palaeonto− logica Polonica 50 (3): 617–622. Discussions of brain morphology and relative brain size in nonavian dinosaurs have been complicated by uncertainty in the extent to which the brain filled the endocranial cavity. Recently reported vascular imprints (valleculae) on the endocranial sur− faces of the braincase suggest that nonavian maniraptoriform theropods had brains that tightly fit the endocranium. Similar impressions of the intracranial vascular system are reported here in two ornithischian clades, Hadrosauridae and Pachy− cephalosauridae. These structures are more widespread in dinosaurs than previously thought, and suggest that the brain closely fit the endocranium in some regions of the forebrain through hindbrain in several distantly related dinosaur groups. Key words: Dinosauria, Hadrosauridae, Pachycephalosauridae, endocranial cavity, brain, Cretaceous. David C. Evans [[email protected]], University of Toronto, 3359 Mississauga Rd., Mississauga, ON, Canada, L5L 1C6. Introduction that complex endocranial vascular impressions also occur in hadrosaurid and pachycephalosaurid ornithischians, and that Traditionally nonavian dinosaurs have been regarded as “rep− the brain may have been closely associated with the endo− tilian” in that their brains were thought to have filled a rela− cranium in some regions of the forebrain and post−cerebrum in tively small portion of the endocranial cavity in contrast with these groups. the conditions in mammals and birds (Jerison 1969, 1973; Institutional abbreviations (all in Canada).—CMN, Cana− Hopson 1977, 1979; Rogers 1999; Larsson et al. 2000; Lars− dian Museum of Nature, Ottawa; ROM, Royal Ontario Mu− son 2001).
    [Show full text]