An Ontogenetic Series and Population Histology of The
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On the Stratigraphic Range of the Dicynodont Taxon Emydops (Therapsida: Anomodontia) in the Karoo Basin, South Africa
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Wits Institutional Repository on DSPACE On the stratigraphic range of the dicynodont taxon Emydops (Therapsida: Anomodontia) in the Karoo Basin, South Africa Kenneth D. Angielczyk1*, Jörg Fröbisch2 & Roger M.H. Smith3 1Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, BS8 1RJ, United Kingdom 2Department of Biology, University of Toronto at Mississauga, 3359 Mississauga Rd., Mississauga, ON, L5L 1C6, Canada 3Divison of Earth Sciences, South African Museum, P.O. Box 61, Cape Town, 8000 South Africa Received 19 May 2005. Accepted 8 June 2006 The dicynodont specimen SAM-PK-708 has been referred to the genera Pristerodon and Emydops by various authors, and was used to argue that the first appearance of Emydops was in the Tapinocephalus Assemblage Zone in the Karoo Basin of South Africa. However, the specimen never has been described in detail, and most discussions of its taxonomic affinities were based on limited data. Here we redescribe the specimen and compare it to several small dicynodont taxa from the Tapinocephalus and Pristerognathus assemblage zones. Although the specimen is poorly preserved, it possesses a unique combination of features that allows it to be assigned confidently to Emydops. The locality data associated with SAM-PK-708 are vague, but they allow the provenance of the specimen to be narrowed down to a relatively limited area southwest of the town of Beaufort West. Strata from the upper Tapinocephalus Assemblage Zone and the Pristerognathus Assemblage Zone crop out in this area, but we cannot state with certainty from which of these biostratigraphic divisions the specimen was collected. -
A Neoceratopsian Dinosaur from the Early Cretaceous of Mongolia And
ARTICLE https://doi.org/10.1038/s42003-020-01222-7 OPEN A neoceratopsian dinosaur from the early Cretaceous of Mongolia and the early evolution of ceratopsia ✉ Congyu Yu 1 , Albert Prieto-Marquez2, Tsogtbaatar Chinzorig 3,4, Zorigt Badamkhatan4,5 & Mark Norell1 1234567890():,; Ceratopsia is a diverse dinosaur clade from the Middle Jurassic to Late Cretaceous with early diversification in East Asia. However, the phylogeny of basal ceratopsians remains unclear. Here we report a new basal neoceratopsian dinosaur Beg tse based on a partial skull from Baruunbayan, Ömnögovi aimag, Mongolia. Beg is diagnosed by a unique combination of primitive and derived characters including a primitively deep premaxilla with four pre- maxillary teeth, a trapezoidal antorbital fossa with a poorly delineated anterior margin, very short dentary with an expanded and shallow groove on lateral surface, the derived presence of a robust jugal having a foramen on its anteromedial surface, and five equally spaced tubercles on the lateral ridge of the surangular. This is to our knowledge the earliest known occurrence of basal neoceratopsian in Mongolia, where this group was previously only known from Late Cretaceous strata. Phylogenetic analysis indicates that it is sister to all other neoceratopsian dinosaurs. 1 Division of Vertebrate Paleontology, American Museum of Natural History, New York 10024, USA. 2 Institut Català de Paleontologia Miquel Crusafont, ICTA-ICP, Edifici Z, c/de les Columnes s/n Campus de la Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès Sabadell, Barcelona, Spain. 3 Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA. 4 Institute of Paleontology, Mongolian Academy of Sciences, ✉ Ulaanbaatar 15160, Mongolia. -
At Carowinds
at Carowinds EDUCATOR’S GUIDE CLASSROOM LESSON PLANS & FIELD TRIP ACTIVITIES Table of Contents at Carowinds Introduction The Field Trip ................................... 2 The Educator’s Guide ....................... 3 Field Trip Activity .................................. 4 Lesson Plans Lesson 1: Form and Function ........... 6 Lesson 2: Dinosaur Detectives ....... 10 Lesson 3: Mesozoic Math .............. 14 Lesson 4: Fossil Stories.................. 22 Games & Puzzles Crossword Puzzles ......................... 29 Logic Puzzles ................................. 32 Word Searches ............................... 37 Answer Keys ...................................... 39 Additional Resources © 2012 Dinosaurs Unearthed Recommended Reading ................. 44 All rights reserved. Except for educational fair use, no portion of this guide may be reproduced, stored in a retrieval system, or transmitted in any form or by any Dinosaur Data ................................ 45 means—electronic, mechanical, photocopy, recording, or any other without Discovering Dinosaurs .................... 52 explicit prior permission from Dinosaurs Unearthed. Multiple copies may only be made by or for the teacher for class use. Glossary .............................................. 54 Content co-created by TurnKey Education, Inc. and Dinosaurs Unearthed, 2012 Standards www.turnkeyeducation.net www.dinosaursunearthed.com Curriculum Standards .................... 59 Introduction The Field Trip From the time of the first exhibition unveiled in 1854 at the Crystal -
Feeding Height Stratification Among the Herbivorous
Mallon et al. BMC Ecology 2013, 13:14 http://www.biomedcentral.com/1472-6785/13/14 RESEARCH ARTICLE Open Access Feeding height stratification among the herbivorous dinosaurs from the Dinosaur Park Formation (upper Campanian) of Alberta, Canada Jordan C Mallon1,5*, David C Evans2, Michael J Ryan3 and Jason S Anderson4 Abstract Background: Herbivore coexistence on the Late Cretaceous island continent of Laramidia has been a topic of great interest, stemming from the paradoxically high diversity and biomass of these animals in relation to the relatively small landmass available to them. Various hypotheses have been advanced to account for these facts, of which niche partitioning is among the most frequently invoked. However, despite its wide acceptance, this hypothesis has not been rigorously tested. This study uses the fossil assemblage from the Dinosaur Park Formation of Alberta as a model to investigate whether niche partitioning facilitated herbivorous dinosaur coexistence on Laramidia. Specifically, the question of feeding height stratification is examined in light of the role it plays in facilitating modern ungulate coexistence. Results: Most herbivorous dinosaur species from the Dinosaur Park Formation were restricted to feeding no higher than approximately 1 m above the ground. There is minimal evidence for feeding height partitioning at this level, with ceratopsids capable of feeding slightly higher than ankylosaurs, but the ecological significance of this is ambiguous. Hadrosaurids were uniquely capable of feeding up to 2 m quadrupedally, or up to 5 m bipedally. There is no evidence for either feeding height stratification within any of these clades, or for change in these ecological relationships through the approximately 1.5 Ma record of the Dinosaur Park Formation. -
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. -
A Revision of the Ceratopsia Or Horned Dinosaurs
MEMOIRS OF THE PEABODY MUSEUM OF NATURAL HISTORY VOLUME III, 1 A.R1 A REVISION orf tneth< CERATOPSIA OR HORNED DINOSAURS BY RICHARD SWANN LULL STERLING PROFESSOR OF PALEONTOLOGY AND DIRECTOR OF PEABODY MUSEUM, YALE UNIVERSITY LVXET NEW HAVEN, CONN. *933 MEMOIRS OF THE PEABODY MUSEUM OF NATURAL HISTORY YALE UNIVERSITY Volume I. Odontornithes: A Monograph on the Extinct Toothed Birds of North America. By Othniel Charles Marsh. Pp. i-ix, 1-201, pis. 1-34, text figs. 1-40. 1880. To be obtained from the Peabody Museum. Price $3. Volume II. Part 1. Brachiospongidae : A Memoir on a Group of Silurian Sponges. By Charles Emerson Beecher. Pp. 1-28, pis. 1-6, text figs. 1-4. 1889. To be obtained from the Peabody Museum. Price $1. Volume III. Part 1. American Mesozoic Mammalia. By George Gaylord Simp- son. Pp. i-xvi, 1-171, pis. 1-32, text figs. 1-62. 1929. To be obtained from the Yale University Press, New Haven, Conn. Price $5. Part 2. A Remarkable Ground Sloth. By Richard Swann Lull. Pp. i-x, 1-20, pis. 1-9, text figs. 1-3. 1929. To be obtained from the Yale University Press, New Haven, Conn. Price $1. Part 3. A Revision of the Ceratopsia or Horned Dinosaurs. By Richard Swann Lull. Pp. i-xii, 1-175, pis. I-XVII, text figs. 1-42. 1933. To be obtained from the Peabody Museum. Price $5 (bound in cloth), $4 (bound in paper). Part 4. The Merycoidodontidae, an Extinct Group of Ruminant Mammals. By Malcolm Rutherford Thorpe. In preparation. -
Histology and Ontogeny of Pachyrhinosaurus Nasal Bosses By
Histology and Ontogeny of Pachyrhinosaurus Nasal Bosses by Elizabeth Kruk A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Systematics and Evolution Department of Biological Sciences University of Alberta © Elizabeth Kruk, 2015 Abstract Pachyrhinosaurus is a peculiar ceratopsian known only from Upper Cretaceous strata of Alberta and the North Slope of Alaska. The genus consists of three described species Pachyrhinosaurus canadensis, Pachyrhinosaurus lakustai, and Pachyrhinosaurus perotorum that are distinguishable by cranial characteristics, including parietal horn shape and orientation, absence/presence of a rostral comb, median parietal bar horns, and profile of the nasal boss. A fourth species of Pachyrhinosaurus is described herein and placed into its phylogenetic context within Centrosaurinae. This new species forms a polytomy at the crown with Pachyrhinosaurus canadensis and Pachyrhinosaurus perotorum, with Pachyrhinosaurus lakustai falling basal to that polytomy. The diagnostic features of this new species are an apomorphic, laterally curved Process 3 horns and a thick longitudinal ridge separating the supraorbital bosses. Another focus is investigating the ontogeny of Pachyrhinosaurus nasal bosses in a histological context. Previously, little work has been done on cranial histology in ceratopsians, focusing instead on potential integumentary structures, the parietals of Triceratops, and how surface texture relates to underlying histological structures. An ontogenetic series is established for the nasal bosses of Pachyrhinosaurus at both relative (subadult versus adult) and fine scale (Stages 1-5). It was demonstrated that histology alone can indicate relative ontogenetic level, but not stages of a finer scale. Through Pachyrhinosaurus ontogeny the nasal boss undergoes increased vascularity and secondary remodeling with a reduction in osteocyte lacunar density. -
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. -
The Role of Fossils in Interpreting the Development of the Karoo Basin
Palaeon!. afr., 33,41-54 (1997) THE ROLE OF FOSSILS IN INTERPRETING THE DEVELOPMENT OF THE KAROO BASIN by P. J. Hancox· & B. S. Rubidge2 IGeology Department, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa 2Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa ABSTRACT The Permo-Carboniferous to Jurassic aged rocks oft1:J.e main Karoo Basin ofSouth Africa are world renowned for the wealth of synapsid reptile and early dinosaur fossils, which have allowed a ten-fold biostratigraphic subdivision ofthe Karoo Supergroup to be erected. The role offossils in interpreting the development of the Karoo Basin is not, however, restricted to biostratigraphic studies. Recent integrated sedimentological and palaeontological studies have helped in more precisely defming a number of problematical formational contacts within the Karoo Supergroup, as well as enhancing palaeoenvironmental reconstructions, and basin development models. KEYWORDS: Karoo Basin, Biostratigraphy, Palaeoenvironment, Basin Development. INTRODUCTION Invertebrate remains are important as indicators of The main Karoo Basin of South Africa preserves a facies genesis, including water temperature and salinity, retro-arc foreland basin fill (Cole 1992) deposited in as age indicators, and for their biostratigraphic potential. front of the actively rising Cape Fold Belt (CFB) in Fossil fish are relatively rare in the Karoo Supergroup, southwestern Gondwana. It is the deepest and but where present are useful indicators of gross stratigraphically most complete of several depositories palaeoenvironments (e.g. Keyser 1966) and also have of Permo-Carboniferous to Jurassic age in southern biostratigraphic potential (Jubb 1973; Bender et al. Africa and reflects changing depositional environments 1991). -
Physical and Environmental Drivers of Paleozoic Tetrapod Dispersal Across Pangaea
ARTICLE https://doi.org/10.1038/s41467-018-07623-x OPEN Physical and environmental drivers of Paleozoic tetrapod dispersal across Pangaea Neil Brocklehurst1,2, Emma M. Dunne3, Daniel D. Cashmore3 &Jӧrg Frӧbisch2,4 The Carboniferous and Permian were crucial intervals in the establishment of terrestrial ecosystems, which occurred alongside substantial environmental and climate changes throughout the globe, as well as the final assembly of the supercontinent of Pangaea. The fl 1234567890():,; in uence of these changes on tetrapod biogeography is highly contentious, with some authors suggesting a cosmopolitan fauna resulting from a lack of barriers, and some iden- tifying provincialism. Here we carry out a detailed historical biogeographic analysis of late Paleozoic tetrapods to study the patterns of dispersal and vicariance. A likelihood-based approach to infer ancestral areas is combined with stochastic mapping to assess rates of vicariance and dispersal. Both the late Carboniferous and the end-Guadalupian are char- acterised by a decrease in dispersal and a vicariance peak in amniotes and amphibians. The first of these shifts is attributed to orogenic activity, the second to increasing climate heterogeneity. 1 Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK. 2 Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, 10115 Berlin, Germany. 3 School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK. 4 Institut -
A Subadult Individual of Styracosaurus Albertensis
Vertebrate Anatomy Morphology Palaeontology 8:67–95 67 ISSN 2292-1389 A subadult individual of Styracosaurus albertensis (Ornithischia: Ceratopsidae) with comments on ontogeny and intraspecific variation inStyracosaurus and Centrosaurus Caleb M. Brown1,*, Robert B. Holmes2, Philip J. Currie2 1Royal Tyrrell Museum of Palaeontology, Box 7500, Drumheller, AB, T0J 0Y0, Canada; [email protected] 2Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2E9, Canada; [email protected]; [email protected] Abstract: Styracosaurus albertensis is an iconic centrosaurine horned dinosaur from the Campanian of Alberta, Canada, known for its large spike-like parietal processes. Although described over 100 years ago, subsequent dis- coveries were rare until the last few decades, during which time several new skulls, skeletons, and bonebeds were found. Here we described an immature individual, the smallest known for the species, represented by a complete skull and fragmentary skeleton. Although ~80% maximum size, it possesses a suite of characters associated with immaturity, and is regarded as a subadult. The ornamentation is characterized by a small, recurved, but fused nasal horncore; short, rounded postorbital horncores; and short, triangular, and flat parietal processes. Using this specimen, and additional skulls and bonebed material, the cranial ontogeny of Styracosaurus is described, and compared to Centrosaurus. In early ontogeny, the nasal horncores of Styracosaurus and Centrosaurus are thin, recurved, and unfused, but in the former the recurved morphology is retained into large adult size and the horncore never develops the procurved morphology common in Centrosaurus. The postorbital horncores of Styracosaurus are shorter and more rounded than those of Centrosaurus throughout ontogeny, and show great- er resorption later in ontogeny. -
A Battering Ram?
A Battering Ram? All evidence suggests that Pachycephalosaur skulls were built to withstand extreme forces 9 inches of solid bone Bone organized in a radial arrangement- structural support Articulation btw back of skull and vertebrae oriented to transfer forces linearly Articulation btw back of skull and vertebral column built to withstand sideways forces Vertebral column has tongue and groove articulations Spinal column is an S-shaped shock absorber BUT There is no ‘locking’ mechanism on skull to keep battering heads aligned Some Pachycephalosaurs have imprinted blood vessels on dome These factors suggests that head- butting may not be likely Intraspecies Competition (typically male-male) Females are typically choosey Why? Because they have more to loose Common rule in biology: Females are expensive to lose, males are cheap (e.g. deer hunting) Females choose the male most likely to provide the most successful offspring Males compete with each other for access to female vs. female chooses the strongest male Choosey females // Strong males have more offspring => SEXUAL selection Many ways to do this... But: In general, maximize competition and minimize accidental deaths (= no fitness) http://www.youtube.com/watch?v=PontCXFgs0M http://www.metacafe.com/watch/1941236/giraffe_fight/ http://www.youtube.com/watch? http://www.youtube.com/watch?v=DYDx1y38vGw http://www.youtube.com/watch?v=ULRtdk-3Yh4 Air-filled horn cores vs. solid bone skull caps... Gotta have a cheezy animated slide. Homalocephale Pachycephalosaurus Prenocephale Tylocephale Stegoceras Head butting Pachycephalosaurs Bone structure was probably strong enough to withstand collision Convex nature would favor glancing blows Instead, dome and spines seem better suited for “flank butting” So..