DOCSLIB.ORG

Pouched Killers Not Poor Cousins of Carnivores 24 November 2010, by Bob Beale

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Pouched Killers Not Poor Cousins of Carnivores 24 November 2010, by Bob Beale Pouched killers not poor cousins of carnivores 24 November 2010, By Bob Beale most carnivorous niches on land. Today, these roles are mostly filled by placental meat-eaters, including such iconic species as the lion, tiger and grey wolf." Computer model of a placental lion skull used in the analysis. Researchers compared 33 measurements taken from the skulls of 62 different mammalian carnivores. Computer model of a marsupial lion skull used in the analysis. (PhysOrg.com) -- Marsupial predators are not the poor cousins of the carnivore world, as has long been thought: new research shows that they have "However, among the other major group of been just as diverse as placental carnivores over mammals, the pouched marsupials, predators are time. mostly small and few and far between. They display relatively little variation in shape or habit. Most are "We've looked at the deep-time perspective and found only in Australia and the largest - weighing shown that over evolutionary history marsupial only around 7 kilograms - is the Tasmanian devil, carnivores have been every bit as varied in shape which is now restricted to the Australian island of and habit as their placental counterparts," says Dr. Tasmania and under serious threat." Stephen Wroe, an author of a paper published in the journal Proceedings of the Royal Society B. The traditional explanation for this apparent lack of diversity has long been that the marsupial mode of "Their ranks have included creatures as bizarre as development, where the young are born at a very the Argentinean pouched sabretooth, which early stage, had seriously constrained their ability sported monstrous, self-sharpening canine teeth to adapt to new habits and environments. that extended almost back into its braincase, and Australia's own marsupial lion, which had teeth like "But if we consider species back through the last 60 bolt-cutters and the muscle power to match." million years or so it is clear that this was not always the case. For most of this time the "Throughout most of the Age of Mammals - a marsupial predator club contained a much wider period extending back some 65 million years - range of species that included some real giants, warm-blooded furry predators have dominated and the marsupials dominated South America - and 1 / 3 probably Antarctica - as well as Australia." More information: rspb.royalsocietypublishing.or … b.2010.2031.abstract Working with Anjali Goswami of University College London, and Nick Milne of the University of Western Australia, Wroe looked at data collected from museums on five continents, including Provided by University of New South Wales members of a wide range of living and extinct mammalian carnivore families. Applying an approach known as geometric morphometrics to map out and analyse whole skulls of living and fossil species, they showed that the variation in shape of marsupial carnivores was actually greater than that observed in placentals. Although superficially similar to the placental sabretoothed cats, like Smilodon fatalis, the extinct sabretoothed marsupial, Thylacosmilus atrox, shown here, is the only mammalian carnivore to have evolved ever-growing canines, making it one of the most formidable predators known in mammalian history. Image (c) UCL, Grant Museum of Zoology "It seems likely that the diversity in skull shape among marsupial carnivores reflects a diversity in lifestyle that once was quite comparable to that of placentals," says Dr. Wroe, an expert in mammalian carnivore evolution. "Our results reinforce my own conclusion that the lack of marsupial predators in the world today has more to do with bad luck than bad genes." 2 / 3 APA citation: Pouched killers not poor cousins of carnivores (2010, November 24) retrieved 1 October 2021 from https://phys.org/news/2010-11-pouched-killers-poor-cousins-carnivores.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. 3 / 3 Powered by TCPDF (www.tcpdf.org).
Load more

Recommended publications
  • What Technology Wants / Kevin Kelly
    WHAT TECHNOLOGY WANTS ALSO BY KEVIN KELLY Out of Control: The New Biology of Machines, Social Systems, and the Economic World New Rules for the New Economy: 10 Radical Strategies for a Connected World Asia Grace WHAT TECHNOLOGY WANTS KEVIN KELLY VIKING VIKING Published by the Penguin Group Penguin Group (USA) Inc., 375 Hudson Street, New York, New York 10014, U.S.A. Penguin Group (Canada), 90 Eglinton Avenue East, Suite 700, Toronto, Ontario, Canada M4P 2Y3 (a division of Pearson Penguin Canada Inc.) Penguin Books Ltd, 80 Strand, London WC2R 0RL, England Penguin Ireland, 25 St. Stephen's Green, Dublin 2, Ireland (a division of Penguin Books Ltd) Penguin Books Australia Ltd, 250 Camberwell Road, Camberwell, Victoria 3124, Australia (a division of Pearson Australia Group Pty Ltd) Penguin Books India Pvt Ltd, 11 Community Centre, Panchsheel Park, New Delhi - 110 017, India Penguin Group (NZ), 67 Apollo Drive, Rosedale, North Shore 0632, New Zealand (a division of Pearson New Zealand Ltd) Penguin Books (South Africa) (Pty) Ltd, 24 Sturdee Avenue, Rosebank, Johannesburg 2196, South Africa Penguin Books Ltd, Registered Offices: 80 Strand, London WC2R 0RL, England First published in 2010 by Viking Penguin, a member of Penguin Group (USA) Inc. 13579 10 8642 Copyright © Kevin Kelly, 2010 All rights reserved LIBRARY OF CONGRESS CATALOGING IN PUBLICATION DATA Kelly, Kevin, 1952- What technology wants / Kevin Kelly. p. cm. Includes bibliographical references and index. ISBN 978-0-670-02215-1 1. Technology'—Social aspects. 2. Technology and civilization. I. Title. T14.5.K45 2010 303.48'3—dc22 2010013915 Printed in the United States of America Without limiting the rights under copyright reserved above, no part of this publication may be reproduced, stored in or introduced into a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording or otherwise), without the prior written permission of both the copyright owner and the above publisher of this book.
    [Show full text]
  • Person, J.J. 2012. Saber Teeth. Geo News 39(2)
    Saber Teeth Jeff J. Person Carnivores of all kinds have always been of interest to me. Arguably Smilodon is only the last iteration of saber-teeth in the fossil it is a much more difficult lifestyle to hunt and kill another animal record. Carnivorous mammals with large sabers have appeared than it is to browse or graze on non-mobile plants. Carnivorous four times across unrelated groups of carnivorous mammals over animals have evolved to stalk and kill their prey in many, many the last 60 million years (or so) of Earth’s history. varied ways. Just think of the speed of a frog’s tongue or the speed of a cheetah, the stealth and camouflage of an octopus, Types of Saber-teeth or the intelligence of some birds. These are only a few examples Not only were there four different groups of mammals that of modern carnivores; the variety of carnivores through time is evolved saber-teeth separately, there are also two different kinds broader and even more fascinating. of saber-teeth. There are the dirk-toothed forms, and the scimitar- toothed forms. The scimitar-toothed animals tended to be more Convergent evolution is the reappearance of the same solution lightly built with coarsely serrated and somewhat elongated to a biological problem across unrelated groups of animals. This canines (fig. 1) (Martin, 1998a). The dirk-toothed animals tended has happened many times throughout Earth’s history. The similar to be more powerfully built with long, finely serrated, dagger-like body shapes of sharks, fish, ichthyosaurs (a group of swimming canines which sometimes included a large flange on the lower jaw reptiles) and dolphins is a great example of unrelated groups of (fig.
    [Show full text]
  • A Evolução Dos Metatheria: Sistemática, Paleobiogeografia, Paleoecologia E Implicações Paleoambientais
    UNIVERSIDADE FEDERAL DE PERNAMBUCO CENTRO DE TECNOLOGIA E GEOCIÊNCIAS PROGRAMA DE PÓS-GRADUAÇÃO EM GEOCIÊNCIAS ESPECIALIZAÇÃO EM GEOLOGIA SEDIMENTAR E AMBIENTAL LEONARDO DE MELO CARNEIRO A EVOLUÇÃO DOS METATHERIA: SISTEMÁTICA, PALEOBIOGEOGRAFIA, PALEOECOLOGIA E IMPLICAÇÕES PALEOAMBIENTAIS RECIFE 2017 LEONARDO DE MELO CARNEIRO A EVOLUÇÃO DOS METATHERIA: SISTEMÁTICA, PALEOBIOGEOGRAFIA, PALEOECOLOGIA E IMPLICAÇÕES PALEOAMBIENTAIS Dissertação de Mestrado apresentado à coordenação do Programa de Pós-graduação em Geociências, da Universidade Federal de Pernambuco, como parte dos requisitos à obtenção do grau de Mestre em Geociências Orientador: Prof. Dr. Édison Vicente Oliveira RECIFE 2017 Catalogação na fonte Bibliotecária: Rosineide Mesquita Gonçalves Luz / CRB4-1361 (BCTG) C289e Carneiro, Leonardo de Melo. A evolução dos Metatheria: sistemática, paleobiogeografia, paleoecologia e implicações paleoambientais / Leonardo de Melo Carn eiro . – Recife: 2017. 243f., il., figs., gráfs., tabs. Orientador: Prof. Dr. Édison Vicente Oliveira. Dissertação (Mestrado) – Universidade Federal de Pernambuco. CTG. Programa de Pós-Graduação em Geociências, 2017. Inclui Referências. 1. Geociêcias. 2. Metatheria . 3. Paleobiogeografia. 4. Paleoecologia. 5. Sistemática. I. Édison Vicente Oliveira (Orientador). II. Título. 551 CDD (22.ed) UFPE/BCTG-2017/119 LEONARDO DE MELO CARNEIRO A EVOLUÇÃO DOS METATHERIA: SISTEMÁTICA, PALEOBIOGEOGRAFIA, PALEOECOLOGIA E IMPLICAÇÕES PALEOAMBIENTAIS Dissertação de Mestrado apresentado à coordenação do Programa de Pós-graduação
    [Show full text]
  • 108 ©2017 by the Society of Vertebrate Paleontology
    Technical Session XII (Friday, August 25, 2017, 11:15 AM) We present the first comprehensive exploration of body size evolution in all major amniote clades during the Permo-Triassic (PT). Using phylogenetic comparative methods ELSHAFIE, Sara J., UC Berkeley, Berkeley, CA, United States of America that allow for rate variation we examined evolutionary rates in parareptiles, Caudal autotomy, the ability to shed the tail, is common among lizards as a defense archosauromorphs and therapsids. mechanism to escape predation. Caudal autotomy is a basal synapomorphy of Models that allow for rate variation between different branches outperform homogeneous Lepidosauria. About two-thirds of extant lizard families include species that retain the rate models for Parareptilia. Early diverging parareptiles experienced low evolutionary ability. Many can also regenerate the tail after shedding it. The oldest known fossil rates but rates increased to normal with the emergence of the first Ankyramorpha, as evidence of caudal autotomy in a reptile comes from early Permian captorhinids. Here I expected from a Brownian model of evolution. Evolutionary rates accelerated further report the earliest and only documented evidence of caudal autotomy for Squamata, in a with the appearance of the pareiasaurs and peaked within procolophonids at the PT glyptosaurine specimen from the early middle Eocene Bridger Formation in the Bridger boundary. Rates then plateaued in the Triassic, being an order of magnitude higher than Basin of southwestern Wyoming. normal rates. I identified signs of caudal autotomy in this specimen based on disproportions in an intact A heterogeneous rate model is also favoured for Therapsida. Early diverging members of 1.5-cm segment of the tail.
    [Show full text]
  • Caudal Cranium of Thylacosmilus Atrox (Mammalia, Metatheria, Sparassodonta), a South American Predaceous Sabertooth
    CAUDAL CRANIUM OF THYLACOSMILUS ATROX (MAMMALIA, METATHERIA, SPARASSODONTA), A SOUTH AMERICAN PREDACEOUS SABERTOOTH ANALÍA M. FORASIEPI, ROSS D. E. MACPHEE, AND SANTIAGO HERNANDEZ DEL PINO BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY CAUDAL CRANIUM OF THYLACOSMILUS ATROX (MAMMALIA, METATHERIA, SPARASSODONTA), A SOUTH AMERICAN PREDACEOUS SABERTOOTH ANALÍA M. FORASIEPI IANIGLA, CCT-CONICET, Mendoza, Argentina ROSS D.E. MacPHEE Department of Mammalogy, American Museum of Natural History, New York SANTIAGO HERNÁNDEZ DEL PINO IANIGLA, CCT-CONICET, Mendoza, Argentina BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY Number 433, 64 pp., 27 figures, 1 table Issued June 14, 2019 Copyright © American Museum of Natural History 2019 ISSN 0003-0090 CONTENTS Abstract.............................................................................3 Introduction.........................................................................3 Materials and Methods................................................................7 Specimens . 7 CT Scanning and Bone Histology....................................................8 Institutional and Other Abbreviations ...............................................12 Comparative Osteology of the Caudal Cranium of Thylacosmilus and Other Sparassodonts . .12 Tympanic Floor and Basicranial Composition in Thylacosmilus . 12 Tympanic Floor Composition in the Comparative Set .................................19 Petrosal Morphology..............................................................26 Tympanic Roof Composition
    [Show full text]
  • Mammalia, Metatheria, Sparassodonta) from the Miocene of Patagonia, Argentina
    Zootaxa 2552: 55–68 (2010) ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ Article ZOOTAXA Copyright © 2010 · Magnolia Press ISSN 1175-5334 (online edition) A new thylacosmilid (Mammalia, Metatheria, Sparassodonta) from the Miocene of Patagonia, Argentina ANALÍA M. FORASIEPI1 & ALFREDO A. CARLINI2 1Departamento de Paleontología, Museo de Historia Natural de San Rafael, Parque Mariano Moreno s/n (5600), San Rafael, Mendoza, Argentina. E-mail: [email protected] 2Departamento de Paleontología, Museo de La Plata, Paseo del Bosque s/n (1900), La Plata, Buenos Aires, Argentina. E-mail: [email protected] Abstract A new genus and species, Patagosmilus goini, of the family Thylacosmilidae (Mammalia, Metatheria, Sparassodonta) is described here. The new taxon is based on a single specimen collected from the west margin of the Río Chico, in Río Negro Province, Argentina, from the middle Miocene Colloncuran SALMA. Until now, two formally recognized species were encompassed in the family Thylacosmilidae: Thylacosmilus atrox, from the late Miocene-late Pliocene Huayquerian to Chapadmalalan SALMAof Argentina and probably Uruguay; and Anachlysictis gracilis, from the middle Miocene Laventan SALMA of Colombia. Recognition of the Patagonian taxon, Patagosmilus, provides new anatomical data, likely to be included in future phylogenetic analyses. The overall morphology of Patagosmilus suggests that it has a more generalized anatomy than Thylacosmilus. The dental morphology suggests the new Patagonian taxon was probably closer to Thylacosmilus than Anachlysictis. Saber-tooth thylacosmilids have several autapomorphic features in the skull that differentiate them from other sparassodonts, including the delayed replacement or non-replacement of the deciduous last premolar. Key words: saber-tooth metatherians, Cenozoic, South America Introduction The family Thylacosmilidae (Mammalia, Metatheria, Sparassodonta) has one of the most bizarre morphologies among the native Neogene predators of South America.
    [Show full text]
  • Sabre Tooth Free
    FREE SABRE TOOTH PDF Peter O'Donnell | 288 pages | 01 Sep 2003 | Souvenir Press Ltd | 9780285636767 | English | London, United Kingdom 12 Amazing Saber-Toothed Animals | Live Science Sabre Tooth saber-toothed cat may be the most famous saber-toothed animal, but it's hardly the only one. More than a dozen kinds of animals — many of them now extinct — had saber teeth, including the saber-toothed salmon and the marsupial Thylacosmilus. Today, saber-toothed animals include the walrusmusk deer and warthog, all of which grow incredibly long and sharp canines, the hallmark of a saber tooth. Elephant tusks are long incisor teeth, and thus are not sabers. It's unclear how ancient animals used their saber teeth. The teeth would have broken as the prey bucked around. Instead, perhaps the sabers helped predators tear away at the prey's belly. He added, "Sorry for the graphic details, but this is what happens, and it is supremely effective. The musk deer Moschus moschiferus is Sabre Tooth of the few saber-toothed animals living Sabre Tooth. But it doesn't use its long canines for meaty prey — the ungulate is an herbivore, said Jack Tseng, a paleontologist at the AMNH. The walrus Odobenus rosmarus has one of the longest sabers on record, with some males Sabre Tooth canines extending more than a foot 0. Male walruses use Sabre Tooth sabers both as a display and a weapon, Tseng said. The sabers serve a variety of purposes. These long canines help them with "tooth-walking," or pulling their large bodies out of the water; breaking breathing holes in ice while swimming in the water below; and protecting their territory and Sabre Tooth, according to National Geographic.
    [Show full text]
  • This Is the Time Frame in Which Mammal Lineages
    At 94 million years ago, Gondwana has started rifting apart, with Africa and India the first to break away. or This is the time frame in which mammal lineages are Marsupials appeared in Asia, but they managed to diversifying—Asiatherium, for example, is a Late disperse all the way to Australia, via island chains and Cretaceous marsupial from Mongolia. land bridges. 1 Placental mammals are as Australia still has no old as marsupials, but the native placental few placental lineages that mammals (except for dispersed by land to bats, marine Australia, while that was mammals, and species still possible, died out introduced by there. Marsupials, humans), and the however, radiated into marsupials have forms like the 25 million- radiated into a year-old Ngamaroo, kin to remarkable diversity kangaroos (top) and the of forms, many of 10-20-million year-old which are convergent Ekaltadeta, a galloping, on placental predatory “killer mammals. kangaroo” (bottom) Both marsupials and Marsupials unique to placental mammals South America reached South America, included but not all modern orders Thylacosmilus, of mammals made it. convergent on the Other orders of mammals more famous “saber- evolved in isolation from toothed cats” but not the rest of the world, related—this is a including the vaguely marsupial, not a elephant-like pyrotheres placental mammal! (top), and the In fact, the “saber- notoungulates, which tooth” form evolved ranged from rhino-like convergently at least beasts to the rabbit-like four times in Propachyrukhos (bottom). mammal evolution. 2 The mammal lineages that reached South America also radiated into unique forms that are still with us.
    [Show full text]
  • New Specimens of Sparassodonta (Mammalia, Metatheria) From
    NEW SPECIMENS OF SPARASSODONTA (MAMMALIA, METATHERIA) FROM CHILE AND BOLIVIA by RUSSELL K. ENGELMAN Submitted in partial fulfillment of the requirements for the degree of Master of Science Department of Biology CASE WESTERN RESERVE UNIVERSITY January, 2019 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of Russell K. Engelman candidate for the degree of Master of Science*. Committee Chair Hillel J. Chiel Committee Member Darin A. Croft Committee Member Scott W. Simpson Committee Member Michael F. Benard Date of Defense July 20, 2018 *We also certify that written approval has been obtained for any proprietary material contained therein. ii TABLE OF CONTENTS NEW SPECIMENS OF SPARASSODONTA (MAMMALIA, METATHERIA) FROM CHILE AND BOLIVIA ....................................................................................................... i TABLE OF CONTENTS ................................................................................................... iii LIST OF TABLES ............................................................................................................. vi LIST OF FIGURES .......................................................................................................... vii ACKNOWLEDGEMENTS ................................................................................................ 1 LIST OF ABBREVIATIONS ............................................................................................. 4 ABSTRACT .......................................................................................................................
    [Show full text]
  • Biomechanics of Felid Skulls: a Comparative Study Using Finite Element Approach
    Biomechanics of felid skulls: A comparative study using finite element approach Uphar Chamoli Supervisor: Dr. Stephen Wroe Submitted in partial fulfilment of the requirements for the degree of Master of Philosophy School of Biological, Earth and Environmental Sciences, Faculty of Science, The University of New South Wales August 2011 CERTIFICATE OF ORIGINALITY I hereby declare that this submission is my own work and to the best of my knowledge it contains no materials previously published or written by another person, nor material which to a substantial extent has been accepted for the award of any other degree or diploma at UNSW or any other educational institution, except where due acknowledgement is made in the thesis. Any contribution made to the research by others, with whom I have worked at UNSW or elsewhere is explicitly acknowledged in the thesis. I also declare that the intellectual content of this thesis is the product of my own work, except to the extent that assistance from others in the project's design and conception or in style, presentation and linguistic expression is acknowledged. Signature ...................... Date.............................. ii Dedicated to my parents and my deep rooted faith in Karma iii A major component of this thesis is published in Journal of Theoretical Biology x Chamoli, U. & Wroe, S., 2011. Allometry in the distribution of material properties and geometry of the felid skull: Why larger species may need to change and how they may achieve it. Journal of Theoretical Biology 283(1):217- 226. Some of the other methodologies used in this project, OR developed during the course of this project are also published in following journals x Attard, M., Chamoli, U., Ferrara, T., Rogers, T., and Wroe, S., 2011.
    [Show full text]
  • A New Tribe of Saber-Toothed Cats (Barbourofelini) from the Pliocene of North America C
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Bulletin of the University of Nebraska State Museum, University of Nebraska State Museum 1970 A New Tribe of Saber-toothed Cats (Barbourofelini) from the Pliocene of North America C. Bertrand Schultz Marian R. Schultz Larry D. Martin Follow this and additional works at: http://digitalcommons.unl.edu/museumbulletin Part of the Entomology Commons, Geology Commons, Geomorphology Commons, Other Ecology and Evolutionary Biology Commons, Paleobiology Commons, Paleontology Commons, and the Sedimentology Commons This Article is brought to you for free and open access by the Museum, University of Nebraska State at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Bulletin of the University of Nebraska State Museum by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. BULLETIN OF VOLUME 9, NUMBER 1 The University of Nebraska State Museum OCTOBER. 1970 C. Bertrand Schultz Marian R. Schultz Larry D. Martin A New Tribe of Saber-Toothed Cats (Barbourofelini) from the Pliocene of North America Frontispiece.-Barbourofelis fricki, new genus and species, holotype, U.N.S.M. 76000, skull and mandibular ramus, from the Kimball Formation (very late Pliocene), Frontier County, Nebraska. X 1/2. C. Bertrand Schultz Marian R. Schultz Larry D. Martin A New Tribe of Saber-toothed Cats (Barbourofelini) from the Pliocene of North America BULLETIN OF The University of Nebraska State Museum VOLUME 9, NUMBER 1 OCTOBER, 1970 BULLETIN OF VOLUME 9, NUMBER 1 THE UNIVERSITY OF NEBRASKA STATE MUSEUM OCTOBER, 1970 Pp. 1-31, Table 1-2 Frontispiece, Figs. 1-13 ABSTRACT A New Tribe of Saber-toothed Cats (Barbourofelini) from the Pliocene of North America c.
    [Show full text]
  • Deep Time Diversity of Metatherian Mammals: Implications for Evolutionary History and Fossil-Record Quality
    Paleobiology, 44(2), 2018, pp. 171–198 DOI: 10.1017/pab.2017.34 Deep time diversity of metatherian mammals: implications for evolutionary history and fossil-record quality C. Verity Bennett, Paul Upchurch, Francisco J. Goin, and Anjali Goswami Abstract.—Despite a global fossil record, Metatheria are now largely restricted to Australasia and South America. Most metatherian paleodiversity studies to date are limited to particular subclades, time intervals, and/or regions, and few consider uneven sampling. Here, we present a comprehensive new data set on metatherian fossil occurrences (Barremian to end Pliocene). These data are analyzed using standard rarefaction and shareholder quorum subsampling (including a new protocol for handling Lagerstätte-like localities). Global metatherian diversity was lowest during the Cretaceous, and increased sharply in the Paleocene, when the South American record begins. Global and South American diversity rose in the early Eocene then fell in the late Eocene, in contrast to the North American pattern. In the Oligocene, diversity declined in the Americas, but this was more than offset by Oligocene radiations in Australia. Diversity continued to decrease in Laurasia, with final representatives in North America (excluding the later entry of Didelphis virginiana) and Europe in the early Miocene, and Asia in the middle Miocene. Global metatherian diversity appears to have peaked in the early Miocene, especially in Australia. Following a trough in the late Miocene, the Pliocene saw another increase in global diversity. By this time, metatherian biogeographic distribution had essentially contracted to that of today. Comparison of the raw and sampling-corrected diversity estimates, coupled with evaluation of “coverage” and number of prolific sites, demonstrates that the metatherian fossil record is spatially and temporally extremely patchy.
    [Show full text]