Megafauna

Gerry De Iuliis, Sergio F. Vizcaíno, Richard A. Fariña

Description

Really big animals and how they lived

More than 10,000 years ago spectacularly large mammals roamed the pampas and jungles of South America. This book tells the story of these great beasts during and just after the Pleistocene, the geological epoch marked by the great ice ages. Megafauna describes the history and way of life of these animals, their comings and goings, and what befell them at the beginning of the modern era and the arrival of humans. It places these giants within the context of the other mammals then alive, describing their paleobiology—how they walked; how much they weighed; their diets, behavior, biomechanics; and the interactions among them and with their environment. It also tells the stories of the scientists who contributed to our discovery and knowledge of these transcendent creatures and the environment they inhabited. The episode known as the Great American Biotic Interchange, perhaps the most important of all natural history "experiments," is also an important theme of the book, tracing the biotic events of both North and South America that led to the fauna and the ecosystems discussed in this book.

Prologue
1. Paleontology and Science: What is Science?
2. Distinguished Paleomammalogists
3. Geologic and Ecological History of South America During the Cenozoic Era
4. North American Late Cenozoic Faunas
5. The Great American Biotic Interchange and Pleistocene Habitats in South America
6. Bestiary
7. Physics of the Giants
8. General Paleoecology
9. Extinction
Appendix 1: A Primer on Skeletal Anatomy
Appendix 2: Skeletal Anatomy of Xenarthrans
Appendix 3: Equations Used to Estimate Body Masses Based on Dental and Skeletal Measurements and Their Respective Sources.
Appendix 4: Calculations
References
Index

Sujets

• Sciences de la nature
• Biologie
• Life Sciences
• Mammals
• Sciences et techniques
• Biology
• Zoology
• Paleontology
• Mammal
• Evolution
• Animals
• 454 Life Sciences
• Science

Informations

• Publié par: Indiana University Press
• Date de parution: 22 mai 2013
• Nombre de lectures: 0
• EAN13: 9780253007193
• Langue: English
• Poids de l'ouvrage: 5 Mo

Extrait

This book is a publication of
Indiana University Press
Office of Scholarly Publishing
Herman B Wells Library 350
1320 East 10th Street
Bloomington, Indiana 47405 USA
iupress.indiana.edu
Telephone orders 800-842-6796
Fax orders 812-855-7931
Orders by e-mail [e-mail]
2013 by Richard A. Fari a, Sergio F. Vizca no, and Gerardo De Iuliis
All rights reserved
No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and recording, or by any information storage and retrieval system, without permission in writing from the publisher. The Association of American University Presses Resolution on Permissions constitutes the only exception to this prohibition.
The paper used in this publication meets the minimum requirements of the American National Standard for Information Sciences- Permanence of Paper for Printed Library Materials, ANSI Z39.48-1992.
Manufactured in the United States of America
Library of Congress Cataloging-in-Publication Data
Megafauna : giant beasts of Pleistocene South America / Richard A. Fari a, Sergio F. Vizca no, and Gerry De Iuliis.
p. cm. - (Life of the past)
Includes bibliographical references and index.
ISBN 978-0-253-00230-3 (cloth : alk. paper) - ISBN 978-0-253-00719-3 (eb) 1. Mammals, Fossil-South America. 2. Paleobiology-South America. 3. Geology, Stratigraphic-Pleistocene. I. Fari a, Richard A. II. Vizca no, Sergio F. III. De Iuliis, Gerardo, [date]
QE881.M475 2012
569.098-dc23
2012017801
1 2 3 4 5 17 16 15 14 13
To past and current researchers of South American fossil mammals.
Those of the past are an endless source of inspiration, those still current of intellectual motivation.
To the memory of Mirta Tosar, my mother, who taught me to be bold and love animals as a person, and to Neill Alexander, who encouraged me in the same way as a scientist.
R.A.F.
To the memory of my parents, Eric and Negra, who instilled in me the value of hard work and honesty.
To Susi, Rulo, Leo, Tano, Guille, and Nestor, the people with whom I share every day the joy of doing this job.
S.F.V.
To my family and the memory of my father and father-in-law, whose sacrifices allowed me the luxury of doing what I love.
To Charles Rufus Churcher, who instilled in me the intellectual discipline to carry it out.
G.D.I.
The number of the remains embedded in the grand estuary deposit which forms the Pampas and covers the granitic rocks of Banda Oriental, must be extraordinarily great. I believe a straight line drawn in any direction through the Pampas would cut through some skeleton or bones. Besides those which I found during my short excursions, I heard of many others, and the origin of such names as the stream of the animal, the hill of the giant, is obvious. At other times I heard of the marvellous property of certain rivers, which had the power of changing small bones into large; or, as some maintained, the bones themselves grew. As far as I am aware, not one of these animals perished, as was formerly supposed, in the marshes or muddy river-beds of the present land, but their bones have been exposed by the streams intersecting the subaqueous deposit in which they were originally embedded. We may conclude that the whole area of the Pampas is one wide sepulchre of these extinct gigantic quadrupeds.
Charles R. Darwin, November 26, 1833
C
Contents
Preface Acknowledgments
1 Paleontology and Science: What Is Science?
2 Distinguished Paleomammalogists
3 Geological and Ecological History of South America during the Cenozoic Era
4 North American Late Cenozoic Faunas
5 The Great American Biotic Interchange and Pleistocene Habitats in South America
6 Bestiary
7 Physics of the Giants
8 General Paleoecology
9 Extinction
Epilogue. Lessons from the Deep Past
Appendix 1. A Primer on Skeletal Anatomy
Appendix 2. Skeletal Anatomy of Xenarthrans
Appendix 3. Equations Used to Estimate Body Masses Based on Dental and Skeletal Measurements and Their Respective Sources
Appendix 4. Calculations
References
Index
P
Preface Acknowledgments
The first reports, during the late 1700s and early 1800s, of the fossil remains of South America s magnificent Pleistocene beasts, so fantastically bizarre, immediately caused a stir among the general public and, in particular, the European scientific community. The first notices of their discovery described them as monsters, firing the imagination and interest of several eminent scientists and politicians, and leading some of them to believe that these great beasts still wandered among the unknown (for Europeans, at any rate) reaches of the New World. The fossils helped usher in a new episode among the fledgling nations of both South and North America, striving then for recognition and validation in the eyes of the established European powers: finally they had something of their own that rivaled the great treasures of the Old World. Eventually, the fossils contributed significantly to the establishment of new scientific institutions and traditions as the New World countries took hold of their destinies and exploration of their territories.
The fossil mammals of both North and South America began to reveal an unimagined chapter in the history of mammals, based as it then was mainly on knowledge unearthed from European deposits, but it was those from South America that were most strikingly different and garnered much of the early attention. Perhaps because of this distinctness, largely as a result of the long, past isolation of South America from other continental landmasses, they played crucial roles in the development of modern biological thought. We may note as examples of their scientific achievements that a South American fossil mammal ( Megatherium americanum, a giant fossil sloth) was the first fossil to be formally described and named scientifically, and its skeleton was the first to be mounted in a lifelike pose. The sharp mind of Georges Cuvier, the great French comparative anatomist, forged the concept of extinction (in the modern sense of this word) based on this fossil sloth (as well as on North and South American remains of fossil elephant relatives). Perhaps most significantly, it was the giant sloths, the giant armadillo-like glyptodonts, and the majestic and ponderous toxodonts (among other South American fossil remains) that struck most fervently upon the fertile mind of the young Charles Darwin, both during and after his famous voyage aboard the HMS Beagle, as he worked out his ideas on evolutionary theory.
Despite the relative isolation of the new South American countries, these ideas greatly affected scientists and intellectuals on both sides of the R o de la Plata, several of whom (such as the Ameghinos) took on the void created by Darwin s return to England and restarted the study of the South American fossil mammals with renewed enthusiasm. Such was their influence that it even affected the excited atmosphere of the newly born city of La Plata, which inspired an illustration that adorns one of the entrances of the Divisi n Paleontolog a de Vertebrados of the Museo de La Plata. As explained in Chapter 8 , it was conceived at the end of the nineteenth century, just after the city s founding, as an artist s rendition of a plan to embellish the gardens between the museum and the neighboring zoo, two of the proud city s new jewels. In these gardens, visitors could stroll between the institutions that housed the living and the long dead and have a sense of those extinct beasts, brought back to life in the form of life-sized sculptures.
Despite such an early and auspicious beginning, the study and our understanding of South America s extinct mammals has generally lagged behind those from most other continents. In part this is certainly due to their distinctness, generally leading scientists to either consider them too odd to expend much energy on, or regard them as somewhat inferior variants of more typical mammals, as was once done for dinosaurs. In accepting such views, the past was condemned to be more or less like the present and the magnificent mammals of South America relegated to being antiquated curiosities of better and more modern mammalian designs.
In this book we endeavor to reveal that such views are erroneous. Despite their differences and the fact that no living analogues exist for many native South American mammals, thus making comparisons difficult, we show that these mammals and the environments in which they lived and evolved were likely not merely slight variations of those that exist today. Their study is thus entirely worth the effort. By combining a wide variety of techniques from several biological disciplines, researchers over the past decade or so have begun bringing these beasts back to life. The picture that has begun to emerge is that of a marvelous biota that resists being pigeonholed, one that at once enlightens our concept of mammalness and enhances our knowledge of the past.
We begin our story in Chapter 1 with an introduction to the splendor of the South American megafauna, the assemblage of large-sized and gigantic beasts (or megamammals) that are the main subject of this book. In addition, we provide an analysis of how paleontology (and science in general) works, discussing its place among the evolutionary sciences, and consider other relevant background topics such as the role of fossilization, geology, and biological classification. This sets the stage for the more detailed discussions of the mammals and their environments provided in later chapters. We continue in Chapter 2 by outlining the historical contributions to the study of South America s fossil mammals: a pantheon of researchers whose efforts illuminate our present knowledge, for these are the giants on whose shoulders modern paleontologists stand. Chapter 3 provides more detailed discussions, begun in Chapter 1 , of the