Ecology of the Cambrian Radiation EDITED BY ANDREY YU. ZHURAVLEV AND ROBERT RIDING Columbia University Press ■ New York 00-C1099-FM 8/10/00 2:01 PM Page iii Columbia University Press Publishers Since 1893 New York Chichester, West Sussex Copyright © 2001 Columbia University Press All rights reserved Library of Congress Cataloging-in-Publication Data The ecology of the Cambrian radiation / edited by Andrey Yu. Zhuravlev and Robert Riding. p. cm.—(Critical moments in paleobiology and earth history series) Includes bibliographical references and index. ISBN 0-231-10612-2 (cloth : alk. paper)— ISBN 0-231-10613-0 (pbk. : alk. paper) 1. Paleoecology—Cambrian. 2. Paleontology— Cambrian. 3. Geology, Stratigraphic—Cambrian. I. Zhuravlev, A. IU. (Andrei IUr’evich). II. Riding, Robert. III. Series. QE720 .E27 2000 560Ј.1723— dc21 00-063901 ᭺ ϱ Casebound editions of Columbia University Press books are printed on permanent and durable acid-free paper. Printed in the United States of America C 10 9 8 7 6 5 4 3 2 1 P 10 9 8 7 6 5 4 3 2 1 We dedicate this book to David Gravestock and Kirill Seslavinsky. 00-C1099-FM 08/23/2000 4:48 PM Page iv Acknowledgments vii 1. Introduction ■ Andrey Yu. Zhuravlev and Robert Riding 1 PART I. THE ENVIRONMENT 9 2. Paleomagnetically and Tectonically Based Global Maps for Vendian to Mid-Ordovician Time ■ Alan G. Smith 11 3. Global Facies Distributions from Late Vendian to Mid-Ordovician ■ Kirill B. Seslavinsky and Irina D. Maidanskaya 47 4. Did Supercontinental Amalgamation Trigger the “Cambrian Explosion”? ■ Martin D. Brasier and John F. Lindsay 69 5. Climate Change at the Neoproterozoic-Cambrian Transition ■ Toni T. Eerola 90 6. Australian Early and Middle Cambrian Sequence Biostratigraphy with Implications for Species Diversity and Correlation ■ David I. Gravestock and John H. Shergold 107 7. The Cambrian Radiation and the Diversification of Sedimentary Fabrics ■ Mary L. Droser and Xing Li 137 PART II. COMMUNITY PATTERNS AND DYNAMICS 171 8. Biotic Diversity and Structure During the Neoproterozoic-Ordovician Transition ■ Andrey Yu. Zhuravlev 173 9. Ecology and Evolution of Cambrian Plankton ■ Nicholas J. Butterfield 200 Contents 00-C1099-FM 8/10/00 2:01 PM Page v 10. Evolution of Shallow-Water Level-Bottom Communities ■ Mikhail B. Burzin, Françoise Debrenne, and Andrey Yu. Zhuravlev 217 11. Evolution of the Hardground Community ■ Sergei V. Rozhnov 238 12. Ecology and Evolution of Cambrian Reefs ■ Brian R. Pratt, Ben R. Spincer, Rachel A. Wood, and Andrey Yu. Zhuravlev 254 13. Evolution of the Deep-Water Benthic Community ■ T. Peter Crimes 275 PART III. ECOLOGIC RADIATION OF MAJOR GROUPS OF ORGANISMS 299 14. Sponges, Cnidarians, and Ctenophores ■ Françoise Debrenne and Joachim Reitner 301 15. Mollusks, Hyoliths, Stenothecoids, and Coeloscleritophorans ■ Artem V. Kouchinsky 326 16. Brachiopods ■ Galina T. Ushatinskaya 350 17. Ecologic Evolution of Cambrian Trilobites ■ Nigel C. Hughes 370 18. Ecology of Nontrilobite Arthropods and Lobopods in the Cambrian ■ Graham E. Budd 404 19. Ecologic Radiation of Cambro-Ordovician Echinoderms ■ Thomas E. Guensburg and James Sprinkle 428 20. Calcified Algae and Bacteria ■ Robert Riding 445 21. Molecular Fossils Demonstrate Precambrian Origin of Dinoflagellates ■ J. Michael Moldowan, Stephen R. Jacobson, Jeremy Dahl, Adnan Al-Hajji, Bradley J. Huizinga, and Frederick J. Fago 474 List of Contributors 495 Index 499 vi Contents 00-C1099-FM 8/10/00 2:01 PM Page vi We are indebted to the following specialist reviewers without whose help we could not have accomplished this task: Pierre Adam, Pierre Albrecht, J. Fredrik Bockelie, Gerard C. Bond, Derek E. G. Briggs, Paul Copper, Pierre Courjault-Radé, Mary L. Droser, Richard A. Fortey, Gerd Geyer, Roland Goldring, James W. Hagadorn, Sören Jensen, Viktor E. Khain, Tat’yana N. Kheraskova, Pierre D. Kruse, Ed Landing, John F. Lindsay, Jere H. Lipps, Dorte Mehl, Carl Mendelson, Timothy J. Palmer, Christopher R. C. Paul, John S. Peel, Martin Pickford, Leonid E. Popov, Lars Ramsköld, Robert L. Ripperdan, Philippe Schaeffer, Frederick R. Schram, J. John Sepkoski, Jr., Thomas Servais, Barry D. Webby, Graham L. Williams, Matthew A. Wills, Mark A. Wilson, and Grant M. Young. We are especially grateful to Françoise Debrenne, Mary Droser, and Alan Smith for help in the preparation of this volume. Françoise Pilard, Max Debrenne, and Henri Lavina assisted greatly in the finalization of many figures. AZ’s editing was facilitated by the Muséum National d’Histoire Naturelle, Paris. We thank our contributors, one and all, for their willingness to join us in this ven- ture and for their forbearance when we acted as editors are only too often prone to do. Last, but certainly not least, we thank Ed Lugenbeel, Holly Hodder, and Jonathan Slutsky at Columbia University Press, and Mark Smith and his colleagues at G&S Edi- tors, for their expert handling of both the book and us. Acknowledgments 00-C1099-FM 8/10/00 2:01 PM Page vii 00-C1099-FM 8/10/00 2:01 PM Page viii ECOLOGY OF THE CAMBRIAN RADIATION 00-C1099-FM 8/10/00 2:01 PM Page ix ECOLOGY OF THE CAMBRIAN RADIATION 00-C1099-FM 8/10/00 2:01 PM Page i 00-C1099-FM 8/10/00 2:01 PM Page x THE CAMBRIAN RADIATION, which commenced around 550 million years ago, arguably ranks as the single most important episode in the development of Earth’s marine biota. Diverse benthic communities with complex tiering, trophic webs, and niche partitioning, together with an elaborate pelagic realm, were established soon af- ter the beginning of the Cambrian period. This key event in the history of life changed the marine biosphere and its associated sediments forever. At first glance, abiotic factors such us climate change, transgressive-regressive sea level cycles, plate movements, tectonic processes, and the type and intensity of vol- canism appearverysignificant in the shaping of biotic evolution. We cansee howrapid rates of subsidence, as expressed in transgressive system tracts on the Australian cra- ton, selectively affected the diversity of organisms such as trace fossil producers, ar- chaeocyath sponges, and trilobites (Gravestock and Shergold—chapter 6); how glob- ally increased rates of subsidence and uplift accompanied dramatic biotic radiation by increasing habitat size and allowing phosphorus- and silica-rich waters to invade platform interiors (Brasier and Lindsay—chapter 4); how climatic effects, coupled with intensive calc-alkaline volcanism, at the end of the Middle Cambrian may have caused a shift from aragonite- to calcite-precipitating seas, providing suitable con- ditions for development of the hardground biota (Seslavinsky and Maidanskaya— chapter 3; Eerola—chapter 5; Guensburg and Sprinkle—chapter 19); how the re- organization of plate boundaries (Smith—chapter 2; Seslavinsky and Maidanskaya) created conditions for current upwelling, which may in turn have been responsible for the appearance and proliferation of acritarch phytoplankton and many Early Cam- brian benthic organisms (Brasier and Lindsay; Ushatinskaya— chapter 16; Moldowan et al.—chapter 21). However, biotic factors themselves played a remarkable role in the environmental changes that formed thebackground to theCambrian radiation. We see how, by means of biomineralization, shell beds and calcite debris contributed to the appearance of hardground communities (Droser and Li—chapter 7; Rozhnov—chapter 11); how CHAPTER ONE Andrey Yu. Zhuravlev and Robert Riding Introduction 01-C1099 8/10/00 2:02 PM Page 1 [...]... which places the base of the Cambrian at 570 Ma, but new high-precision U-Pb zircon dates suggest that it is closer to 545 Ma (Tucker and McKerrow 1995) The problem of relating the two scales is complicated by the fact that the base of the Tommotian was taken as the base of the Cambrian at 570 Ma in Harland et al 1990 Since then, the Nemakit-Daldynian has been placed in the Cambrian below the Tommotian,... 60Њ off the initial APWP Although data exist for Laurentia for most of the Cambrian and Neoproterozoic periods, the mean pole for 509 Ma is the oldest pole to have more than 30 determinations in the 60 m.y window Of the other poles, only the poles for 590 Ma and 719 Ma all lie within 40Њ of the mean pole and include 6 or more determinations The positions of the other mean poles form zigzags on the APWP... series of global maps for this interval based principally on paleomagnetic and tectonic data; recent novel suggestions about the relationships between Gondwana and Laurentia during this interval; the substantial revision to the age of the base of the Cambrian period and other early Paleozoic stratigraphic boundaries; and, of course, the great interest in the transition from the late Precambrian to the Cambrian. .. model, the thermal phase follows immediately on the stretching phase without a time break In the model there may be unconformities between the sediments deposited during faulting and those deposited later, but there is no time gap between the cessation of faulting and the onset of the thermal phase Thus, the Laurentian and other passive margin sequences that lack faulting probably lie outside the zone of. .. authors to be the same as the rock age: all magnetic overprints have been excluded In addition, only one paleomagnetic study has been accepted for each rock unit defined in the database The criteria used to select the “best” study from several on the same unit have included the number of sites, the scatter of the data, the magnetic tests, and the pole position relative to other poles of the same age... aspects of their ecology are discussed within analyses of particular communities Not all the views expressed in this book are in agreement, nor should they be We hope that comparison of the facts, arguments, and ideas presented will allow the reader to judge the relative importance of abiotic and biotic factors on the dramatic evolutionary and ecologic expansion that was the Cambrian radiation of marine... from the ages assigned to them One argument in favor of this approach is that there is no significant difference in the mean pole position of high and low Q data for poles of the past 2.5 m.y.: only the scatter of global data increases for lower Q (Smith 1997) The most important selection criterion used here is that, for the poles selected, the age of the primary magnetization is considered by the authors... orogenic belts (Wooler et al 1992) In the absence of quantitative analyses, the time of separation may be difficult to estimate Extensional faulting that preceded the formation of ocean floor and the separation of two continents may span some tens of millions of years, as in the present East African rift The succeeding thermal phase, during which the margin subsides and the postrift passive margin sequence... areas there exists at present only the “fragments of a synthesis.” A quite different synthesis for Paleozoic Asia has been proposed by Mossakovsky et al (1994) The outlines of the Altaid and Manchurid fragments recognized by Sengör and Natal’in ¸ (1996) are shown on all the maps Because there is no agreement on the location of these fragments, they have been “parked” with their present-day shapes and positions... between the positions of the paleomagnetic poles on the reassemblies of Gondwana and Laurentia made using the rotations cited above and most others that exist in the literature The rotations for reassembling the smaller fragments are based on interpretations of the geologic and faunal data, discussed below The basic assumption for making global reconstructions from paleomagnetic data is that the continents . and there are data on biomarkers. COMMUNITY The theme of community considers the biotas in their ecologic context, from their di- versification to the development. 8/10/00 2:01 PM Page viii ECOLOGY OF THE CAMBRIAN RADIATION 00-C1099-FM 8/10/00 2:01 PM Page ix ECOLOGY OF THE CAMBRIAN RADIATION 00-C1099-FM 8/10/00 2:01 PM