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Mass Extinction Ashraf M Mass Extinction Ashraf M. T. Elewa Mass Extinction Ashraf M. T. Elewa Minia University Fac. Science Dept. Geology Minia 61519 Egypt [email protected] ISBN: 978-3-540-75915-7 e-ISBN: 978-3-540-75916-4 Library of Congress Control Number: 2007938882 c 2008 Springer-Verlag Berlin Heidelberg This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable for prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Cover design: deblik, Berlin Printed on acid-free paper 987654321 springer.com Dedication This book is dedicated to my mother In fact, she is one of the great women who could give an excellent example of how eastern women can be effective, like western women, in developing their societies Foreword P. David Polly Department of Geological Sciences, Indiana University, Bloomington, IN 47405, USA, [email protected] Only 200 years ago, extinction was a radical new idea. Fossils were known, but their identity as the remains of species that no longer lived on the face of the Earth was not yet firmly established in the scientific world. Arguments that these organic-looking objects from the rocks were merely bizarre mineralizations or that they were the remains of species still living in unexplored regions of the world had dominated 18th Century interpretations of fossils. But the settling of North America and other colonial expeditions by Europeans were quickly making the world smaller. In 1796 Cuvier painstakingly demonstrated that the anatomy of the mastodon skeleton from Big Bone Lick in Kentucky could not possibly belong to a modern elephant, unlike the mammoth fossils found in Europe, which are so similar to the living African Elephant that many found plausible the explanation that they were bones of animals used by the Roman army. Any doubt that Cuvier’s mastodon still lived in the wilds of the western North American interior was crushed ten years later when the Lewis and Clark expedition failed to find any sign of them. That fossils were the remains of extinct organisms revolutionized scientific understanding of the Earth and its history. The advent of stratigraphic geology in the early decades of the 19th Century brought the realization that there were sometimes major hiatuses in the continuity of life, when entire faunas and floras were replaced by others in the succession of rocks. Some of these hiatuses defined major boundaries in the geological timescale: the break between Permian and Jurassic periods became the dividing line between the Paleozoic and Mesozoic, and the turnover at the end of the Cretaceous became the division of Mesozoic from Cenozoic. Not only were many once living species now extinct, but they often perished together en masse. Quantitative work in the 1970s by Raup, Sepkoski, and others again revolutionized understanding of extinctions. Extinctions were periodic and massive, some of them like the end-Permian extinction wiping out 82% of the genera living at the time. Thanks to environmental geochemistry and other lines of evidence, we now understand that the Earth’s biota is complexly interlinked with cycles VIII P. David Polly of oxygen, carbon, erosion, tectonics, global temperature, sea level, and ecology. Living organisms are both affected by geoclimatic changes and help drive them. This new book edited by Prof. Ashraf Elewa presents a combination of reviews and original papers on several major extinctions: the Late Ordovician, the Late Devonian, the end Permian, the end Triassic, the end Cretaceous, and the Late Pleistocene extinctions. Elewa provides reviews of each of these, which are interspersed by original papers by international experts on each one, including Mikael Calner, Curtis Congreve, Ahmed Dakrory, Julien Louys, Spencer Lucas, Lawrence Tanner and Panos Petrakis, in addition to Elewa himself. The book concludes, appropriately, with papers on the current extinction that is being driving by the peopling of the Earth and the rapid environmental changes we have wrought. Table of Contents 1 Mass Extinction - a general view ...........................................................1 Ashraf M. T. Elewa References ............................................................................................4 2 Late Ordovician mass extinction ...........................................................5 Ashraf M. T. Elewa References ............................................................................................7 3 The End Ordovician; an ice age in the middle of a greenhouse .........9 Curtis R. Congreve 3.1 Introduction ....................................................................................9 3.2 Early research: The discovery of the glacial period .....................10 3.3 Fast or slow: The changing face of the Ordovician glaciation .....12 3.4 Trilobite extinction and larval form..............................................15 3.5 Future work...................................................................................17 3.6 Acknowledgements ......................................................................17 References ..........................................................................................18 4 Silurian global events – at the tipping point of climate change ........21 Mikael Calner 4.1 Introduction ..................................................................................21 X Table of Contents 4.2 The Silurian marine scene ............................................................24 4.3 Discovery of the Silurian global events........................................25 4.3.1 Early discoveries..................................................................27 4.3.2 The theory of Silurian oceanic events .................................28 4.3.3 The increased use of stable isotope stratigraphy .................29 4.4 The Early Silurian Ireviken Event ................................................31 4.4.1 Stratigraphic position...........................................................31 4.4.2 Groups affected....................................................................33 4.4.3 Stable isotopes .....................................................................34 4.4.4 Sedimentary changes and sea-level .....................................35 4.5 The Middle Silurian Mulde Event ................................................35 4.5.1 Stratigraphic position...........................................................36 4.5.2 Groups affected....................................................................37 4.5.3 Stable isotopes .....................................................................38 4.5.4 Sedimentary changes and sea-level .....................................38 4.6 The Late Silurian Lau Event.........................................................39 4.6.1 Stratigraphic position...........................................................40 4.6.2 Groups affected....................................................................40 4.6.3 Stable isotopes .....................................................................41 4.6.4 Sedimentary changes and sea-level .....................................42 4.7 Structure of the Silurian global events..........................................43 4.7.1 The Silurian events and carbonate platforms.......................43 4.7.2 Temporal and spatial development and biodiversity ...........45 4.7.3 Carbon isotope stratigraphy.................................................47 4.7.4 Sea-level change and sedimentary facies ............................48 4.7.5 Taxonomic vs ecologic events.............................................49 4.8 Summary.......................................................................................49 4.9 Acknowledgement........................................................................50 References ..........................................................................................50 5 Late Devonian mass extinction ............................................................59 Ashraf M. T. Elewa References ..........................................................................................60 6 Late Permian mass extinction..............................................................61 Ashraf M. T. Elewa Reference............................................................................................62 7 Late Triassic mass extinction...............................................................63 Ashraf M. T. Elewa References ..........................................................................................64 Table of Contents XI 8 Reexamination of the end-Triassic mass extinction...........................65 Spencer G. Lucas and Lawrence H. Tanner 8.1 Introduction ..................................................................................65 8.2 Late Triassic Timescale ................................................................66
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