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Proquest Dissertations Advances in the isotopic analysis of biogenic phosphates and their utility in ecophysiological studies of aquatic vertebrates Item Type text; Dissertation-Reproduction (electronic) Authors Roe, Lois Jane, 1963- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 02/10/2021 18:00:21 Link to Item http://hdl.handle.net/10150/282639 INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter fece, while others may be from any type of computer printer. The quality of this reproductioii is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely afreet reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper lefr-hand comer and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. UMI A Bell & Howell Infoimation Company 300 North Zeeb Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/521-0600 ADVANCE:: IN H IE ISOTOPIC ANALYSIS OF BIOGENIC PI lOSPI lATES AND rilEIK UTILITY IN ECOPHYSIOLOGICAL STUDIES OF AQUATIC VERTEBRATES by Lois Jane Roc Copyright © Lois Jane Roc 1998 A Dissertation Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fuinilmcnl of the Rcquircnicnls For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 1998 UMI Niimber: 9829380 Copyright 1998 by- Roe, Lois Jem.e All rights reserved. UMI Microform 9829380 Copyright 1998, by UMI Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. UMI 300 North Zeeb Road Ann Arbor, MI 48103 2 THE UNIVERSITY OF ARIZONA fi. GRADUATE COLLEGE As members of the Final Examination Committee, we certify that we have read the dissertation prepared by Lois Jane Roe entitled Advances in the Isotopic Analysis of Biogenic Phosphates and their Utility in Ecophysioloaical Studies of Aquatic Vertebrates and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy (2aa4U;C^ 3. ! 0-9^ • Marl^D. BajT^n Date feJ. Jg y99^ Everett H. Liffasay Date puh O '6/zz^p==:> 7-/j- , _ , A Date 3- 2^0-^9 s y • I,AMC Date Final approval and acceptance of this dissertation is contingent upon the candidate's submission of the final copy of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. Qu^L.—• J. 10. "jS . D^ ition Director jay Quade Date 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate ackowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the copyright holder. SIGNED: ACKNOWLEDGMENTS Many individuals, institutions and organizations supported this work financially, logistically, and intellectually. For their support of the fieldwork that made possible the whale study, I would like to thank the Geological Survey of Pakistan, its Director General, Dr. M. T. Hassan, Assistant Director M. Arif, and Dr. S. M. Raza of the Oil and Gas Development Corporation. Financial support of fieldwork and laboratory work was provided by grants to Hans Thewissen from the National Geographic Society, the National Science Foundation (EAR-9526686), and the Pioneer Fund of the Northeastern Ohio Universities College of Medicine and by research grants from the Society of Vertebrate Paleontology and the Geological Society of America to me. Financial support of for this research was also provided by an NSF-funded Fellowship from the University of Arizona Research Training Group for the Analysis of Biological Diversification to me, and by National Science Foundation Awards EAR-9005717 to Jim O'Neil, and EAR- 9418207 to Jay Quade. I am also grateful to all those who furnished modem specimens for analysis. For technical assistance, I thank H. Achyuthan for helping with the wet chemistry, and T. Moore, D. Smith, and D. Surge for assistance with illustrations. I wish to thank my committee, M. D. Barton, P. A. Hastings, E. H. Lindsay, J. G. Lundberg, and J. Quade, and for their help and guidance, and N. Lifton for many helpful discussions. Finally, I want to convey a special thanks to Hans Thewissen for giving me the opportunity and support to test my ideas on his rare and precious cetacean specimens, and to Jim O'Neil, for encouraging me to explore my interests in applying isotopes to paleophysiology. For the continued encouragement, financial and intellectual support of both of these individuals over the last ten years, I am most profoundly grateful. DEDICATION This dissertation is dedicated to my parents, George and Barbara Roe, for never asking me what I was going to do with a degree in geology and for their unwavering financial, logistical and emotional support over many years of education, and to the memory of the late Thomas Hoering, who was instrumental in helping me get started in my isotopic studies of biogenic phosphates. 6 TABLE OF CONTENTS TITLE PAGE 1 APPROVAL FORM 2 STATEMENT BY AUTHOR 3 ACKNOWLEDGMENTS 4 DEDICATION 5 TABLE OF CONTENTS 6 ABSTRACT 8 CHAPTER L INTRODUCTION 10 The Importance of Distinguishing Marine and Freshwater Animals in the Fossil Record 10 The Environment of Vertebrate Origins 11 The Importance of Marine-Freshwater Distinctions in Biogeography 12 Osmoregulation, Environmental Change and Mass Extinctions 13 Methods F*reviously Used to Make Marine-Freshwater Distinctions 15 A New Approach to Making Marine-Freshwater Distinctions 16 Format of this Dissertation 16 CHAPTER 2. PRESENT STUDY 20 Summary of Appendix A: Early Evolution of Cetacean Osmoregulation 20 Summary of Appendix B: Recognizing Phosphate Diagenesis 21 Summary of Appendix C: A New Method for Determining 6 23 7 TABLE OF CONTENTS - Continued APPENDIX A: ISOTOPIC APPROACHES TO UNDERSTANDING THE TERRESTRIAL TO MARINE TRANSITION OF THE EARLIEST CETACEANS 25 APPENDIX B: THE ISOTOPIC COMPOSITION OF CARBONATE AND PHOSPHATE IN THE BONES AND TEETH OF AQUATIC VERTEBRATES: SIGNIHCANCE FOR RECOGNIZING DIAGENESIS AND UNDERSTANDING MARINE MAMMAL PHYSIOLOGY 96 APPENDIX C: EXCHANGE BETWEEN CO2 AND Ag3P04 AT HIGH TEMPERATURES: A NEW METHOD FOR DETERMINING THE OXYGEN ISOTOPE COMPOSITION OF PHOSPHATIC MATERIALS 130 REFERENCES 155 8 ABSTRACT Distinguishing marine and freshwater animals in the fossil record is a long-standing problem in paleontology. The physiological tolerances of extinct animals usually are inferred from environmental indicators and/or on the physiology of nearest living relatives. These types of evidence are often ambiguous and may be confounded by factors such as post-mortem transport and polymorphism in the living relatives. A solution to this problem is to combine these types of data with analyses of the oxygen isotope compositions of the phosphate (6^^p) and the carbon isotope compositions of the carbonate (6^^sc) of teeth and bones, to determine whether the ingested water and diet, respectively, were fresh or marine. The power of this approach is illustrated here in a study of the early evolution of cetaceans (whales, dolphins and porpoises). Changes in 6 and 6^^sc of the teeth and bones of early cetaceans documented here indicate that fully marine cetaceans existed by the middle Eocene and that some species exploited both marine and freshwater environments. This isotopic approach requires the avoidance of isotopically altered specimens. For this reason, the second component of this work deals with criteria for recognizing isotopically altered fossils. In contrast to one recent study, 1 found a positive correlation between and 6^^sc not only in mammals but also in fish and reptiles. This correlation can be used as a test of whether the original isotopic composition is preserved in fossil specimens. Another approach to this problem is to make analyses of samples taken along growth transect of a fossil tooth or bone. Gorwth-transect analyses could resolve whether within-species isotopic variation represents differences in preservation or ontogenetic shifts in diet or habitat. In support of this goal, a new method for the analysis of phosphate oxygen is presented. This new method differs from all previous methods in that it involves no chemical reaction, but rather high-temperature (>725°C) equilibrium oxygen isotope exchange between CO2 and AgsPOLj. As the amount of CO2 is controlled 9 by the analyst, small phosphate samples may be analyzed, making this method potentially useful for growth-transect analyses. 10 CHAPTER 1.
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