A Statistical Analysis of Marine Mammal Dispersal Routes Across Major Ocean Regions Using Beta Diversity at the Generic Level A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at George Mason University By Carlos Mauricio Peredo Bachelor of Science Seton Hill University, 2012 Director: Mark D. Uhen, Assistant Professor Department of Atmospheric, Oceanic and Earth Sciences Spring Semester 2015 George Mason University Fairfax, VA Copyright 2015 Carlos Mauricio Peredo All Rights Reserved ii DEDICATION Dedicated to my wonderful parents, Mauricio and Julie Peredo, who left behind everything they knew and started fresh in a foreign land purely in the pursuit of a better life for their children; to my older brother Miguel, whose witty humor, eternal optimism, and fierce loyalty has kept my head above water and a smile on my face throughout countless tribulations; to my younger brother Julio, who has far surpassed us all in talent and intellect, and who inspires me to never stop learning; and most of all, to my loving wife Molly, who has never stopped believing in me and drives me to settle for nothing less than perfection. iii ACKNOWLEDGEMENTS I would like to thank my committee members, Drs. George, Lyons, and Parsons, for their tireless revisions and hard work on my behalf. I would like to thank George Mason University and the Smithsonian Institution for providing the support and inspiration for much of this project. I would like to thank the Paleobiology Database, and all of its contributors, for their ambitious vision and their relentless pursuit of its execution. I would like to thank my fellow members of the Uhen lab, who were always willing to advise, revise, and even commiserate. And above all, I would like to thank my advisor, Dr. Mark D. Uhen, who took a chance on a young man from a small university in rural Pennsylvania and helped mold the beginnings of his career. iv TABLE OF CONTENTS Page List of Tables ..................................................................................................................... vi List of Figures ................................................................................................................... vii List of Equations .............................................................................................................. viii List of Abbreviations and Symbols .................................................................................... ix Abstract ............................................................................................................................... x Introduction ......................................................................................................................... 1 Hypotheses ........................................................................................................................ 23 Procedure/Methods ........................................................................................................... 25 Results ............................................................................................................................... 30 Discussion ......................................................................................................................... 37 Conclusions ....................................................................................................................... 56 Appendix I ........................................................................................................................ 58 Appendix II ....................................................................................................................... 74 Works Cited ...................................................................................................................... 82 v LIST OF TABLES Table Page 1. Breakdown of dataset by taxa ............................................................................ ……30 2. Theoretical dataset used to test Alroy’s F’ ............................................................... .38 3. Overlapping genera across the Pacific in the Oligocene and Miocene ..................... .42 4. Overlapping genera across the Pacific in the Pliocene ............................................. 44 5. Overlapping genera across the Strait of Gibraltar ...................................................... 46 6. Overlapping genera across the Central American Seaway ........................................ 48 7. Summary of the pull of the recent results .................................................................. 52 vi LIST OF FIGURES Figure Page 1. Prorastomids of the Middle Eocene ..................................................................... ……8 2. Evolution of Amazon Drainage Basin ...................................................................... .11 3. Breakdown of Types of Biodiversity ........................................................................ .17 4. Division of Ocean Regions ....................................................................................... .29 5. Number of Marine Mammal Occurrences by Ocean Region ................................... .31 6. Global Origination and Extinction ............................................................................ 32 7. Similarity Values in the Northern Hemisphere through Time ................................... 34 8. Correlation of Alroy’s F’ to SD ................................................................................. 36 9. Correlation of Alroy’s F’ to SD for a theoretical dataset ........................................... 39 10. Correlation of Alroy’s F’ to SD for a theoretical dataset with outliers removed .... 40 11. Similarity values in the MET ................................................................................... 45 12. Similarity values between NWA and NEP .............................................................. 47 13. Similarity between NWA, NEP, and ARC .............................................................. 49 14. Breakdown of the number of species in each genus ................................................ 51 vii LIST OF EQUATIONS PAGE 1. Jaccard Index ..................................................................................................... ……19 2. Sørensen-Dice Coefficient ........................................................................................ .19 3. Jaccard:Sørensen-Dice Equivalency ......................................................................... .20 4. Original Forbes Index ............................................................................................... 21 5. Alroy’s Corrected Forbes Index ................................................................................. 22 viii ABBREVIATIONS AND SYMBOLS PAGE Alroy’s Corrected Forbes Index ......................................................................................... F’ Antarctic Ocean ............................................................................................................ ANT Arctic Ocean ................................................................................................................. ARC Jaccard Index ....................................................................................................................... J East Indian Ocean ........................................................................................................... EIO Mean ................................................................................................................................... µ Mediterranean-Tethys Ocean ........................................................................................ MET Million years ago ............................................................................................................. Ma Northeast Atlantic Ocean .............................................................................................. NEA Northeast Pacific Ocean ................................................................................................. NEP Northwest Atlantic Ocean ............................................................................................ NWA Northwest Pacific Ocean ............................................................................................... NWP Southeast Atlantic Ocean ............................................................................................... SEA Southeast Pacific Ocean .................................................................................................. SEP Southwest Atlantic Ocean ............................................................................................. SWA Southwest Pacific Ocean ............................................................................................... SWP Standard Deviation .............................................................................................................. σ Sørensen-Dice Coefficient ............................................................................................... SD ix ABSTRACT A STATISTICAL ANALYSIS OF MARINE MAMMAL DISPERSAL ROUTES ACROSS MAJOR OCEAN REGIONS USING BETA DIVERSITY AT THE GENERIC LEVEL Carlos Mauricio Peredo, M. S. George Mason University, 2015 Thesis Director: Dr. Mark D. Uhen Using the Paleobiology Database, the distribution of marine mammal genera was analyzed across geologic time in an effort to isolate dispersal routes. Measurements of beta diversity were used to quantify