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The Effects of Gopher Tortoise University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 5-21-2018 The ffecE ts of Gopher Tortoise (Gopherus polyphemus) Herbivory on Plant Community Composition and Seed Germination, and The Effects of Gut Passage on the Germinability of Seeds: A Meta-Analysis Jason C. Richardson University of South Florida, [email protected] Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the Ecology and Evolutionary Biology Commons Scholar Commons Citation Richardson, Jason C., "The Effects of Gopher Tortoise (Gopherus polyphemus) Herbivory on Plant Community Composition and Seed Germination, and The Effects of Gut Passage on the Germinability of Seeds: A Meta-Analysis" (2018). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/7706 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. The Effects of Gopher Tortoise (Gopherus polyphemus ) Herbivory on Plant Community Composition and Seed Germination, and The Effects of Gut Passage on the Germinability of Seeds: A Meta-Analysis by Jason C. Richardson A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Integrative Biology College of Arts and Sciences University of South Florida Major Professor: Peter Stiling, Ph.D. Marc Lajeunesse, Ph.D. Earl McCoy, Ph.D. Henry Mushinsky, Ph.D. Date of Approval: April 18, 2018 Keywords: herbivory, saurochory, ecology, biodiversity Copyright © 2018, Jason C. Richardson TABLE OF CONTENTS List of Tables ................................................................................................................................. iii List of Figures ................................................................................................................................ iv Abstract .......................................................................................................................................... vi Chapter One: Gopher tortoise herbivory increases plant species richness and diversity ................1 Abstract ................................................................................................................................1 Introduction ..........................................................................................................................2 Methods................................................................................................................................3 Exclosure study site .................................................................................................3 Experimental design.................................................................................................4 Statistical analyses ...................................................................................................5 Results ..................................................................................................................................6 Exclosures ................................................................................................................6 Cafeteria feeding trials .............................................................................................7 Discussion ............................................................................................................................7 Figures................................................................................................................................11 Tables .................................................................................................................................15 References ..........................................................................................................................16 Chapter Two: Gopher tortoise ( Gopherus polyphemus ) gut passage can alter seed germinability ............................................................................................................................20 Abstract ..............................................................................................................................20 Introduction ........................................................................................................................21 Methods..............................................................................................................................22 Results ................................................................................................................................24 Gut passage ............................................................................................................24 Scat exposure .........................................................................................................24 Interactions .............................................................................................................25 Discussion ..........................................................................................................................25 Figures................................................................................................................................28 Tables .................................................................................................................................30 References ..........................................................................................................................33 Chapter Three: The effects of gut passage on the germinability of seeds: a meta-analysis ..........36 Abstract ..............................................................................................................................36 Introduction ........................................................................................................................37 i Methods..............................................................................................................................39 Data collection and extraction ...............................................................................39 Moderator classification.........................................................................................39 Analyses .................................................................................................................40 Results ................................................................................................................................41 Germination percentage .........................................................................................41 Time to germination ...............................................................................................42 Discussion ..........................................................................................................................43 Factors affecting seed germination ........................................................................43 Animal taxa ................................................................................................43 Animal diet.................................................................................................44 Effect of scat ..............................................................................................45 Pulp removal ..............................................................................................45 Fleshy and dry fruits ..................................................................................45 Plant growth forms .....................................................................................46 Native-introduced comparisons .................................................................46 Methodology ..............................................................................................46 Implications of altered germinability .....................................................................47 Future research .......................................................................................................47 Figures................................................................................................................................49 Tables .................................................................................................................................58 References ..........................................................................................................................59 Appendices .....................................................................................................................................62 Appendix A: Supplementary Materials: Chapter 1 ............................................................63 Supplementary Tables ............................................................................................63 Appendix B: Supplementary Materials: Chapter 3 ............................................................65 Supplementary Tables ............................................................................................65 Appendix C: Institutional Animal Care and Use Committee Approval Letter ..................69 Appendix D: Florida Fish and Wildlife Scientific Collecting Permit................................70 Appendix E: Florida Department of Environmental Protection Non-commercial Research/Collecting
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