Analysis of Host-Parasite Cospeciation: Effects of Spatial and Temporal Scale

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Analysis of Host-Parasite Cospeciation: Effects of Spatial and Temporal Scale Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1996 Analysis of Host-Parasite Cospeciation: Effects of Spatial and Temporal Scale. James W. Demastes Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Demastes, James W., "Analysis of Host-Parasite Cospeciation: Effects of Spatial and Temporal Scale." (1996). LSU Historical Dissertations and Theses. 6331. https://digitalcommons.lsu.edu/gradschool_disstheses/6331 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. 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 face, while others may be from any type o f computer printer. The quality of this reproduction 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 affect 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 left-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 Information Company 300 North Zeeb Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/521-0600 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ANALYSIS OF HOST-PARASITE COSPECIATION: EFFECTS OF SPATIAL AND TEMPORAL SCALE A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Zoology and Physiology by James W. Demastes B.S., A uburn University, 1982 M.S., Louisiana State University, 1990 December 1996 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 9720345 UMI Microform 9720345 Copyright 1997, 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 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGMENTS I thank my major professor, Mark Hafner, who for some reason, accepted a student with a C average, an education degree, and absolutely no idea of what science was really about. He has truly been a complete mentor, teaching me everything from how best to dig a hole to the value of a critical mind in science. My committee members, J. Fitzsimons, W. Font, J. Remsen, and D. Prowell, have all contributed in ways above and beyond the minimum duties of a committee member. For assistance in the field, I thank T. Spradling and P. Sudman, both of whom cheerfully worked for hours, digging holes in sunbaked earth under very hot, very windy conditions asking for nothing in return but a cool beverage and a green chili cheeseburger. T. Spradling also provided valuable comments on this manuscript. A great deal of what I have learned about fieldwork, and mammalogy in general, is a direct result of being lucky enough to work with D. Hafner, who invested much time and effort into my education. For assistance with laboratory work, I thank D. Dittmann, S. Nadler, T. Spradling, and P. Sudman. A special thanks goes to P. Dunn and L. Whittingham, who supplied materials and expertise that made the DNA-fingerprinting possible. For my new-found interest in fractal theory, I thank my brother, Bill. My parents, Bill and Ruth Demastes, have contributed greatly to my graduate career through generous financial donations, and especially through their constant encouragement to pursue a higher education. I would never have attempted graduate study, much less made it this far, ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without the help of Sherry Southerland. She told me I could do it, and I believed her. Financial support for this research was provided by the American Society of Mammalogists, Sigma Xi, The American Museum of Natural History, LSU Museum of Natural Science, and NSF-Louisiana Education Quality Support Fund grant ADP-02. in Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ACKNOWLEDGMENTS.................................................................................... ii LIST OF TABLES................................................................................................. v i LIST OF FIGURES..............................................................................................v ii ABSTRACT........................................................................................................... ix CHAPTER 1 INTRODUCTION............................................................................. 1 2 COSPECIATION OF POCKET GOPHERS (GEOMYS) AND THEIR CHEWING LICE (GEOMYDOECUS)............................. 8 Materials and Methods........................................................ 12 Results and Discussion........................................................ 18 3 A TEST OF THE MATERNAL TRANSMISSION HYPOTHESIS..................................................................................29 Materials and Methods........................................................32 Results and Discussion........................................................ 35 4 POCKET GOPHER DEMOGRAPHY AND LOUSE TRANSMISSION ON A MICROSPATIAL SCALE............... 44 Materials and Methods........................................................46 R esu lts.....................................................................................57 D iscussion...............................................................................66 5 A FRACTAL VIEW OF COSPECIATION ................................ 73 LITERATURE CITED..........................................................................................84 APPENDIXES A Band-sharing coefficients (S) for pocket gophers (below diagonal) and louse population similarities (above diagonal) for Group 1 .......................................................95 B Band-sharing coefficients (S) for pocket gophers (below diagonal) and louse population similarities (above diagonal) for Group 2 .......................................................96 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. C Band-sharing coefficients (S) for pocket gophers (below diagonal) and louse population similarities (above diagonal) for Group 3 .......................................................97 D Band-sharing coefficients (S) for pocket gophers (below diagonal) and louse population similarities (above diagonal) for Group 4 .......................................................98 E Band-sharing coefficients (S) for pocket gophers (below diagonal) and louse population similarities (above diagonal) for Group 5 ....................................................... 99 F Band-sharing coefficients (S) for pocket gophers (below diagonal) and louse population similarities (above diagonal) for Group 6 ..................................................... 100 G Band-sharing coefficients (S) for pocket gophers (below diagonal) and louse population similarities (above diagonal) for Group 7 ..................................................... 101 VITA ........................................................................................................... 102 v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES 2.1. Allelic variation at 24 polymorphic lod in 10 populations of Geomvs and the outgroup, Thomomvs bottae. .......................... 19 2.2. Allelic variation at seven polymorphic lod in the chewing lice, 21 3.1. Length estimates for fragments of each Thomomvs spedmen exam ined .......................................................................................... 36 3.2. Eleven mtDNA restriction-fragment patterns revealed in a survey of pocket gophers, Thomomvs bottae and the outgroup, T. umbrinus.................................................................. 38 4.1. Sex and age composition of 12 louse populations hosted by pocket gophers, Thomomvs bottae.............................................
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