Loma Linda University TheScholarsRepository@LLU: Digital Archive of Research, Scholarship & Creative Works Loma Linda University Electronic Theses, Dissertations & Projects 6-2018 The esiD gn of Complex Weapons Systems in Scorpions: Sexual, Ontogenetic, and Interspecific Variation Gerard A. A. Fox Follow this and additional works at: http://scholarsrepository.llu.edu/etd Part of the Animal Sciences Commons, Biology Commons, and the Medicine and Health Sciences Commons Recommended Citation Fox, Gerard A. A., "The eD sign of Complex Weapons Systems in Scorpions: Sexual, Ontogenetic, and Interspecific aV riation" (2018). Loma Linda University Electronic Theses, Dissertations & Projects. 516. http://scholarsrepository.llu.edu/etd/516 This Dissertation is brought to you for free and open access by TheScholarsRepository@LLU: Digital Archive of Research, Scholarship & Creative Works. It has been accepted for inclusion in Loma Linda University Electronic Theses, Dissertations & Projects by an authorized administrator of TheScholarsRepository@LLU: Digital Archive of Research, Scholarship & Creative Works. For more information, please contact [email protected]. LOMA LINDA UNIVERSITY School of Medicine in conjunction with the Faculty of Graduate Studies ____________________ The Design of Complex Weapons Systems in Scorpions: Sexual, Ontogenetic, and Interspecific Variation by Gerad A. A. Fox ____________________ A Dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Biology ____________________ June 2018 © 2018 Gerad A. A. Fox All Rights Reserved Each person whose signature appears below certifies that this dissertation in his/her opinion is adequate, in scope and quality, as a dissertation for the degree Doctor of Philosophy. , Chairperson William K. Hayes, Professor of Biology Leonard R. Brand, Professor of Biology and Geology Penelope J. Duerksen-Hughes, Professor of Biochemistry Stephen G. Dunbar, Professor of Biology Zia Nisani, Professor of Biology, Antelope Valley College iii ACKNOWLEDGEMENTS Those who know me understand that I am not much for most emotional-based responses; however this accomplishment would not have been possible without the help, support, and understanding of many people, and that should be acknowledged. It has been a long process to get to this point and without the encouragement of those around me I know that I would not have succeeded. To my parents, who sacrificed that I might make it here, I owe the most. My appreciation for the natural world was instilled from my father, Geoffrey, whom I wish had been well enough to visit me here to see some of what I was doing, or at least seen me finish, but I took too long. My mother, Geneva, has been an unending source of encouragement and aid, without whom I would never have had the will or ability to complete this journey. For the rest of my family there are too many to mention all here but I likewise thank them for their interest, encouragement and understanding. During my time as a grad student I was taken in by Hilbert Lentz and Elsie Mclellan, a wonderful couple who treated me like family, giving me a place to go, support throughout this experience, and letting my little Miss stay there when she could not be with me in the lab. Bert’s quiet support and Elsie’s enthusiasm for everything I did (even coming with me to collect scorpions on occasion) were ever present. I am very thankful to the EBS department as a whole for their kindness and willingness to support me during my time here, and had done so much to help me to succeed. Further, I wish to thank my committee for their support: Dr. Zia Nisani without whom I would likely not have worked with scorpions in the first place; Dr. Leonard Brand, for his insistence on considering alternate hypotheses; Dr. Stephen Dunbar, for his iv interest and encouragement to continue on; and Dr. Penelope Duerksen-Hughes, for her thought-provoking questions. I especially want thank Dr. William Hayes for his indomitable enthusiasm, patience, encouragement, and friendship. He guided someone who had an active dislike for statistical models to put together a dissertation almost fully dependent upon them, so that now there is at least an uneasy alliance. I also wish to thank my lab mates for their comradery and willingness to brainstorm ideas and occasionally venture into the desert on hot, dry nights collecting fluorescent treasures. v CONTENT Approval Page .................................................................................................................... iii Acknowledgements ............................................................................................................ iv List of Figures .................................................................................................................... xi List of Tables .................................................................................................................... xii List of Abbreviations ....................................................................................................... xiv Abstract ............................................................................................................................ xvi Chapter 1. Introduction ..............................................................................................................1 Identifying Sexual Dimorphism .........................................................................3 Examining the Venom Delivery System............................................................5 Examining Weapons Design in Two Sister Scorpion Species...........................7 Novel Insights ....................................................................................................9 References ........................................................................................................10 2. The Dilema of Choosing a Reference Character for Measureing Sexual Size Dimorphism, Sexual Body Component Dimorphism, and Character Scaling: Cryptic Dimorphism and Allometry in the Scorpion Hadrurus arizonensis .............................................................................................................15 Abstract ............................................................................................................16 Introduction ......................................................................................................17 Materials and Methods .....................................................................................22 Ethics Statement.........................................................................................22 Scorpions....................................................................................................23 Morphological Measurements ...................................................................23 Statistics .....................................................................................................24 Results ..............................................................................................................27 Discussion ........................................................................................................41 General Pattern of Dimorphism .................................................................41 Choice of Reference Character and its Implications ..................................42 Sexual Size Dimorphism (SSD).................................................................44 vi Sexual Body Component Dimorphism (SBCD), Allomety and Potential Selection .....................................................................................46 Conclusions ................................................................................................50 References ........................................................................................................53 3. Venom Yield in Scorpions: A Review of Methods, Yields, and Potential Sources of Variation ..............................................................................................83 Abstract ............................................................................................................84 Introduction ......................................................................................................85 Methods of Venom Extraction .........................................................................87 Taxonomic Coverage .......................................................................................88 Nature of Study ................................................................................................88 Factors Associated with Venom Yield ............................................................89 Phylogenetic Variation...............................................................................90 Geographic Variation .................................................................................91 Sexual Variation.........................................................................................92 Body Size ...................................................................................................93 Seasonal Variation .....................................................................................93 Circadian Variation ....................................................................................94 Dietary Influence .......................................................................................95 Single vs Repeated Extration .....................................................................96