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Hemideina Crassidens UNIVERSITÉ DU QUÉBEC À MONTRÉAL LE MAINTIEN DE STRATÉGIES ALTERNATIVES CHEZ LE WELLINGTON TREE WETA (HEM/DE/NA CRASSIDENS): TESTER LES PRÉDICTIONS DE L'HYPOTHÈSE DE POLYMORPHISME GÉNÉTIQUE MÉMOIRE PRÉSENTÉ COMME EXIGENCE PARTIELLE DE LA MAÎTRISE EN BIOLOGIE PAR SARAHNASON JANVIER 2019 UNIVERSITÉ DU QUÉBEC À MONTRÉAL Service des bibliothèques Avertissement La diffusion de ce mémoire se fait dans le respect des droits de son auteur, qui a signé le formulaire Autorisation de reproduire et de diffuser un travail de recherche de cycles supérieurs (SDU-522 - Rév.07-2011). Cette autorisation stipule que «conformément à l'article 11 du Règlement no 8 des études de cycles supérieurs, [l'auteur] concède à l'Université du Québec à Montréal une licence non exclusiye d'utilisation et de publication de la totalité ou d'une partie importante de [son] travail de recherche pour des fins pédagogiques et non commerciales. Plus précisément, [l'auteur] autorise l'Université du Québec à Montréal à reproduire, diffuser, prêter, distribuer ou vendre des copies de [son] travail de recherche à des fins non commerciales sur quelque support que ce soit, y compris l'Internet. Cette licence et cette autorisation n'entraînent pas une renonciation de [la] part [de l'auteur] à [ses] droits moraux ni à [ses] droits de propriété intellectuelle. Sauf entente contraire, [l'auteur] conserve la liberté de diffuser et de commercialiser ou non ce travail dont [il] possède un exemplaire.» UNIVERSITÉ DU QUÉBEC À MONTRÉAL THE MAINTENANCE OF ALTERNATIVE STRATEGIES IN WELLINGTON TREE WETA (HEMIDEINA CRASSJDENS): TESTING THE PREDICTIONS OF THE GENETIC POLYMORPHISM HYPOTHESIS MÉMOIRE PRESENTED IN FULFILLMENT OF MASTER'S IN BIOLOGY BY SARAHNASON JANUARY, 2019 REMERCIEMENTS 1 would like to thank my supervisor Dr. Clint Kelly for his support and mentorship throughout my degree. This project required a lot of problem-solving and presented plenty of obstacles to overcome, and 1 am so glad that 1 had someone on my side throughout! Thank you for helping me to take my first steps into research and a scientific career. Y our mentorship and advice have made me a better scientist and a stronger person. 1 have had so many incredible mentors to help me through this degree. 1 would like to thank Dr. Arne Mooers, Dr. Alison Derry, Dr. Jessica Haines, Dr. Tina Wey, Dr. Joshua Miller, Dr. Axel Moehrenschlager and Dr. Catherine Cullingham for their invaluable mentorship and support. These people are such superstars for taking time out of their schedules to help young scientists such as myself, not because they have any obligation to, but because they care. Their emotional support and career advice have meant the world to me and 1 look up to them as examples of who 1 would like to become as a scientist. 1 would also like to thank Dr. Alison Derry and Dr. Rowan Barrett for their insights and comments on my proposal, which were so helpful in expanding my perspectives on this project. It was such a delight to exchange thoughts and ideas during my proposal defense and 1 was so grateful for the excitement and thoughtfulness that you both brought to the process. 1 thank also Dr. Emma Despland and Dr. Grant Brown for their comments on this thesis. The final product is stronger because ofyou! 1 have been lucky to be a part of so many great teams for this project. 1 am so grateful to Dr. David Coltman for welcoming me into his lab at the University of Alberta to complete the genetic work for this study, to Dr. Corey Davis for his time and patience in training me, and to Anh Dao for - well - everything else when it cornes to labwork iii (and for telling me to go home sometimes!). At the end of my degree I also had the joy of completing an intemship with Dr. Axel Moehrenschlager at the Calgary Zoo, where I am so thankful to have spent time. The warm, welcoming Conservation team and the positive working environment played no small role in helping me to finish this thesis. 1 would particularly like to thank Dr. Typhenn Brichieri-Colombi for her support when 1felt1 might not make it past the finish line! To my labmates at UQAM, Aurélie Lagueux-Beloin, Valérie L'Heureux, Éloïse Adam-Granger and Julien Céré: thank you so much for helping an anglophone humble along and make things work. Y our support in helping me navigate outside of my native language and make a home for myself in Québec was so important and so appreciated. To the MSc ladies: we made it! Completing this thesis would have been much more stressful and less fun without your support and friendship. Finally, my rocks at home: my roommates and friends in Montréal, Charlotte Forss, Shrinkhala Dawadi and Samantha Kinley - thank you for being there for me and never failing to lift me up at the end of the day! And Charlotte especially, thank you for a long and dear friendship that I rel y on and cherish (and for feeding me sometimes). 1 thank my dear friends Priya Narine, Lauren LaBossiere, Kurt Y akimovich, and Allison J andura for always lending an ear and helping me to move forward. Lastly, but definitely not leastly, my parents Ted and Cindy: I love you so much. This degree happened because of you. I dedicate this work to you and I hope one day that 1 can give back what you've given me (and I don't just mean the money). I especially thank my mom, because she is the woman scientist hero that everyone needs and an utter inspiration. TABLE OF CONTENTS LIST OF FIGURES ...................................................................................................... vi LIST OF TABLES ..................................................................................................... viii LIST OF SYMBOLS AND UNITS ............................................................................. ix RÉSUMÉ ....................................................................................................................... x INTRODUCTION ......................................................................................................... 1 0.1. Sexual selection and mating strategies .......................................................................... 1 0.1.1. Alternative mating strategies (AMSs) .................................................................... 2 0.1.2. Maintaining AMSs: a review of the hypotheses ..................................................... 4 0.1.3. Insect life histories and their implications for AMSs ............................................. 8 0.1.4. Evolutionary and conservation significance of AMSs ......................................... 10 0.2. Mechanisms underlying equal fitnesses among mating strategies .............................. 12 0.2.1. Sperm competition ................................................................................................ 12 0.2.2. Resource polymorphism and differential niche use ............................................. 15 0.3. Female mate choice .................................................................................................... 17 0.3.1. Benefits ofpolyandry ........................................................................................... 18 0.3.2. Cryptic female choice ........................................................................................... 21 0.4. Study species and field site .......................................................................................... 24 CHAPTER I SUPPORT FOR MAINTENANCE OF ALTERNATIVE MATING STRATEGIES VIA GENETIC POLYMORPHISM IN THE WELLINGTON TREE WETA ......................................................................................................................... 28 1.1. Abstract ........................................................................................................................ 29 1.2. Introduction .................................................................................................................. 30 1.3. Methods ....................................................................................................................... 36 1.3.1. Collection of harems and offspring in the field .................................................... 36 1.3.2. Patemity assignment of wild-caught males .......................................................... 38 1.3.3. Statistical analyses ................................................................................................ 40 1.4. Results .......................................................................................................................... 43 1.4.1. Harem success ...................................................................................................... 43 1.4.2. Patemity assignment ............................................................................................. 44 1.4.3. Male reproductive success and relative fitness .................................................... 45 1.5. Discussion .................................................................................................................... 54 1.5.1. Morph-specific fitness and the genetic polymorphism hypothesis ...................... 54 1.5.2. Harem success among morphs ............................................................................. 58 1.5.3. Rates of multiple mating and fitness benefits ....................................................... 60 1.5.4. Implications of genetic findings ........................................................................... 64 1.5.5. Speciation and conservation implications ...........................................................
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