Sexual selection and sex allocation in the gregarious parasitoid wasp Nasonia vitripennis

Parasitic wasps;Sexual selection in animals;Sex allocation;Hymenoptera

Moynihan, Anna Margaret ; Shuker, David M. ; Shuker, David M.

University:University of St Andrews

Department:Biology (School of)

关键词: Parasitic wasps;    Sexual selection in animals;    Sex allocation;    Hymenoptera;   

Others  :  https://research-repository.st-andrews.ac.uk/bitstream/handle/10023/3129/AnnaMoynihanPhDThesis.pdf?sequence=3&isAllowed=y

来源: DR-NTU

【 摘 要 】

Sex allocation and sexual selection have been heavily studied, but rarely linked. Inthis thesis I investigated the interface between them in the gregarious parasitoid waspNasonia vitripennis, both directly and through their interactions with the matingsystem and sexual conflict. Chapter 2 investigated sexual selection and mating at thenatal site: earlier eclosing males mated more females independently of body size.Nasonia follows Local Mate Competition, which describes how a female laying eggsalone on a patch of resources (a so-called single-foundress) should lay an extremelyfemale-biased brood to minimise competition between her sons, yet ensure all herdaughters are fertilised. Based on this I predicted that males with with fewer brotherswould be better inseminators. Despite finding significant among-strain variation in(1) single-foundress sex ratio, (2) mate competitiveness when alone and (3) when incompetition, (4) sperm resources, but not (5) sperm-depletion (Chapters 3 & 4), I didnot find the predicted relationship. Conversely males from strains with more brothershad a higher mating success under competition (Chapter 3) leading to the question:does mating success select on sex ratio or vice versa? Either way it is a result of aninteraction between sexual selection and sex allocation. Chapter 5 investigated therole of male post-copulatory courtship on female re-mating, and found that among-strain variation in female re-mating was not associated with variation in the durationof the post-copulatory courtship. Chapter 6 reviewed sexual conflict in theHymenoptera: their haplodiploid genetics, newly sequenced genomes and varied life-histories provides a base for future research to build on. Finally I highlight the novellinks between sexual selection, sex allocation, sexual conflict and the mating systemfound during my studies that will hopefully prompt future research on this topic.