The making of a successful male: an integrated study of male reproductive success in a pest insect.

Male reproductive success is comprised of pre- and post-mating components that have, however, rarely been the subject of integrated study or tested for direct interactions with the environment. This studentship will address this gap in our knowledge, by applying pure and applied research approaches to a pest of significant economic importance, for which transgenic insect technology is well advanced and therefore genetic reagents available. We have applied established experimental evolution protocols to the Mediterranean fruit fly (medfly) and seek here to assay reproductive fitness and determine divergence in male reproductive traits. Our first prediction to be tested is that males evolving under increased sexual competition will evolve more effective courtship and significantly higher post-mating competitiveness (Objectives 1 and 2). This will reveal, under conditions relevant to the natural environment, the traits that make a successful male medfly, and also whether pre- or post-mating traits are more strongly selected under experimental evolution. The student will pursue this work at a novel molecular level by utilising the world-class expertise of the CASE partner to conduct a targeted transcriptional analysis of important male reproductive proteins in the evolved lines (Objective 2). The second main aim is to take this into the applied domain, and test for the first time whether pre- and post-mating traits in evolved lines and in transgenics produced for a novel method of insect control, vary predictably in their response to the key environmental variable of nutritional status (Objective 3). The results will reveal potential trade-offs between male reproductive success and adaptation to experimental evolution or the integration of trangenes for control, and hence show the likely efficacy of the control strains under varying conditions. Overall, the project aims to take a broad approach to integrate the understanding of fundamental, evolutionarily-important traits to applied aspects of insect pest control. The project will apply research expertise in which NERC has invested heavily, namely the study of the dynamics of animal (and especially insect) mating systems, which serve as excellent models for understanding how evolution works. This studentship will therefore apply a considerable body of theory, skills and techniques from such work, but take the research into a novel, applied research area. The project offers a strong and defined training base across a broad range of important skills, and a unique opportunity to capitalise on the synergy between the academic and industrial partners. It should therefore provide a particularly effective springboard for the career progression of the student involved, while generating research of direct relevance to applied end-users. The project fits squarely into NERC priority areas for terrestrial research into evolution and the environment via the exploitation of genome and post-genome science.