The Ecology of Sexual Selection

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Measuring sexual selection in nature is a major focus of evolutionary biology and has been facilitated by the development of multivariate statistical tools. However, the future of these tools lies in bringing them within an experimental framework. My long-term research objective is to understand how the environment affects the evolution of mating systems in the wild. A major difficulty is collecting accurate measures of fitness for large numbers of individuals. One solution is to use systems in which individual fitness is recorded on the organism's body. Such is the case for male mating success in insects of the genus Cyphoderris, where mating females chew on the male's hind wings, damaging them permanently. I will use the Cyphoderris system to pursue 2 short-term research objectives.******Short-Term Objective 1: The Effects of Ecological Gradients on Sexual Selection***Comparatively little attention has been focussed on the evolutionary effects of ecological changes on wild populations. I have shown that hungry female Cyphoderris are more likely to mate than well-fed females. This raises the possibility that the strength of sexual selection is dependent upon resource availability. Cyphoderris populations are found throughout the forested interior of BC and western regions of Alberta areas that are both ecologically and economically important. I will measure sexual selection in wild populations of Cyphoderris in these regions that have been exposed to varying degrees of environmental disturbance (e.g. forest harvest regime, pine beetle infestation, fire occurrence). Evolutionary adaptations are important to our understanding of the scope and long-term effects of ecological disturbances and the ability of wild populations to tolerate environmental change.******Short-Term Objective 2: The Ecology of Hybridization and the Breakdown of Species Isolating Mechanisms***Hybrid zones have long fascinated evolutionary biologists because they are natural laboratories in which the processes governing speciation and the maintenance of species boundaries can be tested. Recently, I have found morphological evidence of hybridization between C. buckelli and C. monstrosa, and have shown that males provide nutritional resources to females during mating. I propose to use the Cyphoderris hybrid zone to study the evolutionary effects of species isolating mechanisms. Understanding evolution in hybrid zones is important as humans alter the ranges of wild populations.******Humans continue to modify the environment at an unprecedented rate. Most work has concentrated on understanding and mitigating our effects on biodiversity. However, it is clear that evolution can occur over ecological timescales meaning that conservation must consider evolutionary effects of ecological change. My proposed research will address this important gap in our understanding of the effects of anthropogenic change.