Research Philosophy and Approach
The main goal of my research is to discover how complex biological interactions control the divergence of genes, individuals and populations. During the early part of my career, I concentrated on how phenotypes such as migration or mating behavior affect population genetic structure, and how this population structure in turn affects the evolution of these phenotypes. For example, the amount of genetic variation within and between groups determines the potential for group selection, while the outcome of selection at this level can determine population structure by shaping migration and dispersal rates. Now that genomic and molecular genetic tools are becoming increasingly available for model evolutionary systems, I have expanded my research to include this level of analysis. But my main interest remains the interaction of these different levels. For example, we have discovered that opsin genes in the guppy have undergone recent duplication and diversification, in parallel with the diversification of the genes controlling male coloration. This suggests that not only has sexual selection led to the diversification of these opsin genes, but also that gene duplication may have allowed for strong sexual selection to develop in this group of species. In order to understand the fundamental processes of evolution, and to apply evolutionary genetics to questions in biomedical and conservation genetics, we must understand how these forces interact at all levels of biological organization. To that end, I have chosen to study tractable systems for which there is extensive background knowledge, such as the guppy, or systems with important applied outcomes, such as human immunoglobulin loci.