The maintenance of polymorphisms in natural populations: genetic and environmental correlates of within-species diversity

点击翻译按钮获取中文摘要

The central goal of my research is to understand the origins of biodiversity - beginning with the causes of diversity within species, and eventually drawing inferences about the mechanisms that drive patterns of diversity among species. I explore interactions between genetic and environmental effects by conducting research on two themes: Parallelism and Plasticity. My research on both of these themes is related to the idea of constraints on diversity. Parallelism may be caused by constraints on the diversity of genes used in replicated instances of adaptive evolution. Plasticity and evolution may be constrained to use the same genetic pathways via a lack of redundancy in genetic pathways. My research on these themes addresses two long-term questions: To what extent is adaptive phenotypic evolution constrained? What genes are involved in plastic vs. fixed genetic differences between phenotypically divergent populations? ******Using methods in ecology and genetics, I study freshwater fishes in Canada to generate novel discoveries regarding the genetic and environmental basis of phenotypic variation. I use wild populations of brook stickleback (Culaea inconstans) to study parallelism. Brook stickleback represent one of three stickleback genera (Culaea, Pungitius, and Gasterosteus) that share a parallel pattern of morphological evolution: in each genus, freshwater populations have evolved the reduction or complete loss of pelvic structures (i.e., pelvic girdles and spines). The mechanism underlying this phenotypic parallelism is unknown. My research uses polymorphic populations of brook stickleback in Alberta to address a specific short-term question: to what extent does pelvic reduction evolve via parallel genetic mechanisms among populations of stickleback?******Hybrid fish in the genus Chrosomus have been the focus of my research program for over a decade. Hybrid Chrosomus are endlessly fascinating simply due to their unusual mode of reproduction they are sperm-dependent asexual fish and they serve as a system with which to study genetic and gene expression variation between phenotypically divergent populations. My research uses hybrid Chrosomus populations to address a specific short-term question: what genomic and gene expression differences influence phenotypic differences between hybrid Chrosomus populations?******In addition to generating novel insights into the origins of biodiversity, my research program is aimed at providing unparalleled training for undergraduate students. My undergraduate students will be trained in fieldwork, molecular lab techniques, and data analysis, with the goal of success in professional or graduate schools in Canada and abroad. In particular, my students will gain in-depth hands-on experience with bioinformatics analyses, which will set them up for success in a wide variety of biological disciplines.