How is the conflict between selection and gene flow resolved during the evolution of barriers to reproduction? Reinforcement, the evolution of reproductive isolation between sympatric taxa in response to selection against hybridization, is an ideal arena in which to study the evolutionary forces of selection and gene flow during the process of speciation. Extensive research has focused on identifying examples of reinforcement across the tree of life, and theoretical research has characterized the evolutionary conditions suitable for reinforcement to occur. Yet, little is known about the strength, mechanisms, and sources of selection, or the direction, amount, and timing of gene flow during reinforcement. Our research on flower color divergence in Phlox drummondii aims to characterize the evolutionary processes involved in reinforcement in order to understand when and why reproductive isolation can evolve with gene flow. Our work combines phenotypic quantifications of reproductive isolating barriers, with genomic estimates of gene flow between sympatric taxa, and genetic investigations of loci causing reinforcement.
Administrative contact - Michelle Lee