Assistant Professor, Ecology, Evolution, and Behavior, University of Minnesota

Statement.  Over long timescales, biological diversity is shaped by trait evolution within populations and by the speciation and extinction of lineages.  My research focuses on geographic ranges and plant mating systems as two examples of characters influenced by both these microevolutionary and macroevolutionary forces.

Questions include: How do regional differences in rates of speciation, extinction, and range shifts determine geographic variation in species richness?  How are range limits affected by interspecific interactions, dispersal, and local adaptation?  How does species selection shape the diversity of plant reproductive systems?  How does breeding system affect the establishment and evolution of polyploid species?

I address these topics through the development and application of mathematical models, usually in collaboration with experts in various empirical systems.  On the macroevolutionary side, I work with phylogenetic models of lineage diversification and trait evolution.  I am especially interested in how phylogenetic analyses can be extended to incorporate additional processes and lines of evidence, and for which questions this is essential.  For microevolutionary questions, I work with spatial models of resource competition, hybridization, dispersal, and the evolution of quantitative traits.