Evolution of High Latitude Birds

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The evolution of high latitude species is linked to both historical and contemporary environmental changes. One way to understand the historical processes influencing species' distribution is through the use of molecular markers, which retain information on historical events in addition to contemporary processes. My research program uses a comparative approach to investigate genetic structure of populations, how behaviour and environment affect population connectivity and ultimately speciation. By examining how landscape features and past climate changes have shaped contemporary populations, we can better understand population dynamics, metapopulation functioning and even predict how they will respond to future climate change. In addition, we can gain further insights into ecological diversification by focusing on closely related sympatric species. My long term research goals focus on the role of landscape features and historical range shifts on population level processes and patterns of population connectivity. Our research has revealed contrasting genetic patterns in some co-distributed species with similar life history patterns and habitat requirements. Some of the patterns correspond to known physical barriers, but others warrant further study to determine the barriers to dispersal. The patterns of population connectivity, dispersal and influence of landscape on genetic structure are better understood as a direct result of our research and have led to a new set of questions. The short term goals of my research program are to study: 1) micro- and macro-geographic population structure in species with mixed migration strategies; 2) intra- and inter-specific contact zones to examine microgeographic landscape genetic; and 3) at-sea behaviour and speciation in seabirds. Major advances in genetic analyses have enabled researchers to answer questions that were not possible even a decade ago. Using GIS technologies and Bayesian analyses, my students and I can create historical range maps for individual species using paleoclimate data and compare these to our genetic data. Combining the newer, more powerful analyses with traditional markers and a larger number of species will allow us to better understand evolutionary processes. Using genetic and genomic tools, we will determine if geographic variation is the result of restricted gene flow or other ecological factors, obtain a more complete and accurate picture of rangewide gene flow and fine scale population genetic structure and gain invaluable insights into the process of speciation. The multifaceted and integrative set of short term projects allows us to study the speciation process. For example, do seabird colonies with behavioural differences also show genetic differences? What is the influence of migratory behaviour on intraspecific gene flow? Specifically, do resident populations have higher levels of population structure than migratory populations of the same species?