How do new species arise, what makes them variable, and how to go about conserving them for the future? We’ve come a long way in our understanding of the evolution of life in the 150 years since the publication of the Origin of the Species, especially given the wave of new molecular tools and theory, which has given the field of evolutionary biology new life and rigour.  My research in Dr. Darren Irwin’s lab involves using natural experiments, such as the recolonization of the forests of North America by songbirds following the retreat of the glaciers, to better understand the evolution of local adaptation and reproductive isolation. Using areas of secondary contact where divergent populations now meet we can 1) observe a wide spectrum reproductive barriers in taxa that are strongly reproductively isolated (i.e. the winter wren and pacific wren) to taxa that hybridize extensively (i.e. Townsend’s and black-throated green warblers) and 2) test for evidence of introgression in genes or traits that may have been favoured by selection. I am using genetic, physiological, behavioural, and ecological methods to understand how these critters have adapted to their different lives apart and the evolutionary dynamics and consequences now that they are back together.