Alex CTGenetics of adaptation 

My research focuses on the process and outcomes of selection in fishes, testing hypotheses about the genetic basis of adaptation to environmental change. We study the genetic basis of adaptive behaviours, morphology, physiology and examine the imprint of selection on genomes during population divergence and speciation (Rogers and Bernatchez; Rogers and Bernatchez 2007; Renaut et al. 2011; Rogers et al. 2012, Rogers et al. 2013, McEwen et al. 2013). (Figure: A. Pistore CT scan of threespine stickleback, H. Jamniczky)



Understanding the remarkable fits between organisms and their environment is a central objective of our research. Dobzhansky (1951) believed that the genotype of a species is an integrated system adapted to the ecological niche in which a species lives.  Such adaptive divergence is predicted to reduce gene flow and result in the formation of reproductive isolation at genes underlying adaptive phenotypes between populations. We compare genomic patterns of diversity between diverging populations to identify and differentiate patterns of polymorphism among populations that do not conform to expectations of neutral demographic models, and how these genomic regions may contribute to adaptation and speciation in postglacial fishes. (Image: Figure 1 from Rogers et al. 2013).

Molecular ecology and conservation

One of our main research interests is understanding the relative influences of historic and ecological processes that have shaped the present distribution and life histories of species. Historically contingent genetic diversity refers to locally specific selection pressures and stochastic effects that may have influenced isolated assemblages in the past. The role of historical contingency in Canada, due in large part to isolation of species in glacial refugia during the last ice age, has been shown to have a significant role in the evolution of reproductive isolation in several species, especially in postglacial populations of fishes.  (Image: Distribution of five glacial races of lake whitefish in Canada in relation to historic ice age refugia, Mee et al. 2015)