Marine species are often characterized by large geographic ranges encompassing vastly different environments. Exposure to these different habitats can facilitate local adaptation. Little is known about local adaptation in the ocean or how selection against immigration contributes to population structuring. But how populations and species respond to disturbance and climate change will ultimately depend on the presence of adaptive diversity and biocomplexity.
Local adaptation associated with ocean climate is likely common in widely distributed species. Some of the steepest clines in allele frequency occur where the Labrador current and the Gulf Stream meet off eastern North America. Latitudinal clines in allele frequency are increasingly being reported in marine species in the Northwest Atlantic and a picture of widespread climate associated structuring is emerging with ocean temperature as the main driver.
Students and PDFs in the lab are currently working on single species trends in genome wide spatial structure as well as multi-species patterns. We use a combination of RAD-seq, SNP arrays and landscape statistical approaches to identify genomic associations and genes involved. These data are being used to model associations with ocean climate, and predict present and future distribution patterns. Example publications:
Spatial genomic variation in Atlantic salmon
Landscape influences on salmon spatial structure
Thermal adaptation in Atlantic cod