Contemporary Population Structure and Genomic Signals of Natural Selection in Pink Salmon

An important goal in biology is to understand the role that genetic variation plays in local adaptation. By attempting to identify genes under selection, we can begin to understand which genes are ecologically important to a population in a particular environment. Pink salmon are an ideal resource to explore natural selection in wild populations. The species is wide-ranging, and its strict life history leads to two lineages that use the same habitat sequentially, separated in time.  We used genotyping by sequencing to survey thousands of RAD loci in four pairs of pink salmon populations from Asia and compared those data to previously collected data from three pairs of populations from North America.  Using the two datasets, we examined the contemporary population structure of the Asian and North American pink salmon throughout the range. We also investigated genomic signals of parallel natural selection in the lineages of pink salmon sharing river habitat, replicated on both continents.