OOS 10-5
An experimental test of the genomic basis of local adaptation
Although natural selection is a deterministic process, the predictability of local adaptation might be limited because the ecological sources of selection and the genomic basis of adaptive traits can be complex. Here, I will describe work which shows that natural selection can have predictable effects on specific phenotypes and their underlying mutations as well as on genome-wide patterns of evolution. We identified the genetic polymorphisms responsible for adaptive pigmentation traits in wild deer mouse populations and directly estimated the consequences of natural selection on these phenotypes and their underlying mutations using a manipulative field experiment replicated in two divergent habitats. In addition, we characterized the impact of selection on genome evolution by tracking changes in allele frequency at 171,333 genetic loci.
Results/Conclusions
We found that natural selection overwhelmingly and strongly favoured local phenotypes and alleles in both ancestral and derived habitat types. Our results demonstrate that selection can have rapid and pervasive effects on patterns of both gene- and genome-scale variation during local adaptation.