Parallel Geographic Variation in Drosophila melanogaster. Drosophila melanogaster

Here we present an analysis of latitudinal genomic variation in Drosophila melanogaster occurring in parallel in North America and Australia. We find evidence of substantial, shared selection responses on the two continents, probably resulting from selection on standing ancestral variation. Parallel latitudinal differentiation is observed even for variants that are not particularly strongly differentiated, which suggests that very large numbers of polymorphisms are targets of spatially varying selection in this species.