Data from: Genomic variation, population history and within-archipelago adaptation between island bird populations

Oceanic island archipelagos provide excellent models to understand
evolutionary processes. Colonisation events and gene flow can interact
with selection to shape genetic variation at different spatial scales.
Landscape-scale variation in biotic and abiotic factors may drive
fine-scale selection within islands, while long-term evolutionary
processes may drive divergence between distantly related populations.
Here, we examine patterns of population history and selection between
recently diverged populations of the Berthelot’s pipit (Anthus
berthelotii), a passerine endemic to three North Atlantic archipelagos.
First we use demographic trees and f3 statistics to show that genome-wide
divergence across the species range is largely shaped by colonisation and
bottlenecks, with evidence of very weak gene flow between
populations. Then, using a genome scan approach, we identify signatures of
divergent selection within-archipelagos at SNPs in genes potentially
associated with craniofacial development and DNA repair. We did
not detect within-archipelago selection at the same SNPs as were detected
previously at broader spatial scales between archipelagos, but did
identify signatures of selection at loci associated with similar
biological functions. These findings suggest that similar ecological
factors may repeatedly drive selection between recently separated
populations, as well as at broad spatial scales across varied
landscapes.