Genomic signatures of rapid adaptive divergence in a tropical montane species

Mountain regions contain extraordinary biodiversity. The environmental heterogeneity and glacial cycles often accelerate speciation and adaptation ofmontane species, but how these processes influence the genomic differentiation of these species is largely unknown. Using a novel chromosomelevel genome and population genomic comparisons, we study allopatricdivergence and selection in an iconic bird living in a tropical mountainregion in New Guinea, Archbold’s bowerbird (Amblyornis papuensis). Ourresults show that the two populations inhabiting the eastern and western Central Range became isolated ca 11 800 years ago, probably because the suitablehabitats for this cold-tolerating bird decreased when the climate got warmer.Our genomic scans detect that genes in highly divergent genomic regions areover-represented in developmental processes, which is probably associatedwith the observed differences in body size between the populations. Overall,our results suggest that environmental differences between the eastern andwestern Central Range probably drive adaptive divergence between them