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

山区拥有非凡的生物多样性。环境异质性和冰川循环通常会加速山地物种的物种形成和适应，但这些过程如何影响这些物种的基因组分化在很大程度上是未知的。使用新的染色体水平基因组和种群基因组比较，我们研究了生活在新几内亚热带山区的标志性鸟类 Archbold 园丁鸟 ( Amblyornis papuensis ) 的异域差异和选择。我们的研究结果表明，两组人群居住在东部和西部的中央山脉，被孤立CA11800年前，可能是因为随着气候变暖，这种耐寒鸟类的适宜栖息地减少了。我们的基因组扫描检测到高度不同的基因组区域中的基因在发育过程中过度表达，这可能与观察到的种群间体型差异有关。总体而言，我们的结果表明，中部山脉东部和西部之间的环境差异可能会导致它们之间的适应性差异。