A beak size locus in Darwin's finches facilitated character displacement during a drought

作者:Lamichhaney Sangeet; Han Fan; Berglund Jonas; Wang Chao; Almen Markus Sallman; Webster Matthew T; Grant B Rosemary; Grant Peter R; Andersson Leif*
来源:Science, 2016, 352(6284): 470-474.
DOI:10.1126/science.aad8786

摘要

Ecological character displacement is a process of morphological divergence that reduces competition for limited resources. We used genomic analysis to investigate the genetic basis of a documented character displacement event in Darwin's finches on Daphne Major in the Galapagos Islands: The medium ground finch diverged from its competitor, the large ground finch, during a severe drought. We discovered a genomic region containing the HMGA2 gene that varies systematically among Darwin's finch species with different beak sizes. Two haplotypes that diverged early in the radiation were involved in the character displacement event: Genotypes associated with large beak size were at a strong selective disadvantage in medium ground finches (selection coefficient s = 0.59). Thus, a major locus has apparently facilitated a rapid ecological diversification in the adaptive radiation of Darwin's finches.

  • 出版日期2016-4-22