Department of Medical Biochemistry and Microbiology, Uppsala University, SE-751 23 Uppsala, Sweden.
Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden.
Nature. 2015 Feb 19;518(7539):371-5. doi: 10.1038/nature14181. Epub 2015 Feb 11.
Darwin's finches, inhabiting the Galápagos archipelago and Cocos Island, constitute an iconic model for studies of speciation and adaptive evolution. Here we report the results of whole-genome re-sequencing of 120 individuals representing all of the Darwin's finch species and two close relatives. Phylogenetic analysis reveals important discrepancies with the phenotype-based taxonomy. We find extensive evidence for interspecific gene flow throughout the radiation. Hybridization has given rise to species of mixed ancestry. A 240 kilobase haplotype encompassing the ALX1 gene that encodes a transcription factor affecting craniofacial development is strongly associated with beak shape diversity across Darwin's finch species as well as within the medium ground finch (Geospiza fortis), a species that has undergone rapid evolution of beak shape in response to environmental changes. The ALX1 haplotype has contributed to diversification of beak shapes among the Darwin's finches and, thereby, to an expanded utilization of food resources.
达尔文雀，栖息于加拉帕戈斯群岛和可可斯岛，是物种形成和适应性进化研究的标志性模式生物。在此，我们报告了对 120 只个体的全基因组重测序结果，这些个体代表了所有的达尔文雀物种和两个近亲。系统发育分析显示与基于表型的分类法存在重要差异。我们在整个辐射过程中发现了广泛的种间基因流证据。杂交产生了具有混合血统的物种。一个包含编码影响颅面发育的转录因子的 ALX1 基因的 240 千碱基对单倍型，与达尔文雀物种以及经历了快速喙形进化以适应环境变化的中型地雀（Geospiza fortis）的喙形多样性强烈相关。ALX1 单倍型促进了达尔文雀的喙形多样化，从而扩大了对食物资源的利用。
