Divergence with gene flow within the recent chipmunk radiation (Tamias)
Divergence with gene flow within the recent chipmunk radiation (Tamias)
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DOI：
10.1038/hdy.2014.27
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发表时间：
2014-04
期刊：
影响因子：
3.8
通讯作者：
J. Sullivan;J. Demboski;K. Bell;S. Hird;B. Sarver;N. Reid;J. Good
中科院分区：
文献类型：
--
作者：
J. Sullivan;J. Demboski;K. Bell;S. Hird;B. Sarver;N. Reid;J. Good
越来越多的数据支持了基因流趋异（DGF）在生物多样性产生中的重要性。在这种情况下，谱系分化发生在一个较短的时间尺度比生殖隔离的完成。虽然探索驱动分化和通过杂交防止同质化的机制是至关重要的，但记录自然界中的DGF病例同样重要。在这里，我们综合了过去十几年来在花栗鼠（Tamias）辐射DGF上积累的数据，并结合了新的数据，这些数据量化了T.产于落基山脉中部和南部的四条带组。这些新数据（188个细胞色素B序列）使序列总数达到1871个;我们测序的大约16%（298）的金花鼠表现出渗入的mtDNA。这包括亚种之间以及近亲和远亲类群之间正在进行的基因渗入。此外，我们已经确定了几个分类群，显然是固定的古老的基因渗入，其中没有证据表明正在进行的基因渗入。一个经常性的观察是，这些基因渗入发生在生态和形态分歧，有时非姐妹类群，从事有据可查的生态位分区。因此，在北美西部的花栗鼠辐射代表了一个很好的哺乳动物物种形成的例子，在面对经常性的基因流之间的血统，并在地理，栖息地分化和交配系统的生态和性选择的重要作用。
Increasing data have supported the importance of divergence with gene flow (DGF) in the generation of biological diversity. In such cases, lineage divergence occurs on a shorter timescale than does the completion of reproductive isolation. Although it is critical to explore the mechanisms driving divergence and preventing homogenization by hybridization, it is equally important to document cases of DGF in nature. Here we synthesize data that have accumulated over the last dozen or so years on DGF in the chipmunk (Tamias) radiation with new data that quantify very high rates of mitochondrial DNA (mtDNA) introgression among para-and sympatric species in the T. quadrivittatus group in the central and southern Rocky Mountains. These new data (188 cytochrome b sequences) bring the total number of sequences up to 1871; roughly 16%(298) of the chipmunks we have sequenced exhibit introgressed mtDNA. This includes ongoing introgression between subspecies and between both closely related and distantly related taxa. In addition, we have identified several taxa that are apparently fixed for ancient introgressions and in which there is no evidence of ongoing introgression. A recurrent observation is that these introgressions occur between ecologically and morphologically diverged, sometimes non-sister taxa that engage in well-documented niche partitioning. Thus, the chipmunk radiation in western North America represents an excellent mammalian example of speciation in the face of recurrent gene flow among lineages and where biogeography, habitat differentiation and mating systems suggest important roles for both ecological and sexual selection.