Rapid range expansion increases genetic differentiation while causing limited reduction in genetic diversity in a damselfly

Many ectothermic species are currently expanding their geographic range due to global warming. This can modify the population genetic diversity and structure of these species because of genetic drift during the colonization of new areas. Although the genetic signatures of historical range expansions have been investigated in an array of species, the genetic consequences of natural, contemporary range expansions have received little attention, with the only studies available focusing on range expansions along a narrow front. We investigate the genetic consequences of a natural range expansion in the Mediterranean damselfly Coenagrion scitulum, which is currently rapidly expanding along a broad front in different directions. We assessed genetic diversity and genetic structure using twelve microsatellite markers in five centrally located populations and five recently established populations at the edge of the geographic distribution. Our results suggest that, although a marginal significan...

受全球变暖影响，当前许多变温物种（ectothermic species）的地理分布范围正持续扩张。在开拓新分布区域的过程中，遗传漂变（genetic drift）会改变这些物种的种群遗传多样性与种群遗传结构。尽管已有一系列物种的历史分布扩张的遗传信号得到了相关研究，但自然发生的当代分布扩张所带来的遗传后果却鲜受关注，现有仅存的研究均聚焦于前沿狭窄的分布扩张事件。本研究以当前正沿多个方向快速进行宽广前沿扩张的地中海蟌（Coenagrion scitulum）为研究对象，探究其自然分布扩张所带来的遗传后果。本研究采用12个微卫星标记（microsatellite markers），对5个中心分布种群与5个分布边界的新近定殖种群的遗传多样性与遗传结构进行了评估。本研究结果表明，尽管存在边际显著……