Laboratory of Aquatic Ecology, Evolution and Conservation, University of Leuven, Leuven, Belgium.
J Evol Biol. 2014 Apr;27(4):748-59. doi: 10.1111/jeb.12347. Epub 2014 Mar 3.
Although genetic diversity provides the basic substrate for evolution, there are a limited number of studies that assess the impact of recent climate change on intraspecific genetic variation. This study aims to unravel the degree to which historical and contemporary factors shape genetic diversity and structure across a large part of the range of the range-expanding damselfly Coenagrion scitulum (Rambur, 1842). A total of 525 individuals from 31 populations were genotyped at nine microsatellites, and a subset was sequenced at two mitochondrial genes. We inferred the importance of geography, environmental factors, and recent range expansion on genetic diversity and structure. Genetic diversity decreased going westwards, suggesting a signature of historical post-glacial expansion from east to west and the presence of eastern refugia. Although genetic differentiation decreased going northwards, it increased in the northern edge populations, suggesting a role of contemporary range expansion on the genetic make-up of populations. The phylogeographical context was proven to be essential in understanding and identifying the genetic signatures of local contemporary processes. Within this framework, our results highlight that recent range expansion of a good disperser can decrease genetic diversity and increase genetic differentiation which should be considered when devising suitable conservation strategies.
尽管遗传多样性为进化提供了基本的基础，但评估近期气候变化对种内遗传变异影响的研究数量有限。本研究旨在揭示历史和当代因素在多大程度上塑造了扩展范围的蜻蜓 Coenagrion scitulum（Rambur，1842）大范围的遗传多样性和结构。从 31 个种群中采集了 525 个个体的 9 个微卫星基因座进行基因分型，并对其中一部分进行了两个线粒体基因的测序。我们推断了地理、环境因素和近期的范围扩展对遗传多样性和结构的重要性。遗传多样性向西减少，这表明存在历史上的冰川后从东向西扩张的特征和东部避难所。虽然向北的遗传分化减少，但在北部边缘种群中增加，这表明近期的范围扩展对种群的遗传组成起着作用。系统发生地理背景对于理解和识别当地当代过程的遗传特征至关重要。在这个框架内，我们的结果强调了良好扩散者的近期范围扩展会降低遗传多样性并增加遗传分化，这在制定合适的保护策略时应加以考虑。
