Trense Daronja, Hoffmann Ary A, Fischer Klaus
Institute for Integrated Natural Sciences, Zoology University Koblenz-Landau Koblenz Germany.
Pest & Environmental Adaptation Research Group School of Biosciences Bio21 Institute Parkville Vic. Australia.
Ecol Evol. 2021 Sep 28;11(21):14697-14714. doi: 10.1002/ece3.8157. eCollection 2021 Nov.
Understanding factors influencing patterns of genetic diversity and the population genetic structure of species is of particular importance in the current era of global climate change and habitat loss. These factors include the evolutionary history of a species as well as heterogeneity in the environment it occupies, which in turn can change across time. Most studies investigating spatio-temporal genetic patterns have focused on patterns across wide geographic areas rather than local variation, but the latter can nevertheless be important particularly in topographically complex areas. Here, we consider these issues in the Sooty Copper butterfly () from the European Alps, using genome-wide SNPs identified through RADseq. We found strong genetic differentiation within the Alps with four genetic clusters, indicating western, central, and eastern refuges, and a strong reduction of genetic diversity from west to east. This reduction in diversity may suggest that the southwestern refuge was the largest one in comparison to other refuges. Also, the high genetic diversity in the west may result from (a) admixture of different western refuges, (b) more recent demographic changes, or (c) introgression of lowland populations. At small spatial scales, populations were structured by several landscape features and especially by high mountain ridges and large river valleys. We detected 36 outlier loci likely under altitudinal selection, including several loci related to membranes and cellular processes. We suggest that efforts to preserve alpine should focus on the genetically diverse populations in the western Alps, and that the dolomite populations should be treated as genetically distinct management units, since they appear to be currently more threatened than others. This study demonstrates the usefulness of SNP-based approaches for understanding patterns of genetic diversity, gene flow, and selection in a region that is expected to be particularly vulnerable to climate change.
在当前全球气候变化和栖息地丧失的时代，了解影响物种遗传多样性模式和种群遗传结构的因素尤为重要。这些因素包括物种的进化历史以及其所占据环境的异质性，而环境异质性又会随时间变化。大多数研究时空遗传模式的研究都集中在广泛地理区域的模式上，而非局部变异，但后者可能仍然很重要，尤其是在地形复杂的地区。在这里，我们使用通过RADseq鉴定的全基因组单核苷酸多态性（SNP），来研究欧洲阿尔卑斯山的煤烟铜蝶（）的这些问题。我们发现阿尔卑斯山内部存在强烈的遗传分化，有四个遗传簇，表明有西部、中部和东部避难所，并且遗传多样性从西向东大幅降低。这种多样性的降低可能表明，与其他避难所相比，西南避难所是最大的一个。此外，西部的高遗传多样性可能源于（a）不同西部避难所的混合，（b）最近的人口变化，或（c）低地种群的基因渗入。在小空间尺度上，种群由几种景观特征构建，尤其是高山山脊和大型河谷。我们检测到36个可能受到海拔选择的异常位点，包括几个与膜和细胞过程相关的位点。我们建议，保护高山的努力应集中在阿尔卑斯山西部遗传多样的种群上，并且白云石种群应被视为遗传上不同的管理单元，因为它们目前似乎比其他种群受到的威胁更大。这项研究证明了基于SNP的方法对于理解一个预计特别易受气候变化影响的地区的遗传多样性、基因流和选择模式的有用性。
