Bernos Thaïs A, Lajbner Zdenek, Kotlík Petr, Hill Jacklyn M, Marková Silvia, Yick Jonah, Mandrak Nicholas E, Jeffries Ken M
Department of Ecology and Evolutionary Biology University of Toronto Toronto Ontario Canada.
Department of Biological Sciences University of Toronto Scarborough Toronto Ontario Canada.
Evol Appl. 2024 Oct 4;17(10):e70006. doi: 10.1111/eva.70006. eCollection 2024 Oct.
Species invading non-native habitats can cause irreversible environmental damage and economic harm. Yet, how introduced species become widespread invaders remains poorly understood. Adaptation within native-range habitats and rapid adaptation to new environments may both influence invasion success. Here, we examine these hypotheses using 7058 SNPs from 36 native, 40 introduced and 19 farmed populations of tench, a fish native to Eurasia. We examined genetic structure among these populations and accounted for long-term evolutionary history within the native range to assess whether introduced populations exhibited lower genetic diversity than native populations. Subsequent to infer genotype-environment correlations within native-range habitats, we assessed whether adaptation to native environments may have shaped the success of some introduced populations. At the broad scale, two glacial refugia contributed to the ancestry and genomic diversity of tench. However, native, introduced and farmed populations of admixed origin exhibited up to 10-fold more genetic diversity (i.e., observed heterozygosity, expected heterozygosity and allelic richness) compared to populations with predominantly single-source ancestry. The effects of introduction to a new location were also apparent as introduced populations exhibited fewer private alleles (mean = 9.9 and 18.9 private alleles in introduced and native populations, respectively) and higher population-specific compared to native populations, highlighting their distinctiveness relative to the pool of allelic frequencies across tench populations. Finally, introduced populations with varying levels of genetic variation and similar genetic compositions have become established and persisted under strikingly different climatic and ecological conditions. Our results suggest that lack of prior adaptation and low genetic variation may not consistently hinder the success of introduced populations for species with a demonstrated ability to expand their native range.
入侵非本土栖息地的物种会造成不可逆转的环境破坏和经济损害。然而，外来物种如何成为广泛分布的入侵者仍鲜为人知。在本土栖息地内的适应以及对新环境的快速适应都可能影响入侵的成功。在此，我们使用来自欧亚大陆本土的36个种群、引入的40个种群和养殖的19个种群的7058个单核苷酸多态性（SNP）对丁鱥（一种原产于欧亚大陆的鱼类）来检验这些假设。我们研究了这些种群之间的遗传结构，并考虑了本土范围内的长期进化历史，以评估引入种群的遗传多样性是否低于本土种群。在推断本土栖息地内的基因型与环境的相关性之后，我们评估了对本土环境的适应是否可能塑造了一些引入种群的成功。在大尺度上，两个冰期避难所促成了丁鱥的祖先和基因组多样性。然而，与主要具有单源祖先的种群相比，混合起源的本土、引入和养殖种群表现出多达10倍的遗传多样性（即观察到的杂合度、预期杂合度和等位基因丰富度）。引入到新地点的影响也很明显，因为引入种群与本土种群相比表现出更少的特有等位基因（引入种群和本土种群中特有等位基因的平均数分别为9.9和18.9）以及更高的种群特异性，突出了它们相对于丁鱥种群中等位基因频率库的独特性。最后，具有不同遗传变异水平和相似遗传组成的引入种群在截然不同的气候和生态条件下得以建立并持续存在。我们的结果表明，对于具有已证明的扩展其本土范围能力的物种而言，缺乏先前的适应性和低遗传变异可能并不总是会阻碍引入种群的成功。
