Data from: Fine-scale local adaptation in an invasive freshwater fish has evolved in contemporary time

Adaptive evolutionary change in only a few generations can increase the ability of non-native invasive species to spread, and yet adaptive divergence is rarely assessed in recently established populations. In this paper, we experimentally test for evidence of fine-scale local adaptation in juvenile survival and growth among three populations of an invasive freshwater fish with reciprocal transplants and common-garden experiments. Despite intrinsic differences in habitat quality, in two out of three populations we detected evidence of increased survival in ‘home’ vs. ‘away’ environments with a Bayesian occupancy model fitted to mark-recapture data. We found support for the ‘local vs. foreign’ criterion of local adaptation as 14 out of 15 pairwise comparisons of performance were consistent with local adaptation (p < 0.001). Patterns in growth were less clear, though we detected evidence of location and population-level effects. Although the agents of divergent ecological selection are not known in this system, our results combine to indicate that adaptive divergence – reflected by higher relative survival of local individuals – can occur in a small number of generations and only a few kilometers apart on the landscape.

仅需数代的适应性进化改变，便可增强非本土入侵物种的扩散能力；但针对新近定殖种群的适应性分化研究却极为匮乏。本研究以一种入侵淡水鱼类的三个种群为研究对象，通过互惠移植实验（reciprocal transplants）与同质园实验（common-garden experiments），检验其幼体存活与生长的精细尺度局部适应性证据。尽管各研究种群的栖息地质量存在固有差异，但通过拟合标记-重捕数据（mark-recapture data）的贝叶斯占有模型（Bayesian occupancy model）分析，我们在三个种群中的两个种群内，检测到了个体在原生境中的存活率显著高于异地生境的适应性证据。15组性能两两对比中有14组符合局部适应性的“本地vs外来”判定标准（p < 0.001），进一步支持了局部适应性的存在。生长模式的相关结果则相对模糊，不过我们仍检测到了生境位置与种群水平效应的相关证据。尽管本研究系统中尚未明确引发分化性生态选择的作用因子，但综合所有结果来看，我们的研究表明：以本地个体相对存活率更高为表征的适应性分化，仅需数代演化、在相距仅数公里的景观尺度生境中即可形成。