Hsiung Huan-Yi, Huang Bing-Hong, Chang Jui-Tse, Huang Yao-Moan, Huang Chih-Wei, Liao Pei-Chun
Department of Life Science, National Taiwan Normal University Taipei, Taiwan.
Department of Entomology, National Taiwan University Taipei, Taiwan.
Front Plant Sci. 2017 Feb 10;8:159. doi: 10.3389/fpls.2017.00159. eCollection 2017.
Spatial climate heterogeneity may not only affect adaptive gene frequencies but could also indirectly shape the genetic structure of neutral loci by impacting demographic dynamics. In this study, the effect of local climate on population genetic variation was tested in two phylogenetically close species in Taiwan. , which was originally assumed to be an endemic species of Taiwan Island, is shown to be part of the widespread species based on the overlapping ranges of genetic variation and climatic niches as well as their morphological similarity. Rejection of the scenario of "early divergence with secondary contact" and the support for multiple origins of populations of from provide strong evolutionary evidence for a taxonomic revision of the species combination. Further tests of a climatic effect on genetic variation were conducted. Regression analyses show nonlinear correlations among any pair of geographic, climatic, and genetic distances. However, significantly, the bioclimatic variables that represent the precipitation from late summer to early autumn explain roughly 13% of the genetic variation of our sampled populations. These results indicate that spatial differences of precipitation in the typhoon season may influence the regeneration rate and colonization rate of local populations. The periodic typhoon episodes explain the significant but nonlinear influence of climatic variables on population genetic differentiation. Although, the climatic difference does not lead to species divergence, the local climate variability indeed impacts the spatial genetic distribution at the population level.
空间气候异质性不仅可能影响适应性基因频率，还可能通过影响种群动态间接塑造中性位点的遗传结构。在本研究中，我们在台湾的两个亲缘关系较近的物种中测试了当地气候对种群遗传变异的影响。基于遗传变异和气候生态位的重叠范围以及它们的形态相似性，原本被认为是台湾岛特有物种的[物种名称1]，被证明是广泛分布物种[物种名称2]的一部分。对“早期分化与二次接触”假说的否定以及对[物种名称1]种群多起源的支持，为物种组合的分类学修订提供了有力的进化证据。我们进一步测试了气候对遗传变异的影响。回归分析表明，地理、气候和遗传距离的任意两两之间均存在非线性相关性。然而，显著的是，代表夏末至秋初降水的生物气候变量解释了我们采样种群约13%的遗传变异。这些结果表明，台风季节降水的空间差异可能影响当地种群的更新率和定殖率。周期性的台风事件解释了气候变量对种群遗传分化的显著但非线性影响。虽然气候差异并未导致物种分化，但当地气候变异性确实影响了种群水平上的空间遗传分布。
