Kovach Ryan P, Gharrett Anthony J, Tallmon David A
Biology and Wildlife Department Institute of Arctic Biology University of Alaska Fairbanks Fairbanks AK USA.
School of Fisheries and Oceanic Sciences University of Alaska Fairbanks Juneau AK USA.
Evol Appl. 2013 Apr 18;6(5):795-807. doi: 10.1111/eva.12066. eCollection 2013 Jul.
Though genetic diversity is necessary for population persistence in rapidly changing environments, little is known about how climate-warming influences patterns of intra-population genetic variation. For a pink salmon population experiencing increasing temperatures, we used temporal genetic data (microsatellite = 1993, 2001, 2009; allozyme = 1979, 1981, 1983) to quantify the genetic effective population size ( ) and genetic divergence due to differences in migration timing and to estimate whether these quantities have changed over time. We predicted that temporal trends toward earlier migration timing and a corresponding loss of phenotypic variation would decrease genetic divergence based on migration timing and . We observed significant genetic divergence based on migration timing and genetic heterogeneity between early- and late-migrating fish. There was also some evidence for divergent selection between early- and late-migrating fish at circadian rhythm genes, but results varied over time. Estimates of from multiple methods were large (>1200) and / generally exceeded 0.2. Despite shifts in migration timing and loss of phenotypic variation, there was no evidence for changes in within-population genetic divergence or over the course of this study. These results suggest that in instances of population stability, genetic diversity may be resistant to climate-induced changes in migration timing.
虽然遗传多样性对于种群在快速变化的环境中持续存在是必要的，但对于气候变暖如何影响种群内遗传变异模式却知之甚少。对于一个经历温度上升的粉鲑种群，我们使用了时间遗传数据（微卫星数据 = 1993年、2001年、2009年；等位酶数据 = 1979年、1981年、1983年）来量化遗传有效种群大小（ ）以及由于迁移时间差异导致的遗传分化，并估计这些数量是否随时间发生了变化。我们预测，迁移时间提前的时间趋势以及相应的表型变异丧失将基于迁移时间和 降低遗传分化。我们观察到基于迁移时间以及早迁和晚迁鱼类之间的遗传异质性存在显著的遗传分化。也有一些证据表明，在昼夜节律基因方面，早迁和晚迁鱼类之间存在趋异选择，但结果随时间而变化。多种方法得出的 估计值很大（>1200），并且 / 通常超过0.2。尽管迁移时间发生了变化，表型变异也有所丧失，但在本研究过程中，没有证据表明种群内遗传分化或 发生了变化。这些结果表明，在种群稳定的情况下，遗传多样性可能对气候引起的迁移时间变化具有抗性。
