Migration and recovery of the genetic diversity during the increasing density phase in cyclic vole populations
Migration and recovery of the genetic diversity during the increasing density phase in cyclic vole populations
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DOI：
10.1111/j.1365-294x.2006.02959.x
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发表时间：
2006-08-01
影响因子：
4.9
通讯作者：
Cosson, J. -F.
中科院分区：
文献类型：
--
作者：
Berthier, K.;Charbonnel, N.;Cosson, J. -F.
在周期性种群中，尽管种群在低阶段经历了周期性的低数量，但目前报道了高遗传多样性。在这里，我们报告的时空监测在一个非常精细的尺度循环种群的fossorial水田鼠（Arvicola terrestris）在密度增加阶段。这一阶段标志着从低密度时的斑块结构（demes）到高密度时的连续种群的过渡。我们发现，遗传多样性是有效的高，但它也显示出一个本地的增加，在不断增长的阶段。遗传多样性保持相对恒定，当考虑所有的部落在一起。田鼠丰度的增加也与种群间遗传分化的减少有关。这些结果表明，在低阶段结束时，由于规模小和地理隔离，种群受到遗传漂变的影响。这导致当地遗传多样性的丧失和部落之间的空间分化。在增长阶段，这种情况被demes的空间扩张和分化demes之间有效移徙的增加所抵消。我们提供的证据表明，在循环种群的fossorial水田鼠，漂移的相对影响，在低密度的人口和迁移主要发生在人口规模的增加相互作用密切，以保持高的遗传多样性。
In cyclic populations, high genetic diversity is currently reported despite the periodic low numbers experienced by the populations during the low phases. Here, we report spatio-temporal monitoring at a very fine scale of cyclic populations of the fossorial water vole (Arvicola terrestris) during the increasing density phase. This phase marks the transition from a patchy structure (demes) during low density to a continuous population in high density. We found that the genetic diversity was effectively high but also that it displayed a local increase within demes over the increasing phase. The genetic diversity remained relatively constant when considering all demes together. The increase in vole abundance was also correlated with a decrease of genetic differentiation among demes. Such results suggest that at the end of the low phase, demes are affected by genetic drift as the result of being small and geographically isolated. This leads to a loss of local genetic diversity and a spatial differentiation among demes. This situation is counterbalanced during the increasing phase by the spatial expansion of demes and the increase of the effective migration among differentiated demes. We provide evidences that in cyclic populations of the fossorial water voles, the relative influence of drift operating during low density populations and migration occurring principally while population size increases interacts closely to maintain high genetic diversity.