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Yosemite National Park, PO Box 700, El Portal, CA 95318, USA.
Trends Ecol Evol. 2021 Jun;36(6):533-544. doi: 10.1016/j.tree.2021.02.004. Epub 2021 Mar 18.
The genetic swamping hypothesis proposes that gene flow from central to peripheral populations inhibits local adaptation and is one of the most widely recognized explanations for range limitation. We evaluated empirical support for this hypothesis in studies quantifying patterns of gene flow to peripheral populations and their resulting fitness outcomes. We found little evidence that gene flow is generally asymmetric from central to peripheral populations and also that gene flow tends to have positive effects on edge population fitness. These findings contravene the long-held assumption that genetic swamping is a common driver of species range limits, and bear important implications for understanding the role of gene flow in range evolution and for predicting and managing eco-evolutionary responses to climate change.
遗传淹没假说提出，来自中心种群向边缘种群的基因流会抑制局部适应，这是对分布范围限制最广泛的解释之一。我们通过量化基因流向边缘种群的模式及其对适应度的影响的研究，评估了该假说的经验证据。我们发现，来自中心种群向边缘种群的基因流通常是不对称的，并且基因流往往对边缘种群的适应度有积极影响，这方面的证据很少。这些发现与遗传淹没是物种分布范围限制的常见驱动因素这一长期假设相矛盾，并对理解基因流在分布范围进化中的作用以及预测和管理对气候变化的生态进化响应具有重要意义。
