Ecological Determinants of Mutation Load and Inbreeding Depression in Subdivided Populations
Ecological Determinants of Mutation Load and Inbreeding Depression in Subdivided Populations
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DOI：
10.1086/653672
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发表时间：
2010-08-01
影响因子：
2.9
通讯作者：
Agrawal, Aneil F.
中科院分区：
文献类型：
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作者：
Agrawal, Aneil F.
种群结构可以极大地改变突变负荷，但这种效应的大小和方向取决于软选择还是硬选择。先前负荷模型的抽象性质掩盖了生态细节在确定选择软度方面的重要性。在此处使用的更生态明确的模型下，我表明与内在增长率相关的基因往往会经历硬选择，而那些影响竞争能力的基因则经历较软的选择。尽管资源限制决定了竞争能力选择的强度，但它只影响选择的软度，从而影响对内在增长率具有多效性影响的突变的负载。虽然竞争通常被认为是软选择所必需的，但该模型表明，种间竞争会强化选择，从而导致负载减少。最后，在繁殖前死亡的个体的消耗率的遗传变异可能导致超软选择，导致负荷大幅增加。增加突变负荷的相同条件也会增加近交衰退。
Population structure can dramatically alter mutation load, but the magnitude and direction of this effect depend on whether selection is soft or hard. The abstract nature of previous load models obscured the importance of ecological details in determining the softness of selection. Under the more ecologically explicit model used here, I show that genes related to intrinsic growth rate tend to experience hard selection whereas those genes affecting competitive ability experience softer selection. Although resource limitation determines the strength of selection on competitive ability, it only affects the softness of selection, and thus the load, of mutations with pleiotropic effects on intrinsic growth rate. While competition is typically considered necessary for soft selection, the model shows that interspecific competition hardens selection and can thereby lead to reduced load. Finally, genetic variation in the consumption rates of individuals who die before reproduction can cause supersoft selection, resulting in large increases in load. The same conditions that increase mutation load also increase inbreeding depression.