Sexual selection depletes genetic variation but depleted genetic variation limits the efficacy of sexual selection-a long-standing enigma known as the lek paradox. Here we offer a twist to this paradox by showing that sexual selection and the generation of new genetic variation via mutation may be entangled in an evolutionary feedback loop. We induced DNA damage in the germline of male seed beetles evolved under regimes manipulating the opportunity for natural and sexual selection, and quantified de novo mutations in F2-F7 generations by measuring mutation load. Sexually selected males passed on smaller loads, suggesting that selection for male quality not only purges segregating deleterious alleles, but can also reduce the rate at which such alleles originate de novo. However, when engaging in socio-sexual interactions, males evolved exclusively under sexual selection transferred greater loads, suggesting that trade-offs between naturally and sexually selected fitness components can increase mutation rate. These results offer causality to the widely observed male mutation bias and have implications for the maintenance of genetic variation in fitness.

中文翻译：

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性选择对条件依赖性突变率影响的实验证据。

性选择耗尽了遗传变异，但耗尽的遗传变异限制了性选择的效力-一个长期存在的谜，称为韭菜悖论。在这里，我们通过证明性选择和通过突变产生新的遗传变异可能会纠缠在进化反馈回路中来扭转这一悖论。我们在操纵自然和有性选择机会的制度下，在雄性甲虫的种系中诱导了DNA损伤，并通过测量突变量定量了F2-F7代的从头突变。性选择的雄性通过的负荷较小，这表明选择雄性不仅清除了有害的等位基因，而且还降低了这些等位基因从头产生的速度。但是，在进行社会性别互动时，仅在性选择下进化的雄性转移了更大的负荷，这表明在自然选择的和性选择的健身成分之间进行权衡可以增加突变率。这些结果为广泛观察到的男性突变偏倚提供了因果关系，并且对保持适应性遗传变异具有影响。