Data from: Multiple mating but not recombination causes quantitative increase in offspring genetic diversity for varying genetic architectures

Explaining the evolution of sex and recombination is particularly intriguing for some species of eusocial insects because they display exceptionally high mating frequencies and genomic recombination rates. Explanations for both phenomena are based on the notion that both increase colony genetic diversity, with demonstrated benefits for colony disease resistance and division of labor. However, the relative contributions of mating number and recombination rate to colony genetic diversity have never been simultaneously assessed. Our study simulates colonies, assuming different mating numbers, recombination rates, and genetic architectures, to assess their worker genotypic diversity. The number of loci has a strong negative effect on genotypic diversity when the allelic effects are inversely scaled to locus number. In contrast, dominance, epistasis, lethal effects, or limiting the allelic diversity at each locus does not significantly affect the model outcomes. Mating number increases colony genotypic variance and lowers variation among colonies with quickly diminishing returns. Genomic recombination rate does not affect intra- and inter-colonial genotypic variance, regardless of mating frequency and genetic architecture. Recombination slightly increases the genotypic range of colonies and more strongly the number of workers with unique allele combinations across all loci. Overall, our study contradicts the argument that the exceptionally high recombination rates cause a quantitative increase in offspring genotypic diversity across one generation. Alternative explanations for the evolution of high recombination rates in social insects are therefore needed. Short-term benefits are central to most explanations of the evolution of multiple mating and high recombination rates in social insects but our results also apply to other species.

阐释有性生殖与重组的演化机制，对于部分真社会性昆虫（eusocial insects）而言尤为引人关注，因为这类昆虫展现出极高的交配频率与基因组重组率。针对这两种现象的现有解释均基于同一核心论点：二者均可提升社群遗传多样性，且已有研究证实其对社群抗病性与劳动分工具有积极作用。然而，此前从未有研究同时评估交配次数与重组率对社群遗传多样性的相对贡献。本研究通过设定不同的交配次数、重组率与遗传架构，对昆虫巢群进行模拟，以此评估其职虫的基因型多样性。当等位基因效应与基因座数量呈反比缩放时，基因座数量对基因型多样性具有显著的负向影响。与之相反，显性效应、上位性、致死效应，或是限制单个基因座的等位基因多样性，均不会对模型结果产生显著影响。交配次数可提升社群遗传方差，但会降低社群间的遗传变异，且其增益效果会快速呈现边际递减。无论交配频率与遗传架构如何，基因组重组率均不会影响社群内与社群间的遗传方差。重组会小幅提升社群的基因型范围，且更显著地增加了在所有基因座上均拥有独特等位基因组合的职虫数量。总体而言，本研究驳斥了"极高的重组率可在单代繁殖中使子代基因型多样性出现定量提升"这一论点。因此，学界需要提出新的解释，以阐明社会性昆虫高重组率的演化机制。尽管现有多数关于社会性昆虫多次交配与高重组率演化的解释均以短期收益为核心，但本研究的结论同样适用于其他物种。