Breaking the parthenogenesis fertilization barrier: direct and indirect selection pressures promote male fertilization of parthenogenetic females
Breaking the parthenogenesis fertilization barrier: direct and indirect selection pressures promote male fertilization of parthenogenetic females
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DOI：
10.1007/s10682-014-9749-0
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发表时间：
2015-01-01
影响因子：
1.9
通讯作者：
Kawatsu, Kazutaka
中科院分区：
文献类型：
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作者：
Kawatsu, Kazutaka
在其他条件相同的情况下，雌性通过孤雌生殖，其生育力会加倍。另一方面，雄性应该受到积极的选择压力，以迫使孤雌生殖的雌性进行有性受精，因为孤雌生殖的双重优势是通过牺牲雄性遗传贡献来实现的。有趣的是，尽管雄性强制表面上给孤雌生殖雌性强加了性成本，但它甚至会给孤雌生殖带来生殖益处。这是因为，被强制雄性受精的雌性通过继承强制的儿子获得了间接的繁殖成功，而儿子将在下一代成功地与其他孤雌生殖交配（儿子效应）。在这项研究中，我使用两个数学模型，首次表明，雄性强制的间接儿子效应在潜在孤雌生殖物种的性维持中发挥着重要作用。第一个模型将雌性孤雌生殖的适应性与雌性与强制雄性交配的适应性进行了比较，表明儿子的影响可以超过性的成本并解决生殖模式上的性冲突。我的第二个群体遗传学模型分析了强迫和孤雌生殖的动态，表明孤雌生殖的发生在男性强迫的儿子效应的存在下受到抑制。这些结果表明，雄性胁迫的儿子效应有助于在进化时间尺度上维持有性生殖，并抵消雄性在胁迫入侵阶段的双重成本。
All else being equal, females would double their fecundity through parthenogenetic reproduction. On the other hand, males should be subject to positive selection pressures to coerce parthenogenetic females into sexual fertilization, because the twofold advantage of parthenogenesis is achieved at the expense of the male genetic contribution. Interestingly, although male coercion superficially imposes the cost of sex on parthenogenetic females, it would confer a reproductive benefit even on the parthenogens. This is because females fertilized by coercive males gain indirect reproductive success via sons inheriting coercion, who would succeed in mating with other parthenogens in the next generation (sons' effect). In this study, using two mathematical models, I show for the first time that the indirect sons' effect of male coercion plays an important role in the maintenance of sex in potentially parthenogenetic species. The first model, which compares the fitness of a female reproducing parthenogenetically with that of a female mating with a coercive male, demonstrates that the sons' effect can outweigh the cost of sex and resolve sexual conflict over reproductive modes. My second model of population genetics, which analyses the dynamics of coercion and parthenogenesis, shows that the occurrence of parthenogenetic reproduction is suppressed in the presence of the sons' effect of male coercion. These results indicate that the sons' effect of male coercion helps to maintain sexual reproduction at an evolutionary time scale, as well as offset the twofold cost of males in the invasion phase of the coercion.