Data from: Male mate choice via cuticular hydrocarbon pheromones drives reproductive isolation between Drosophila species

Mate discrimination is a key mechanism restricting gene flow between species. While studied extensively with respect to female mate choice, mechanisms of male mate choice between species are far less studied. Thus, we have little knowledge of the relative frequency, importance, or overall contribution of male mate discrimination to reproductive isolation. In the present study, we estimated the relative contributions of male and female choice to reproductive isolation between Drosophila simulans and D. sechellia, and show that male mate discrimination accounts for the majority of the current isolation between these species. We further demonstrate that males discriminate based on female cuticular hydrocarbon pheromones, and collect evidence supporting the hypothesis that male mate discrimination may alleviate the costs associated with heterospecific courtship and mating. Our findings highlight the potentially significant contribution of male mate choice to the formation of reproductive isolating barriers, and thus the speciation process.

配偶识别是限制物种间基因交流的关键机制。尽管雌性配偶选择已得到广泛研究，但物种间雄性配偶选择的相关机制却鲜有探讨。因此，我们对雄性配偶识别在生殖隔离中的相对发生频率、重要性及其整体贡献尚缺乏足够认知。本研究中，我们评估了雄性与雌性配偶选择对拟暗果蝇（Drosophila simulans）与塞舌尔果蝇（Drosophila sechellia）间生殖隔离的相对贡献，并证实雄性配偶识别构成了当前这两个物种间生殖隔离的主体部分。我们进一步证实，雄性会依据雌性的表皮碳氢化合物信息素进行识别，并收集证据支持如下假说：雄性配偶识别可减轻异种求偶与交配所带来的代价。本研究结果凸显了雄性配偶选择对生殖隔离屏障形成乃至物种形成过程的潜在重要贡献。