Data from: Antagonistic responses to natural and sexual selection and the sex-specific evolution of cuticular hydrocarbons in Drosophila simulans

Natural and sexual selection are classically thought to oppose one another, and while there is evidence for this, direct experimental demonstrations of this antagonism are largely lacking. Here we assessed the effects of sexual and natural selection on the evolution of cuticular hydrocarbons (CHCs), a character subject to both modes of selection, in Drosophila simulans. Natural selection and sexual selection were manipulated in a fully factorial design, and after 27 generations of experimental evolution the responses of male and female CHCs were assessed. The effects of natural and sexual selection differed greatly across the sexes. The responses of female CHCs were generally small, but CHCs evolved predominantly in the direction of natural selection. For males, profiles evolved via sexual and natural selection, as well as through the interaction between the two, with some male CHC components only evolving in the direction of natural selection when sexual selection was relaxed. These results indicate sex-specific responses to selection, and that sexual and natural selection act antagonistically for at least some combinations of CHCs.

传统演化生物学观点认为，自然选择与性选择彼此拮抗，尽管已有部分证据支持这一论断，但直接验证该拮抗关系的实验研究仍较为匮乏。本研究以拟果蝇（Drosophila simulans）为研究对象，针对同时受两种选择模式作用的表皮碳氢化合物（cuticular hydrocarbons, CHCs）性状，评估了自然选择与性选择对其演化的影响。研究采用全因子实验设计操控自然选择与性选择的强度，经过27代实验演化后，对雌雄个体的表皮碳氢化合物响应特征进行了检测。结果显示，自然选择与性选择的作用效果存在显著的性别特异性：雌性表皮碳氢化合物的演化响应整体较为微弱，且其演化方向主要与自然选择一致；雄性的表皮碳氢化合物谱则同时受到性选择、自然选择以及二者交互作用的调控，部分雄性表皮碳氢化合物组分仅在性选择被解除时，才会朝着自然选择的方向发生演化。上述结果表明，不同性别对选择压力的演化响应存在特异性，且至少针对部分表皮碳氢化合物组合而言，性选择与自然选择确实存在拮抗作用。