Divergent selection on behavioural and chemical traits between reproductively isolated populations of Drosophila melanogaster

Speciation is driven by traits that can act to prevent mating between nascent lineages, including male courtship and female preference for male traits. Mating barriers involving these traits evolve quickly because there is strong selection on males and females to maximize reproductive success, and the tight co-evolution of mating interactions can lead to rapid diversification of sexual behavior. Populations of D. melanogaster show strong asymmetrical reproductive isolation that is correlated with geographic origin. Using strains that capture natural variation in mating traits, we ask two key questions: which specific male traits are females selecting, and are these traits under divergent sexual selection? These questions have proven extremely challenging to answer, because even in closely related lineages males often differ in multiple traits related to mating behavior. We address these questions by estimating selection gradients for male courtship and cuticular hydrocarbons for two dif..., ,

物种形成由可阻断新生谱系间交配的性状驱动，此类性状涵盖雄性求偶行为与雌性对雄性性状的偏好。涉及此类性状的交配障碍演化速率极快，原因在于雌雄个体均面临以最大化繁殖成功率为目标的强烈选择压力，而交配互动的紧密共进化可推动性行为快速多样化。黑腹果蝇（D. melanogaster）种群呈现出强烈的不对称生殖隔离，且该隔离特征与其地理起源存在相关性。本研究借助携带交配性状自然变异的实验品系，提出两项核心研究问题：雌性所选择的雄性具体性状为何？此类性状是否经受歧化性选择？此类问题历来极难解答，因为即便在亲缘关系极近的谱系中，雄性往往也存在多项与交配行为相关的性状差异。本研究通过估算雄性求偶行为与表皮碳氢化合物（cuticular hydrocarbons）的选择梯度，对上述问题展开探究，共涉及两组……