Data from: Intralocus sexual conflict and the tragedy of the commons in seed beetles

The evolution of male traits that inflict direct harm on females during mating interactions can result in a "tragedy of the commons", where selfish male strategies depress population viability. Tragedy of the commons can be magnified by intralocus sexual conflict (IaSC), whenever alleles that reduce fecundity when expressed in females spread in the population because of their benefits in males. We evaluated this prediction by detailed phenotyping of 73 isofemale lines of the seed beetle Callosobruchus maculatus. We quantified genetic variation in life history and morphology, as well as associated covariance in male and female adult reproductive success. In parallel, we created replicated artificial populations of each line and measured their productivity. Genetic constraints limited independent trait expression in the sexes and we identified several instances of sexually antagonistic covariance between traits and fitness, signifying IaSC. Population productivity was strongly positively correlated to female adult reproductive success, but uncorrelated with male reproductive success. Moreover, male (female) phenotypic optima for several traits under sexually antagonistic selection were exhibited by the genotypes with lowest (highest) population productivity. Our study forms a direct link between individual-level sex-specific selection and population demography, and places life history traits in the epicenter of these dynamics.在交配互动过程中对雌性造成直接伤害的雄性性状的演化，可能引发“公地悲剧”：即自私的雄性策略会降低种群存续能力。当因在雄性中具有适应性优势而在种群中扩散的等位基因，在雌性中表达时会降低其繁殖力时，基因座内性冲突（intralocus sexual conflict, IaSC）会加剧公地悲剧效应。我们以四纹豆象（Callosobruchus maculatus）的73个单雌系为研究对象，通过精细的表型鉴定验证了这一理论预测。我们量化了其生活史与形态学的遗传变异，以及雌雄成虫繁殖成功率间的相关协方差。同时，我们为每个单雌系构建了重复人工种群，并测定了其种群生产力。遗传约束限制了两性性状的独立表达，我们还鉴定出多个性状与适合度间存在性拮抗协方差的实例，这表明存在IaSC。种群生产力与雌性成虫繁殖成功率呈显著正相关，但与雄性繁殖成功率无关联。此外，针对经历性拮抗选择的多个性状，其雄性（雌性）表型最优值对应的基因型，恰好对应最低（最高）的种群生产力。本研究建立了个体水平的性别特异性选择与种群动态之间的直接联系，并将生活史性状置于这些动态过程的核心位置。