Intralocus sexual conflict can resolve the male-female health-survival paradox

At any given age, men are more likely to die than women, but women have poorer health at older ages. This is referred to as the “male-female, health-survival paradox”, which is not fully understood. Here, we provide a general solution to the paradox that relies on intralocus sexual conflict, where alleles segregating in the population have late-acting positive effects on male fitness, but negative effects on female health. Using an evolutionary modelling framework we show that male-benefit, female-detriment alleles can spread if they are expressed after female reproduction stops. We provide support for our conflict based solution using experimental Drosophila data. Our results show that selecting for increased late-life male reproductive effort can increase male fitness but have a detrimental effect on female fitness. Furthermore, we show that late-life male fertility is negatively genetically correlated with female health. Our study suggests that intralocus sexual conflict could resolv...在任意给定年龄，男性的死亡风险均高于女性，但老年女性的健康状况却更差。这一现象被称为「性别健康-生存悖论（male-female, health-survival paradox）」，目前尚未得到完全阐释。本研究针对该悖论提出了一种基于基因座内性冲突（intralocus sexual conflict）的普适性解决方案：种群中分离的等位基因（alleles）会对男性适合度产生迟发性正向效应，却对女性健康产生负向影响。借助进化建模框架，我们证实：若雄性获益、雌性受损的等位基因在雌性生育期结束后才得以表达，便可在种群中扩散。我们通过实验果蝇（Drosophila）数据为该基于性冲突的解决方案提供了实证支撑。研究结果显示，针对雄性晚年生殖投入进行定向选育，可提升雄性适合度，却会对雌性适合度产生损害。此外，我们还发现雄性晚年生育力与雌性健康之间存在负向遗传相关性。本研究表明，基因座内性冲突或可解决……