![]() Our understanding of the evolution of ageing and how reproduction affects it has advanced greatly from research on Drosophila melanogaster. The trade-off between survival and reproduction has long been recognised as a prominent feature of life history trajectories and it is well established that reproduction reduces lifespan in many species 7. Such alleles have the potential to generate genetic trade-offs among life history traits and constrain their independent evolution 3, 6. These trade-offs are important because they enable the accumulation of alleles with deleterious effects that are only expressed late in life (mutation accumulation 2) and/or cause antagonistic pleiotropic effects on alleles, where genes that have positive effects on fitness early in life have deleterious effects on later survival (antagonistic pleiotropy 3). The Disposable Soma theory suggests that trade-offs result from the partitioning of finite resources between growth, maintenance and reproduction 5. ![]() Theory proposes that senescence evolves as a result of decreased selection on genes expressed late in life as few individuals reach old age due to extrinsic mortality factors 2, 3, 4, 5. Senescence is defined as decreasing reproductive performance and increasing probability of death with age 1. More generally, our data show that, like males, females can exhibit a live fast die young life history strategy. We discuss the potential role of sexual conflict in driving the evolutionary trade-off between reproduction and lifespan in Drosophila. ![]() Our findings indicate that, in addition to the well-known male-driven direct costs of mating on female lifespan (mediated by male harassment and harmful effects of seminal fluids), females with a genetic propensity to mate multiply live shorter lives. Thus, despite heritable variation in both traits, their independent evolution is constrained by an evolutionary trade-off. There was significant negative genetic covariance between these traits indicating that females from families characterized by high levels of multiple mating early in life die sooner than females that engage in less intense early life mating. We found significant additive genetic variance in longevity independent of lifetime mating frequency and in early life mating frequency. Sexual conflict may also drive a genetic trade-off between reproduction and lifespan in females. Sexual selection is expected to favour a ‘live fast die young’ life history pattern in males due to increased risk of extrinsic mortality associated with obtaining mates. The trade-off between survival and reproduction is fundamental to life history theory. ![]()
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