Data from: Cross–generational effects of sexual harassment on female fitness in the guppy

A large number of studies have identified several direct costs of sexual harassment, including energy expenditure and reduced foraging ability. However, the fitness consequences of sexual harassment over a longer time-scale have never been investigated. Here, we estimated the effects of male sexual harassment on female fitness in the guppy, Poecilia reticulata, a small tropical fish in which sexual conflict over mating rates is particularly pronounced. We compared the lifetime fecundity and survival of two groups of females exposed to different levels of sexual harassment. We further estimated the effect of sexual harassment on the fitness of the second generation by raising the offspring to maturity and measuring traits associated with fecundity in daughters and with pre- and post-copulatory competitiveness in sons. Although sexual harassment did not reduce mothers’ lifetime fecundity, it affected their timing of reproductive allocation. Interestingly, sexually harassed females produced daughters with smaller body size and sons that were less attractive to females and less successful in achieving coercive copulations than the sons of control females. This study provides compelling evidence that sexual harassment can have negative cross-generational fitness effects, suggesting that its consequences on female fitness may be more profound than currently thought.既往大量研究已明确性骚扰存在多项直接成本，涵盖能量消耗与觅食能力衰退。然而，长时程尺度下性骚扰所带来的适合度（fitness）后果，此前从未得到系统研究。本研究以孔雀鱼（Poecilia reticulata）——一种在交配率相关性冲突上表现尤为显著的小型热带鱼类——为实验对象，评估了雄性性骚扰对雌性适合度的影响。我们设置了两组暴露于不同性骚扰强度环境下的雌性个体，对比了二者的终身繁殖力与存活状况。此外，我们通过将子代饲养至性成熟，测量雌性后代与繁殖力相关的性状、雄性后代交配前与交配后的竞争力，进一步探究了性骚扰对第二代适合度的影响。尽管性骚扰并未降低母代个体的终身繁殖力，但却改变了其生殖分配的时间模式。值得注意的是，遭受性骚扰的雌性所产下的雌性后代体型更小；而雄性后代相较于对照组雌性的子代，对雌性的吸引力更弱，且成功完成强制交配的概率更低。本研究提供了确凿证据，表明性骚扰可产生负面的跨代适合度效应，这意味着性骚扰对雌性适合度的影响或远超当前学界的认知。