Data from: Sex-specific pathways of parental age effects on offspring lifetime reproductive success in a long-lived seabird

The conditions under which individuals are reared vary and sensitivity of offspring to such variation is often sex-dependent. Parental age is one important natal condition with consequences for aspects of offspring fitness, but reports are mostly limited to short-term fitness consequences and do not take into account offspring sex. Here we used individual-based data from a large colony of a long-lived seabird, the common tern Sterna hirundo, to investigate longitudinal long-term fitness consequences of parental age in relation to both offspring and parental sex. We found that recruited daughters from older mothers suffered from reduced annual reproductive success. Recruited sons from older fathers were found to suffer from reduced lifespan. Both effects translated to reductions in offspring lifetime reproductive success. Besides revealing novel sex-specific pathways of trans-generational parental age effects on offspring fitness, which inspire studies of potential underlying mechanisms, our analyses show that reproductive senescence is only observed in the common tern when including trans-generational age effects. In general, our study shows that estimates of selective pressures underlying the evolution of senescence, as well as processes such as age-dependent mate choice and sex allocation, will depend on whether causal trans-generational effects exist and are taken into account.个体发育所处的环境条件存在异质性，后代对这类环境变异的敏感性通常呈现性别依赖性。亲本年龄是影响子代适合度的重要发育早期环境因素之一，但现有研究大多仅关注短期的子代适合度效应，且未考虑子代性别这一变量。本研究以长寿海鸟普通燕鸥（Sterna hirundo）的大型繁殖种群为研究对象，基于个体水平的观测数据，探究亲本年龄与子代、亲本自身性别相关联的子代适合度长期纵向效应。我们发现，由高龄母亲所产且成功招募入种群的雌性子代，其年度繁殖成功率显著降低；由高龄父亲所产且成功招募入种群的雄性子代，其寿命显著缩短。这两种效应均会导致子代的终生繁殖适合度下降。本研究不仅揭示了亲本年龄通过性别特异性通路对子代适合度产生跨代影响的全新路径，为潜在内在作用机制的相关研究提供了方向，同时分析结果表明：仅当纳入跨代年龄效应时，普通燕鸥种群中才会观测到繁殖衰老现象。总体而言，本研究表明，针对衰老演化背后的选择压力，以及年龄依赖的配偶选择、性分配等相关过程的评估，将取决于是否存在因果性跨代效应，以及是否将这类效应纳入研究考量范畴。