Data from: Contrasting drivers of reproductive ageing in albatrosses

1.Age-related variation in reproductive performance is ubiquitous in wild vertebrate populations and has important consequences for population and evolutionary dynamics.

2.The ageing trajectory is shaped by both within-individual processes, such as improvement and senescence, and by the among-individual effects of selective appearance and disappearance. To date, few studies have compared the role of these different drivers among species or populations.

3.In this study, we use nearly 40 years of longitudinal monitoring data to contrast the within- and among-individual processes contributing to the reproductive ageing patterns in three albatross species (two biennial and one annual breeder), and test whether these can be explained by differences in life-histories.

4.Early life performance in all species increased with age, and was predominantly influenced by within-individual improvements. However, reproductive senescence was detected in only two of the species. In the species exhibiting senescent declines, we also detected a terminal improvement in breeding success. This is suggestive of a trade-off between reproduction and survival, which was supported by evidence of selective disappearance of good breeders.

5.We demonstrate that comparisons of closely-related species which differ in specific aspects of their life-history can shed light on the ecological and evolutionary forces shaping variation in ageing patterns.

1. 繁殖表现的年龄相关变异在野生脊椎动物种群中普遍存在，并对种群动态与演化动态产生重要影响。
2. 衰老轨迹既受个体内部过程（如性能提升与衰老）的塑造，也受个体间选择性出现与消失的效应影响。迄今为止，鲜有研究在不同物种或种群间比较这些不同驱动因素的作用。
3. 本研究依托近40年的纵向监测数据，对比了三种信天翁（Albatross）的繁殖衰老模式背后的个体内部与个体间过程，其中两种为两年繁殖型、一种为每年繁殖型，并检验这些模式是否可通过生活史差异加以解释。
4. 所有物种的早期生命繁殖性能均随年龄增长而提升，且主要受个体内部性能提升的影响。然而，仅在其中两个物种中检测到繁殖衰老现象。在出现繁殖衰老衰退的物种中，我们还观测到繁殖成功率的终末提升现象，这提示繁殖与存活之间存在权衡，而优质繁殖个体的选择性消失相关证据也支持了这一权衡假说。
5. 本研究表明，对生活史特定维度存在差异的近缘物种进行比较，可揭示塑造衰老模式变异的生态与演化力量。