Reproductive senescence in female Soay sheep: variation across traits and contributions of individual ageing and selective disappearance

摘要: Summary Although senescence in reproductive success has been observed a number of wild animal populations, longitudinal analyses determining the actual processes responsible for population-level patterns ageing, and particular, relative contributions within-individual vs. selective mortality, are rare. Furthermore, many studies also only consider single traits isolation, despite evidence that different aspects physiology fitness may show varying senescence. We used data from an unmanaged population Soay sheep on islands St Kilda, NW Scotland to analyse age-related change four female performance: annual fecundity, twinning rate maternally influenced offspring lamb birth weight early survival. We present results three analytical techniques, which attempt disentangle mortality terminal effects age-specific change. All showed considerable change, but trajectories varied markedly across them. Population-level were underpinned by including declines performance occurring final year life. However, at level, these masked some extent disappearance (mortality) poor breeders. The individual-level ageing considerably between traits, as did nature senescence. not observe detectable significant late-life all traits: there was no rate. The indicate be ubiquitous within population.