Data from: The influence of weather conditions during gestation on life histories in a wild Arctic ungulate

The internal predictive adaptive response (internal PAR) hypothesis predicts that individuals born in poor conditions should start to reproduce earlier if they are likely to have reduced performance in later life. However, whether this is the case remains unexplored in wild populations. Here, we use longitudinal data from a long-term study of Svalbard reindeer to examine age-related changes in adult female life-history responses to environmental conditions experienced in utero as indexed by rain-on-snow (ROSutero). We show that females experiencing high ROSutero had reduced reproductive success only from 7 years of age, independent of early reproduction. These individuals were able to maintain the same annual reproductive success between 2 and 6 years as phenotypically superior conspecifics that experienced low ROSutero. Young females born after high ROSutero engage in reproductive events at lower body mass (about 2.5 kg less) than those born after low ROSutero. The mean fitness of females that experienced poor environmental conditions in early life was comparable with that of females exposed to good environmental conditions in early life. These results are consistent with the idea of internal PAR and suggest that the life-history responses to early-life conditions can buffer the delayed effects of weather on population dynamics.内部预测性适应性反应（internal predictive adaptive response）假说提出，若个体在晚年的适合度表现可能下降，则出生于恶劣环境中的个体应更早启动繁殖。然而，这一假说在野生种群中仍未得到验证。本研究依托斯瓦尔巴群岛驯鹿（Svalbard reindeer）的长期纵向监测数据，以子宫内雪面降雨暴露（rain-on-snow, ROSutero）为指标，探究成年雌性个体的生活史响应随年龄的变化规律，及其与子宫内环境条件的关联。研究结果显示，子宫内高ROSutero暴露的雌性个体，仅在7龄及之后才出现繁殖成功率下降的情况，且该效应不受早期繁殖行为的影响。此类个体在2至6龄期间的年繁殖成功率，与子宫内低ROSutero暴露的表型更优的同种个体相当。子宫内高ROSutero暴露的年轻雌性，参与繁殖活动时的体质量较低暴露组个体低约2.5千克。早年暴露于恶劣环境的雌性个体的平均适合度，与早年环境良好的雌性个体相当。上述研究结果与内部预测性适应性反应假说一致，表明针对早期生活环境的生活史响应，能够缓冲天气变化对种群动态的滞后效应。