Mechanisms of age-related change in performance in a wild social bird: parental age effects, cellular senescence, and dominance acquisition

人类和野生动物通常在晚年表现出健康和健康水平的下降，这一现象被称为衰老。这些与年龄相关的下降的原因现在是进化生物学和生物医学研究的一个关键焦点。虽然到目前为止，大多数研究都集中在个体随着年龄的增长所面临的困境，但人们很快发现，衰老的一个主要组成部分是父母年龄对后代健康状况的跨代影响。然而，母亲和父亲年龄效应的相对重要性以及产生它们的机制仍然知之甚少。鉴于亲代年龄效应在人类和野生动物种群的健康和衰老轨迹中可能起到的关键作用，这一点意义重大。这个项目将首次测试端粒(保持染色体完整性的核蛋白复合体)在野生脊椎动物中产生亲代年龄效应中所起的作用。虽然对人类和野生脊椎动物的研究已经强调了亲代年龄对后代端粒长度的潜在影响，但对这些影响的全面实地研究尚未进行。该项目将结合对卡拉哈里沙漠野生鸟类研究种群的纵向实地研究(白眉麻雀编织者；PLocepasser Mahali)对端粒长度进行了细致的分析，并对现有的生活史、行为和遗传数据集进行了统计建模，以调查：(I)母系和父系年龄对后代端粒的影响，(Ii)这些效应在多大程度上可归因于年龄对父母投资或配子端粒长度的影响，以及(Iii)父母年龄对后代端粒的影响在多大程度上可以解释父母年龄对后代健康的影响。

Humans and wild animals typically show late-life declines in fitness and health, a phenomenon knownas senescence. The causes of these age-related declines are now a key focus of research inevolutionary biology and biomedicine. While most work to date has focussed on the plight ofindividuals as they age, it is fast becoming clear that a major component of senescence arises fromtrans-generational effects of the age of parents on the fitness of their offspring. However, the relativeimportance of maternal and paternal age effects and the mechanisms that generate them remainpoorly understood. This is significant, given the key role that parental age effects may play ingenerating individual variation in health and ageing trajectories in both human and wild animalpopulations.This project will provide the first test of the role that telomeres (nucleoprotein complexes thatpreserve chromosomal integrity) play in generating parental age effects in a wild vertebrate. Whileresearch on humans and wild vertebrates has highlighted the potential for parental age effects onoffspring telomere lengths, comprehensive field studies of these effects have yet to be conducted.This project will combine longitudinal field research on an established study population of wild birdsin the Kalahari desert (the white-browed sparrow weaver; Plocepasser mahali) with cutting edgelaboratory analyses of telomere length and statistical modelling of existing life-history, behaviouraland genetic data sets to investigate: (i) maternal and paternal age effects on offspring telomeres, (ii)the extent to which these can be attributed to age effects on parental investment or gamete telomerelengths, and (iii) the extent to which parental age effects on offspring telomeres can account forparental age effects on offspring fitness.