Mechanisms and Evolution of Post-Reproductive Lifespan

生殖后寿命（PRL）是在脊椎动物和无脊椎动物的远亲类群中都存在的一个生活史阶段。对于PRL进化的最终解释仍然存在争议，促进和调节PRL的近似机制也知之甚少。生活史性状、生理条件和生态制约因素对PRL发生的潜在影响尚不清楚。在群居昆虫中，PRL可能代表了从简单的合作性社会（工蜂保留生殖潜力）向预先想象的种姓决定过渡的一个阶段，这是复杂社会的一个决定性特征。本项目将研究两种简单的热带社会纸黄蜂姐妹种Polistes lanio和Polistes canadensis的生殖潜能和PRL。热带波氏蜂的工蜂随着年龄的增长表现出生殖能力的丧失。我将通过实地实验、行为分析和实验室检查来确定PRL对“危险的”利他行为、生殖冲突和生殖生理学的功能后果。利用转录组学和基因本体，我将在这个无脊椎动物系统中确定与PRL相关的潜在分子机制。了解PRL的分子和生理机制以及表型后果将有助于深入了解复杂社会中生殖可塑性的进化和种姓身份的预先决定。

Post-reproductive lifespan (PRL) is a life history stage found in distantly related taxa in both vertebrates and invertebrates. Ultimate explanations for the evolution of PRL remain contentious, and the proximate mechanisms which facilitate and regulate PRL are poorly understood. The potential influences of life history traits, physiological condition and ecological constraints on the occurrence of PRL are not known. In social insects, PRL may represent a stage in the transition from simple cooperative sociality (where workers retain reproductive potential) to pre-imaginal caste determination, a defining feature of complex eusociality. This project will investigate reproductive potential and PRL in the sister species Polistes lanio and Polistes canadensis, two simply eusocial tropical paper wasp. The workers of tropical Polistes species display loss of reproductive potential with age. I will determine the functional consequences of PRL on 'risky' altruistic behaviour, reproductive conflict and reproductive physiology through field experiments, behavioural analyses and examination in the lab. Using transcriptomics and gene ontology, I will identify potential molecular mechanisms associated with PRL in this invertebrate system. Understanding the molecular and physiological mechanisms and the phenotypic consequences of PRL will provide insights into the evolution of reproductive plasticity and the predetermination of caste identity in complex eusociality.