Mechanisms of Group Dynamics in Meerkats

合作繁殖在进化生物学中具有重要的意义，并且雌性之间的竞争与性选择的操作的相关性正在得到重视；然而，在合作系统中，生殖状态的决定因素（繁殖者vs.帮助者）和女性攻击的潜在机制仍然知之甚少。从生殖抑制、驱逐和杀婴的证据来看，很明显，社会支配在女性竞争中起着关键作用。然而，目前尚不清楚的是，哪些因素会影响女性成为主导。本项目研究了南非喀拉哈里沙漠合作繁殖猫鼬的近端内分泌、社会和嗅觉机制，这些机制有助于获得等级和繁殖倾斜。该项目将采用综合的方法，结合激素、形态、行为和化学分析，绘制雌性猫鼬从受孕到传播后的发育轨迹，跨越三个生命阶段（胎儿期、幼年期和成年期）。它将检查通常与女性支配地位的获得和表达有关的因素，并将测试通过产前暴露于雄激素的女性“男性化”是否会影响这些因素。整合跨措施、生命阶段、治疗组和长期生态数据获得的信息，将为了解社会和生殖不平等的发展、维持和信号传导机制提供有价值的见解，从而有可能揭示合作和女性生殖倾斜进化的新机制。该项目更广泛的影响来自(1)培养本科生、研究生和博士后，特别是来自代表性不足的群体；(2)促进部门间和国际合作；(3)提高教育和公众意识。后者将通过让所有团队成员参与科学发现的交流和传播，与地球观察合作，为面向公众、学校和研究人员的纪录片和网站（喀拉哈里猫鼬之友项目）提供新信息，以及促进和扩大实地课程的参与来实现。

Cooperative breeding is of significant interest in evolutionary biology and the relevance of female-female competition to the operation of sexual selection is gaining appreciation; yet, the determinants of reproductive status (breeder vs. helper) in cooperative systems and the mechanisms underlying female aggression remain poorly understood. From evidence of reproductive suppression, eviction, and infanticide, it is clear that social dominance plays a key role in female competition. What remains unclear, however, are the factors that influence which females become dominant. This project examines the proximal endocrine, social, and olfactory mechanisms that contribute to rank acquisition and reproductive skew in the cooperatively breeding meerkat of the South African Kalahari Desert. Using an integrated approach that combines hormonal, morphological, behavioral, and chemical analyses, this project will chart the developmental trajectory of female meerkats from conception to post dispersal, spanning three life stages (the fetal period, juvenility, and adulthood). It will examine the factors that are normally associated with acquisition and expression of female dominance and will test if female 'masculinization' through prenatal androgen exposure influences those factors. Integrating the information obtained across measures, life stages, treatment groups, and long-term ecological data will provide valuable insight into the development, maintenance, and signaling mechanisms of social and reproductive inequity to potentially reveal a novel mechanism in the evolution of cooperation and female reproductive skew. The project's broader impacts derive from (1) training undergraduates, graduates, and postdoctoral associates, especially from underrepresented groups, (2) fostering interdepartmental and international collaborations, and (3) increasing education and public awareness. The latter will be achieved by involving all team members in the communication and dissemination of scientific findings, partnering with Earthwatch, contributing new information to documentaries and websites (Friends of the Kalahari Meerkat Project) aimed for the general public, schools, and researchers, and contributing to and expanding participation in field courses.