Collective action, reciprocity and kinship in blue monkey society

因为人类本质上是合作的生物，所以了解合作系统的演化对于理解人类的社会行为是至关重要的。特别令人感兴趣的是公共物品场景，比如清理社区公园，甚至发动战争。这种集体行动的坚持令人费解，因为个人最好的策略是搭便车：搭便车的人从他人的行动中获益，但自己并不为公共利益做出贡献。尽管搭便车有明显的好处，但集体行动确实在人类社会中持续存在，在人类社会中，集体行动往往无法用帮助亲属的好处来解释。它在非人类灵长类动物社会中的类似坚持表明，理解这种形式的合作行为的进化基础需要我们超越我们自己的物种，看看它的近亲。然而，在非人类灵长类动物中，参与集体行动的个体的策略很少被研究。这个项目聚焦于野生猴子的集体行动，并测试了关于这种令人费解但持久的社会合作形式演变的不同假设。PiMarina Cords将领导一个国际野战小组检查非洲蓝猴的共同领土防御。群体之间的攻击性几乎完全由雌性实施，在这个物种中很重要，因此这是一个很好的模型系统。野外研究小组将收集四个野生猴群中雌性猴子行为的观测数据，这四个野生猴群是肯尼亚卡卡梅加森林长期研究种群的一部分。观察将包括参与群体间的攻击、群体内的梳理和喂养容忍。研究小组将使用这些数据来评估女性是否会回报不同行为类型的合作。例如，经常参加领土防御的雌性是否比不经常参与的雌性更容易从队友那里得到梳理，或在觅食地点获得宽容？通过更频繁地参加领土防御或美容而获得良好声誉的女性，是否会在请求合作时更容易得到合作？行为的进化论研究关注不同行为程序的成本和收益。虽然获得互惠合作是合作的一个好处，但理论表明，还有其他潜在的重要因素。这项研究还将调查合作与个人风险、身体和生殖条件的关系，以及伴侣是亲属的程度。亲属选择理论预测，合作将是裙带关系的。谱系记录和遗传分析将允许对母系和父系亲属关系进行评估，亲属选择理论的预测将通过行为数据进行检验。因此，现场工作将包括收集粪便样本，从中提取DNA用于亲子关系分析。DNA分析，包括开发几个新的标记，将在联席Pi Todd Disotell，的监督下进行。研究父系亲属关系的影响是社会合作研究中的一个新焦点，该项目将提供关于父系亲属关系在多大程度上驱动社会行为的有价值的比较数据。这项研究的更广泛影响包括培养美国和外国学生，包括研究生和本科生，以及博士后研究员。还将促进与一所肯尼亚大学的国际合作。PI在现场的长期存在将通过当地社区保护教育计划继续为雨林保护战略做出贡献。

Because humans are fundamentally cooperative creatures, understanding the evolution of cooperative systems is essential to understanding human social behavior. Of particular interest are public goods scenarios, like neighborhood clean-ups of public parks or even waging war. The persistence of this collective action is enigmatic since an individual's best strategy is "free riding": free-riders reap the benefit of others' actions, but do not contribute to the public good themselves. Despite apparent advantages of free-riding, collective action does persist in human societies, where it often cannot be explained in terms of the benefits of helping relatives. Its similar persistence in the societies of non-human primates suggests that understanding the evolutionary basis of this form of cooperative behavior requires us to look beyond our own species at its close relatives. In non-human primates, however, strategies of individuals that engage in collective action have been very little examined. This project focuses on collective action in wild monkeys and tests different hypotheses about the evolution of this puzzling but persistent form of social cooperation. PI Marina Cords will lead an international field team in examining communal territorial defense by African blue monkeys. Aggression between groups, carried out almost exclusively by females, is important in this species, which therefore makes a good model system. The field team will collect observational data on the behavior of females in four wild monkey groups, part of a long-studied population in the Kakamega Forest, Kenya. Observations will include participation in between-group aggression, within-group grooming, and feeding tolerance. The team will use the data to evaluate whether females reciprocate cooperation of different behavioral types. For example, do females who participate often in territorial defense receive grooming, or tolerance at feeding sites, from their groupmates more readily than females who participate less often? Do females who develop good reputations by participating more often in territorial defense or grooming receive cooperation more readily when they request it? Evolutionary studies of behavior focus on the costs and benefits of different behavioral programs. While receiving reciprocated cooperation is one benefit of cooperating, theory suggests other potentially important factors. The research will also investigate how cooperation is related to personal risk, in relation to physical and reproductive condition, and the degree to which partners are relatives. Kin selection theory predicts that cooperation will be nepotistic. Pedigree records and genetic analyses will allow evaluation of both maternal and paternal kinship, and the predictions of kin selection theory will be tested with behavioral data. Fieldwork will thus include collection of fecal samples, from which DNA is extracted for paternity analysis. The DNA analysis, including development of several new markers, will be carried out under the supervision of co-PI Todd Disotell,. Studying the effects of paternal kinship is a new focus in investigations of social cooperation, and the project will provide valuable comparative data on the degree to which paternal kinship drives social behavior. Broader impacts of the study include training of American and foreign students, both graduate and undergraduate, as well as a post-doctoral researcher. International collaboration with a Kenyan university will also be facilitated. The PI's longterm presence at the field site will continue to contribute to rainforest conservation strategies through a local community-based conservation education program.