Male Cooperation in Primates: Physiological Correlates of Intra- and Intergroup Relations

社会纽带和亲社会行为是包括人类在内的许多灵长类动物的基本特征，但人们对这些行为的进化根源和生理基础知之甚少。该项目将使用两种非人类灵长类动物的激素、能量和行为数据来更好地理解灵长类动物的亲社会行为和雄性合作。这项研究的独特之处在于，它将专门研究与群体内积极的男性社会互动和群体间集体男性攻击有关的潜在生理机制。这一发现将有助于更广泛地理解合作在灵长类动物进化中的作用。该项目将扩大PI对国际合作和教育STEM学生和研究人员的长期承诺。实地部分包括在行为、生态学和保护研究方法方面培训助理，而本研究的实验室部分将为德克萨斯大学的本科生和研究生提供接受现代分子技术培训的机会。通过PI和美国及海外的高级研究人员的公众宣传和保护教育，该项目还将支持全球灵长类动物和栖息地保护工作。该项目为厄瓜多尔Yasuní国家公园的蜘蛛猴（Ateles belzebuth）和长毛猴（Lagothrix poeppiggi）之间雄性社会关系的生理相关性研究申请了为期两年的研究资金。研究人员将结合激素分析和实地观察，以1)描述睾丸激素（T)和糖皮质激素（GCs）的种间和个体间变化，以及对群体内和群体间攻击的行为反应，2）研究这种变化如何受到群体内社会联系强度和群体间竞争强度的影响。蜘蛛和长毛猴的特点是群体内的雄性亲缘关系高，雄性攻击率低。然而，这两个物种之间群体间的攻击模式是不同的：在非人类灵长类动物中，边界巡逻和不同群体的雄性蜘蛛猴之间的攻击相遇是最引人注目的集体攻击例子，只有在一些黑猩猩种群中看到的群体间“战争”可以与之媲美，而长毛猴群体之间的相遇往往更宽容。因此，本研究将开始解开相似生理反应的行为表达如何受到个体与群体水平竞争的不同影响。

Social bonds and prosocial behaviors are fundamental aspects of many primate groups, including humans, yet the evolutionary roots and physiological underpinnings of these behaviors are poorly understood. This project will use hormonal, energetic, and behavioral data for two non-human primate species to better understand prosocial behaviors and male cooperation in primates. The study is unique in that it specifically will examine the potential physiological mechanisms that are associated with positive male-male social interactions within groups and with collective male aggression between groups. The findings will contribute to a broader understanding of the role of cooperation in primate evolution. This project will expand the PI's long-term commitment to international collaborations and educating STEM students and researchers. The field component involves training assistants in methods for behavior, ecology, and conservation research, while the laboratory component of this study will provide opportunities for University of Texas undergraduate and graduate students to receive training in modern molecular techniques. Through public outreach and conservation education by the PI and senior research personnel in both the US and abroad, the project will also support global primate and habitat conservation efforts.This project requests funds for a two-year study to characterize the physiological correlates of male social relationships among spider monkeys (Ateles belzebuth) and woolly monkeys (Lagothrix poeppiggi) in Yasuní National Park, Ecuador. The investigators will combine hormonal analyses with field observations, to 1) characterize interspecific and interindividual variation in testosterone (T) and glucocorticoids (GCs), and behavioral responses to both intra- and intergroup aggression, and 2) examine how this variation is influenced by the strength of intragroup social bonds and the intensity of between-group competition. Both spider and woolly monkeys are characterized by high rates of male-male affiliation and low rates of male-male aggression within groups. However, patterns of aggression between groups differ between these two species: boundary patrols and aggressive encounters between males from different groups of spider monkeys are among the most dramatic examples of collective aggression seen in non-human primates, paralleled only by the intergroup "warfare" seen in some populations of chimpanzees, while encounters between woolly monkey groups are frequently more tolerant. Thus this study will begin to untangle how the behavioral expression of similar physiological responses may be affected differently by individual versus group-level competition.