Triadic male-infant-male interaction serves in bond maintenance in male Assamese macaques

While the ultimate consequences of social bonds start to be better understood, the proximate behavioural mechanisms underlying the formation and maintenance of these close affiliative relationships have received less attention. We investigated the possible function of male-infant-male interactions (MIMIs) in male-male social bonding processes by analysing about 9000h of focal animal observations collected on two groups of wild Assamese macaques. In support of an agonistic buffering function of MIMIs, after engaging in a MIMI upon approach, subordinates stayed longer in close proximity of a dominant male. Overall, the frequency of MIMIs increased the stronger the affiliative relationship between two males, suggesting that MIMIs like grooming function in relationship maintenance. We did not find support for a role of MIMIs in bond formation as the frequency of MIMIs did not affect the time a male dyad spent in proximity in the consecutive year. Our results contribute to the general debate on behaviours influencing social dynamics in group living mammals.尽管人们对社会联结的终极效应已有愈发深入的认知，但这些亲密亲和关系形成与维持背后的近缘行为机制却较少受到关注。本研究通过分析两组野生阿萨姆猴（Assamese macaque）的约9000小时焦点动物取样法（focal animal observation）数据，探究了雄-婴-雄互动（male-infant-male interactions, MIMIs）在雄性间社会联结过程中的潜在功能。研究结果支持MIMIs的对抗性缓冲功能：当从属雄性主动靠近优势雄性并发生MIMI后，其会在优势雄性附近停留更久。总体而言，雄性间的亲和关系越强，MIMIs的发生频率越高，这表明MIMIs如同理毛行为一般，可用于维持社会联结。我们未发现MIMIs参与社会联结形成的证据：MIMIs的发生频率并未影响雄性二元组在次年的共处时长。本研究结果为探讨群居哺乳动物中影响社会动态的行为这一通用学术议题提供了新的实证支撑。