Mishra Partha Sarathi, Pal Arijit, Velankar Avadhoot D, Kumara Honnavalli N, Singh Mewa, Cooper Matthew
Conservation Biology Division, Sálim Ali Centre for Ornithology and Natural History, Tamil Nadu, Coimbatore, 641108, India.
Bharathiar University, Tamil Nadu, Coimbatore, 641046, India.
Primates. 2020 May;61(3):443-453. doi: 10.1007/s10329-020-00807-4. Epub 2020 Feb 27.
Primates maintain social bonds with specific individuals in the group by directing grooming toward them. Social grooming is often targeted toward individuals with whom the most benefits can be exchanged, which are usually the high-ranking individuals. We used the Seyfarth model to investigate whether dominance rank alters the distribution of grooming in a group of Macaca fascicularis umbrosus at Great Nicobar Island. We investigated whether dominance rank predicted grooming rate in both males and females. We used social network analysis to examine whether high-ranking animals maintain a central position in the grooming network. We also investigated whether adult individuals exchange grooming for social tolerance, as indicated by physical proximity. We found that more social grooming was directed toward high-ranking females, but not high-ranking males. Social network analysis suggested that high-ranking animals are not central individuals in the distribution of grooming; rather, middle-ranking animals were major contributors to the distribution of grooming. There was no relation between the grooming rate and proximity in both males and females. Overall, our findings suggest that females prefer to direct grooming toward high-ranking partners, although the dominance hierarchy is less steep than expected for Macaca fascicularis. Thus rank-related grooming patterns may be a relatively conserved trait in this isolated island population.
灵长类动物通过对特定个体进行梳理毛发来维持群体内的社会联系。社交性梳毛通常针对那些能与之交换最多益处的个体，这些个体通常是地位较高的个体。我们使用塞弗斯模型来研究在大尼科巴岛的一群暗色猕猴中，优势等级是否会改变梳理毛发行为的分布情况。我们研究了优势等级是否能预测雄性和雌性的梳理毛发频率。我们运用社会网络分析来检验地位高的动物在梳理毛发网络中是否占据中心位置。我们还研究了成年个体是否会通过身体接近程度所表明的社交容忍度来交换梳理毛发行为。我们发现更多的社交性梳毛行为是针对地位高的雌性，而非地位高的雄性。社会网络分析表明，地位高的动物在梳理毛发行为的分布中并非处于中心位置；相反，中等地位的动物是梳理毛发行为分布的主要贡献者。雄性和雌性的梳理毛发频率与接近程度之间均无关联。总体而言，我们的研究结果表明，尽管优势等级不如预期的暗色猕猴那样陡峭，但雌性更倾向于将梳理毛发行为指向地位高的伙伴。因此，与等级相关的梳理毛发模式在这个孤立的岛屿种群中可能是一个相对保守的特征。
