关键词: 滇金丝猴, 相互理毛, 卫生功能假说, 社会功能假说

Abstract: Allogrooming,a common behavior in primates,can reveal hygienic function and the nature of social relationships in gregarious animals.The Yunnan snub-nosed monkey (Rhinopithecus bieti )lives in groups which may number in the hundreds of individuals. Though patterns of allogrooming are important in understanding the social structure of R. bieti, research on the behavior is lacking for this species. From October 2012 to June 2013,we observed allogrooming behavior among females of a provisioned group of R. bieti via all-occurrence sampling and focal animal sampling. We recorded grooming position,grooming posture,and the duration and frequency of allogrooming bouts in Baimaxueshan National Nature Reserve. The mean grooming time was 5.7 min per bout. Female monkeys spend more time grooming the body parts that individuals normally cannot reach on their own (61.1% ),and that mean bout duration is 9.7 min. When grooming parts that a monkey can reach by itself,the mean time drops to 3.2 min. Female monkeys frequently sit face-to-face when they are grooming (48.4%),and the grooming time differed significantly among all grooming postures. Immigrant females usually groomed other members of their one-male unit,more so than they were recipients of grooming. The dissimilarity of allogroomingpositions,postures,and bout durations among female monkeys supports hygienic and social function hypotheses.

Key words: Allogrooming, Hygienic function hypothesis, Social function hypothesis, Yunnan snub-nosed monkey