雄性川金丝猴对雌性的受孕认知与等级识别

社会认知是群居动物适应复杂环境和社会生活能力的体现,致力于理解自身、他人与社会。认知有利于促进利益分配的优化,而行为认知策略则是关注的热点问题。但迄今为止,川金丝猴如何进行社会地位与受孕状态等基础认知尚不清楚。本研究通过投食招引,在个体识别和等级判定的基础上,以栖息于秦岭观音山自然保护区熊猫谷景区的一个半野生川金丝猴群为对象,采用瞬时扫描和焦点动物取样法,观察并收集了猴群中6个一雄多雌单元成年雌雄个体的空间位置、邀配、交配及产仔行为数据,结合食物密度梯度"同心圆"和受孕周期,推测雌性成功受孕的交配时间段,运用配对t-检验统计证实受孕前后雌性的交配实现率差异显著(t=4.527,P=0.001),表现为受孕前雌性邀配行为获取的雄性响应率明显高于受孕后;通过Spearman相关性检验发现,雌性受孕前的交配实现率(R=0.527,P=0.006)及受孕时间(R=0.556,P=0.049)与自身等级均显著正相关,即高等级雌性邀配行为的雄性响应率及与雄性生殖性交配的时间明显高于或早于低等级雌性。结果表明,雄性川金丝猴拥有认知单元内成年雌性受孕状况和等级地位的能力,这种认知能力影响着雄性的性行为方式。

Recognition of female fertilization and social rank by male golden snub-nosed monkeys (Rhinopithecus roxellana)

Social animals possess important cognitive abilities that help them adapt to complex and variable environments, as well as comprehend their position and that of others within their social groups. Identifying which cognitive behavioral strategies are adopted to maximize reproductive benefits and gain access to resources is an important area of study in primatology. To date, however, research on the recognition of social rank and pregnancy status in golden snub-nosed monkeys (Rhinopithecus roxellana) remains poor. Here we investigated the hierarchical relationships and pregnancy cycles of females from six one-male units (OMUs) located within a provisioned group of golden snub-nosed monkeys from the Guanyinshan Nature Reserve in the Qinling Mountains of China. We used instantaneous scan and focal animal sampling to collect data on spatial position and reproductive behavior to clarify the mating period and analyze differences before and after fertilization. We confirmed significant differences in the rates of sexual solicitation success (t = 4.527, P = 0.001) and found that the rate before fertilization was significantly higher than that after fertilization. Results also demonstrated significant positive correlations between rank status and the rate of solicitation success (R = 0.527, P = 0.006) and time of fertilization (R = 0.556, P = 0.049), which were found to be significantly higher and earlier, respectively, in higher-ranked females than in lower-ranked females. This study revealed that males were able to recognize the pregnancy status and rank of females within their OMUs, which affected their own social and reproductive behavior.