Male Allocare in Rhinopithecus bieti at Xiaochangdu, Tibet: Is It Related to Energetic Stress?

西藏小昌都黑白仰鼻猴的雄婴照料:能量胁迫导致?(英文)

Male allocare among nonhuman primates has frequently been investigated from the perspective of the caretaker. Here we examined whether male allocare relates to environmental factors or the females＇ energetic stress. We researched the possible differences of allocare between sexes in free-ranging black-and-white snub-nosed monkeys （Rhinopithecus bieti） in Tibet. A combination of stepwise least squares regression analysis was used to identify the influence of ecological factors （temperature, rainfall, etc.） and infant age that best account for seasonal variation of allocare. The results indicate, except for the functions of infant age, however, that male allocare is a negative function of temperature and female allocare is a positive function of temperature. Specifically, we tested the energetic stress hypothesis, which predicts that the energetic burden of females in a severe environment favour an increased rate of male allocare during the seasons of high energetic stress. We analyzed the allocare difference between high energetic stress season （Mar - Apr）, when temperature was low, food availability was scarce, and infants were young, and low energetic stress season （Jun - Aug）, based on data obtained during June 2003 - June 2004. Our results supported the energetic stress hypothesis because male allocare in high energetic stress season was higher than that of in low energetic stress season and female allocate was reverse. Therefore, we propose it is the energetic stress on female that make male allocare possible. Male take these interests for other aims and meet some functional hypothesis, which are addressed from the perspective of the male.

雄猴照料婴猴行为通常都是从雄猴的角度来分析该行为具有何种适应功能,很少有研究关心为什么雌猴会让雄猴参与照料活动。该文通过西藏小昌都黑白仰鼻猴群的系统观察取样,采用回归分析雄婴照料行为季节变动与婴猴年龄及生态因子(环境温度、食物供应)之间的关系,试图分析是否由于能量胁迫导致雌猴让雄猴参与照料活动,并通过分析高能量胁迫季节(环境温度低、食物缺乏,婴猴年幼需要雌猴携带多)与低能量胁迫季节(环境温度高、食物丰富,婴猴年长需要雌猴携带少)雄婴照料行为差异检验了能量胁迫假说。结果表明雄婴照料行为与温度呈负相关函数,而雌猴照料婴猴行为与温度呈正相关函数;在高能量胁迫的季节,雄猴参与照料行为多,而在低能量胁迫的季节雄猴照料行为少。因此,作者认为是能量胁迫迫使雌猴放弃部分照料婴猴的机会,雄猴利用照料机会获得了其他利益。