Department of Psychology, Hunter College of the City University of New York, New York, New York, USA.
Center for Human Evolutionary Studies, Rutgers University, New Brunswick, New Jersey, USA.
Am J Primatol. 2021 Oct;83(10):e23327. doi: 10.1002/ajp.23327. Epub 2021 Sep 6.
Caring for infants involves lactation, protection, provisioning, and carrying-all energetically taxing states for primate mothers. Holding and carrying clinging infants often constrains mothers from moving and traveling, potentially reducing their food and energy intake; however, when separated from its mother an infant is at risk of predation. This separation therefore requires that mothers be vigilant, further deterring them from feeding. Allomaternal care (AMC) is hypothesized to allow mothers to safely detach from their infants to feed, permitting them to increase energy intake, which is particularly needed for lactation. We examined the nutritional benefits of AMC in black-and-white colobus monkeys (Colobus guereza) by estimating energy intake by lactating mothers during AMC versus non-AMC. We studied seven mother-infant dyads in three groups of C. guereza during six months in Kibale National Park, Uganda. Immature group members handled infants more often than adults, and females handled infants more often than males. An infant's distance to its mother and its nearest neighbor's age and sex best predicted the occurrence of AMC. Lactating mothers fed more often, fed and rested for longer durations, and consumed more metabolizable energy during AMC compared to when they were caring for their infants. These results demonstrate that AMC in C. guereza provides mothers with feeding opportunities that increase their energy intake.
照顾婴儿涉及哺乳、保护、供应和携带——这些都是对灵长类动物母亲能量消耗极大的状态。抱着和携带紧贴着的婴儿常常限制了母亲的行动和旅行，可能会减少她们的食物和能量摄入；然而，当婴儿与母亲分离时，它就有被捕食的风险。因此，这种分离要求母亲保持警惕，进一步阻止她们进食。被照顾的婴儿（AMC）被假设为允许母亲安全地与婴儿分离去进食，使她们能够增加能量摄入，这对哺乳期来说尤为重要。我们通过估计在 AMC 和非 AMC 期间哺乳期母亲的能量摄入，来研究黑猩猩（Colobus guereza）中的 AMC 的营养益处。我们在乌干达基巴莱国家公园研究了 7 对母婴对和 3 组 C. guereza 的 6 个月时间。未成熟的群体成员比成年人更频繁地照顾婴儿，女性比男性更频繁地照顾婴儿。婴儿与母亲的距离以及其最近邻居的年龄和性别最好地预测了 AMC 的发生。与照顾婴儿时相比，哺乳期母亲在 AMC 期间更频繁地喂食，喂食和休息的时间更长，并且消耗更多可代谢能量。这些结果表明，在 C. guereza 中，AMC 为母亲提供了增加能量摄入的喂养机会。
