RAPID Twinning in Monogamous Owl Monkeys of the Argentinean Chaco: Developmental and Behavioral Consequences

灵长类动物的行为中，很少有像雄性对幼崽的悉心照料这样令人着迷却又知之甚少的。在灵长类动物中，没有比猫头鹰猴更广泛的父系关怀了。鸮猴是一种生活在中美洲和南美洲的小型树栖灵长类动物，它们群居生活，只有一只繁殖雄性，一只繁殖雌性。在这些一夫一妻制的群体中，父亲是照顾婴儿的主要提供者，比母亲更多地运送、玩耍、分享食物和梳理婴儿。自1996年以来，阿根廷猫头鹰猴项目一直在评估人类和非人类灵长类动物的社会一夫一妻制、婴儿护理和配对关系的进化假设。为什么雄性猫头鹰猴在一夫一妻制的关系中交配，可能会放弃其他繁殖机会？为什么他们提供这么多的婴儿护理？15年来首次诞生的两对双胞胎，为进一步评估男性在照顾婴儿方面的贡献降低了母亲的精力成本这一假设提供了可能性。在6个月的时间里，本研究将描述两组双胞胎的发展特征，并将描述双胞胎与父母、双胞胎与兄弟姐妹、父母与年长的孩子之间的行为互动。这项研究的结果将用于与多年来在独生子女群体中收集的类似数据进行比较。这项研究将扩大猫头鹰猴项目的广泛影响。作为阿根廷大查科唯一一个针对哺乳动物的长期项目，该项目对保护这一生态系统及其动物群产生了倍增的影响。多年来，来自美国（100名）、阿根廷（120名）和其他14个国家（30名）的200多名学生（52%女性，48%男性）参与了生物人类学的研究，促进了生物人类学的发展。

Few aspects of primate behavior are so intriguing, yet so poorly understood, as the intense care of infants by males. And nowhere among primates is paternal care more extensive than among owl monkeys. Owl monkeys are small, arboreal primates of Central and South America who live in groups with only one reproducing male and one reproducing female. In these monogamous groups, the father is the main provider of infant care, transporting, playing, sharing food and grooming the infant more than the mother. Since 1996, the Owl Monkey Project of Argentina has evaluated hypotheses on the evolution of social monogamy, infant care, and pair bonding in humans and non-human primates. Why do male owl monkeys mate in a monogamous relationship presumably foregoing other reproductive opportunities? Why do they provide so much infant care? The birth of two sets of twins for the first time in 15 years, offers the possibility of further evaluating the hypothesis that males' contribution to infant care reduces the mother's energetic costs. During a 6-month period, this study will characterize the development of the two set of twins and will describe the behavioral interactions between twins and parents, twins and siblings, and parents and older young. Results from this study will be used for comparison with similar data collected over the years in groups with singletons. The study will expand the broad impacts of the Owl Monkey Project. Being the only long-term program on any mammal species in the Argentinean Gran Chaco, the project has multiplying effects on the conservation of this ecosystem and its fauna. It also promotes the development of biological anthropology through the participation over the years of more than 200 students (52% females, 48% males) from the US (100 students), Argentina (120 students) and 14 other countries (30 students).