Dissertation Research: Socioecology of Spider Monkeys (Ateles geoffroyi panamensis) in Wet Forest

调查物种内行为和生态变异的范围对于理解更广泛的社会适应模式，同时最大限度地减少遗传学的混淆影响至关重要。 通过研究一个物种在几个不同生境中的社会系统，可以看出变异性。 同一物种社会系统的差异可以用不同生境中食物可获得性和分布的差异来解释。 本研究将探讨蜘蛛猴（Ateles spp.）通过在多产的潮湿森林中研究它们，这是一个以前从未被研究过的栖息地。蜘蛛猴是少数几种具有裂变融合社会系统的哺乳动物之一，在这种社会系统中，整个群体很少合并，而是分裂成具有流动性和可变成员资格的亚群。 这些猴子专门吃成熟的水果，他们的社会系统被认为是一种适应，以减少群体内的进食竞争。 蜘蛛猴如何应对环境的波动，以及它们的反应如何在广泛的栖息地中变化，这对社会生态学的广泛范围来说是有用的。 蜘蛛猴的裂变-融合社会系统的流动性允许敏感地检测诸如饮食、食物可用性和分布以及亚群大小和组成等变量如何相互作用。 没有关于蜘蛛猴生活在一大片连续的、多产的、多样的、低地潮湿森林中的长期研究，在那里它们也与一整套潜在的捕食者生活在一起。 生活在这种多产的森林中可能会导致蜘蛛猴种群的摄食竞争相对减少，因此它们的社会系统可能与生活在干燥栖息地的种群不同。 该项目的目标如下：（1）为了检验有关蜘蛛猴的饮食和觅食生态与社会结构和组织的假设，蜘蛛猴生活在一个多样化的潮湿森林中，旱季减少，（2）通过将本研究结果与其他地点的蜘蛛猴研究结果进行比较，更清楚地了解这种灵长类动物在行为和生态方面的变化，（3）首次对蜘蛛猴群体的变化与社会和生态变量之间的关系进行了研究。 该项目具有跨越多个学科的智力价值。 这个项目将是感兴趣的物理人类学家，因为黑猩猩和倭黑猩猩（潘属），我们最亲近的亲戚，是唯一的其他灵长类动物一贯显示裂变融合社会系统一样，蜘蛛猴;比较研究潘和Ateles提供了一个相对独立的遗传学的方法来理解环境的决定因素的裂变融合社会系统。 这个项目将引起生物学家，特别是行为学家和生态学家的兴趣，因为它关注蜘蛛猴的人口统计学，社会行为和生态学之间的关系。

Investigating the range of behavioral and ecological variability within species is crucial for understanding broader patterns of social adaptation while minimizing confounding effects of phylogeny. Variability may be seen by studying the social system of one species in several different habitats. Differences in social systems within the same species may be explained by differences in food availability and distribution across different habitats. This project will investigate social system variation of spider monkeys (Ateles spp.) by studying them in productive, wet forest, a habitat where they have never before been studied. Spider monkeys are one of only several mammalian species that has a fission-fusion social system, in which the entire group rarely coalesces but instead is split into subgroups with fluid, variable membership. These monkeys specialize on eating ripe fruit, and their social system has been suggested to be an adaptation for reducing feeding competition within the group. How spider monkeys respond to fluctuations in their environment, and how their responses vary across a wide range of habitats, is informative for the broad scope of socioecology. The fluid nature of spider monkeys' fission-fusion social system allows sensitive detection of how such variables as diet, food availability and distribution, and subgroup size and composition interact. No long-term studies exist of spider monkeys living in a large, continuous tract of productive, diverse, lowland wet forest where they also live with a complete suite of potential predators. Living in this productive forest may result in relatively decreased feeding competition for this population of spider monkeys, so their social system may differ from populations living in drier habitats. The objectives of this project are the following: (1) to test hypotheses relating diet and foraging ecology to the social structure and organization of spider monkeys living in a diverse, wet forest with a decreased dry season, (2) to gain a clearer view of this primate's variation in behavior and ecology by comparing the results of this study with those of published studies of spider monkeys from other sites, and (3) to provide the first investigation of the relationships between subgroup changes and social and ecological variables in a large group of spider monkeys. This project has intellectual merit that spans several academic disciplines. This project will be of interest to physical anthropologists because chimpanzees and bonobos (Pan spp.), our closest living relatives, are the only other primates to consistently display a fission-fusion social system like that of spider monkeys; comparative studies of Pan and Ateles provide a relatively phylogenetically-independent approach for understanding the environmental determinants of the fission-fusion social system. This project will be of interest to biologists, especially behaviorists and ecologists, due to its focus on the relationships between spider monkeys' demography, social behavior, and ecology.