Doctoral Dissertation Research: Positional Behavior and Limb Use in Cebus, Alouatta, and Ateles

位置行为（运动和姿势）的研究是生物人类学中关键问题的核心，包括灵长类动物的起源和树栖适应、类人猿攀登和类人猿两足行走。对运动和姿势的研究提供了有关现存物种的生态、解剖和进化关系的重要信息，为解释化石记录提供了比较框架，并作为保护和生态规划的教育工具。本研究考察了哥斯达黎加热带雨林中三种新世界灵长类物种（阿鲁瓦塔·geoffroyi、阿鲁瓦塔·palliata和阿鲁瓦塔·capucinus）的位置行为和肢体和卷尾使用细节的个体发生（个体的生活史）。在成长和发展的过程中，个体在利用环境方面面临着不同的挑战。个体发生数据允许评估行为和形态的变化，因为他们发生和发展限制在密切相关的物种之间的位置行为。虽然个体发生对我们理解位置行为至关重要，但还没有实地研究评估它对新大陆灵长类动物的影响。白面卷尾猴（Cebus）、黑爪蜘蛛猴（Ateles）和披毛嚎叫猴（Alouatta）将在哥斯达黎加的La Suerte生物研究站进行研究。结合数字视频记录的行为观察将用于记录婴儿期、青少年期和成年期的位置策略，以实现以下目标。首先，本研究将对三种卷尾动物的表达行为、功能形态和生态环境进行全面、系统和量化的描述。其次，关于幼鱼和成鱼位置策略的数据将提供关于生长和发育如何影响幼鱼觅食策略、社会行为和最终生存的信息。第三，由于可卷曲的尾巴在Atelinae亚科（Alouatta、Ateles、Brachyteles和Lagothrix）和Cebus亚科中是独立进化的，因此本研究将允许将可卷曲的尾巴作为两个更密切相关的物种（Ateles和Alouatta）的共享衍生特征进行比较，并将其作为更远亲的Cebus的类似特征进行比较。近亲吼猴和蜘蛛猴是ateline主题的生物行为变体，即大型，长尾的新世界灵长类动物，具有广泛的抓握能力。卷尾猴的尾巴也具有抓握能力，但它们的体型和尾巴的解剖结构（以及进化史）不同。该项目将对生活在同一热带雨林的三种新世界灵长类动物的行为和生态环境进行全面、系统和量化的描述。通过关注位置行为的个体发生差异问题，本研究考察了灵长类动物个体发生中类似成人的运动和姿势模式的发展程度，以及这些模式在年龄和性别类别内部和之间的差异。最后，本研究结果将用于La Suerte生物研究站周围雨林的保护规划和维护。作为这些努力的一部分，其成果将有助于周边社区和美国的教育项目。

Studies of positional behavior (locomotion and posture) are central to key issues in biological anthropology including primate origins and arboreal adaptations, hominoid climbing, and hominid bipedalism. The study of locomotion and posture provides critical information concerning ecological, anatomical and evolutionary relationships in living species, a comparative framework for interpretation of the fossil record, and as an educational tool for conservation and ecological planning. This research examines the ontogeny (the life history of an individual) of positional behavior and details of limb and prehensile-tail use in three New World primate species (Ateles geoffroyi, Alouatta palliata, and Cebus capucinus) inhabiting a tropical rainforest in Costa Rica. During the course of growth and development, individuals face different challenges in exploiting their environment. Ontogenetic data allow assessment of behavioral and morphological changes as they occur and developmental constraints on positional behavior among closely-related species. While ontogeny is critical to our understanding of positional behavior, there are no field studies that assess its effects on New World primates. White-faced capuchins (Cebus), black handed spider monkeys (Ateles), and mantled howling monkeys (Alouatta) will be examined at La Suerte Biological Research Station in Costa Rica. Behavioral observations in conjunction with digital video recording will be used to document positional strategies during infancy, juvenescence, and adulthood to address the following objectives. First, this research will provide a comprehensive, systematic, and quantified description of expressed behavior, functional morphology, and ecological context of three prehensile-tailed species. Second, data on juvenile and adult positional strategies will provide information on how growth and development may influence feeding and foraging strategy, social behavior, and ultimately survival during the juvenile period. Third, because the prehensile tail has evolved independently in the subfamily Atelinae (Alouatta, Ateles, Brachyteles, and Lagothrix) and Cebus, this study will allow comparison of the prehensile tail as a shared-derived feature in two more closely-related species (Ateles and Alouatta), and as an analogous feature in the more distantly- related Cebus. Closely-related howler and spider monkeys are biobehavioral variations on the ateline theme, that is, large-bodied, long-tailed New World primates with extensive gripping capabilities. Capuchin monkeys, also with prehensile abilities of the tail, differ in body size and tail anatomy (and evolutionary history). This project will contribute a comprehensive, systematic, and quantified description of expressed behavior and ecological context in three New World primates inhabiting the same rainforest. By focusing on questions of ontogenetic differences in positional behavior, this study examines the degree to which adult-like patterns of locomotion and posture develop in primate ontogeny and how patterns may differ within and between age and sex categories. Finally, the results of this research will be used in the conservation planning and maintenance of the rainforest surrounding La Suerte Biological Research Station. As part of these efforts, results will contribute to educational programs in the surrounding community and in the United States.