Food Mechanics, Foraging Behavior, and The Evolution of 'Robust' (Cebus apella) and 'Gracile' (Cebus olivaceus) Capuchin Monkeys in Guyana

该项目的目标是比较圭亚那Iwokrama雨林保护区簇毛卷尾猴(Cebus Apella)和垂尾卷尾猴(Cebus Olivaceus)的食物力学和食物加工行为。卷尾猴是一种分布在南美洲中部到南部的新大陆猴子。Cebus属表现出两种不同的形态类型：簇生或“粗壮”型，由单一种和三种非簇生或“纤细”型组成，包括本研究感兴趣的种--牙冠草属。簇状的类型以其更“强壮”和强大的咀嚼系统而闻名。然而，关于不同物种食用的食物的机械特性的差异以及这种差异与卷尾猴解剖结构的关系，人们知之甚少。这项研究的主要目的是收集关于食物准备和加工模式(手工和口头)的物种差异的行为数据，以及关于它们摄取的食物物理性质的详细季节性数据。对现存卷尾猴“粗壮”和“轻柔”物种之间的生态形态差异的研究提供了一个独特的机会来测试有关其他“粗壮”和“轻柔”灵长类动物的摄食生态变异性的问题，例如人类祖先中已灭绝的灵长类动物。这不仅是因为它们与早期类人祖先在咀嚼上的相似之处，还因为它们与类人猿和现代人有一系列广泛的特征，例如婴儿发育缓慢，在各种环境中使用工具，以及除人类以外所有灵长类动物中最大的相对大脑大小。此外，关于食物的机械特性和灵长类的咀嚼系统之间的关系的研究在过去十年中引起了越来越多的兴趣。关于咀嚼形态的差异以及现有水果和种子的机械性能的数据为了解物种在解剖学和摄食生态学上的差异提供了重要的洞察。该项目将通过确定更离散的食品机械类别，并将这些类别与同类灵长类物种之间更细微的形态差异联系起来，来增加这方面的知识。

The goal of this project is to compare the food mechanics, and food processing behavior of tufted capuchins (Cebus apella) and weeper capuchins (Cebus olivaceus) at the Iwokrama Rainforest Reserve, Guyana. Capuchins are New World monkeys ranging from Central to southern South America. The genus Cebus exhibits two distinct morphological types; the tufted or "robust" type consisting of a single species and three species of untufted or "gracile" types, including C. olivaceus, the species of interest to this study. The tufted type is noted for its more "robust" and powerful masticatory system. However, little is known regarding differences in the mechanical properties of foods eaten by each species and how such differences relate to capuchin anatomy. The main objectives of this study are to collect behavioral data on species differences in patterns of food preparation and processing (manual and oral), and detailed seasonal data on the physical properties of the foods they ingest. The study of ecomorphological distinctions between "robust" and "gracile" species of extant capuchin offers a unique opportunity to test questions concerning variability in the feeding ecology of other "robust" and "gracile" primates such as extinct primates in human ancestry. This is due not only to the masticatory similarities they share with early human-like ancestors, but also to the broad set of features they share with great apes and modern humans, such as slow infant development, tool-use in various contexts, and the largest relative brain size of any primate except humans. In addition, research concerning the relationship between the mechanical properties of foods and the masticatory systems of primates has seen growing interest over the last decade. Data on differences in masticatory morphology and on the mechanical properties of available fruits and seeds have provided critical insight into species-specific differences in anatomy and feeding ecology. This project will add to this knowledge by identifying more discrete mechanical categories for foods, and by relating these categories to more subtle morphological differences between congeneric primate species.