Spider monkeys are one of the most widespread New World primate genera, ranging from southern Mexico to Bolivia. Although they are common in zoos, spider monkeys are traditionally very difficult to study in the wild, because they are fast moving, live high in the canopy and are almost always found in small subgroups that vary in size and composition throughout the day. The past decade has seen an expansion in research being carried out on this genus and this book is an assimilation of both published and previously unpublished research. It is a comprehensive source of information for academic researchers and graduate students interested in primatology, evolutionary anthropology and behavioral ecology and covers topics such as taxonomy, diet, sexuality and reproduction, and conservation.