Naturalistic Behavior: Introduction A.L. Rosenberger. Methodological Issues in Studying Positional Behavior: Meeting Ripley's Challenge M. Dagosto, D. Gebo. Qualitative Differences in the Positional Behavior of Pithecia Pithecia and Chiropotes Satanas S.E. Walker. Patterns of Suspensory Feeding in Alouatta Palliata, Ateles Geoffroyi, and Cebus Capucinus D. Bergeson. Morphology and Behavior: Introduction J.G. Fleagle. Reconstruction of Hip Joint Function in Extant and Fossil Primates L. MacLatchy. Grasping Performance in Saguinus Midas and the Evolution of Hand Prehensility in Primates P. Lemelin, B.W. Grafton. Data Acquisition and Analytic Techniques: Introduction E. Strasser. Advances in 3-Dimensional Data Acquisition and Analysis J. Kappelman. Laser Scanning and Paleoanthropology: An Example From Olduvai Gorge, Tanzania L.C. Aiello, et al. Fossils and Reconstructing the Origins and Evolution of Taxa. Introduction H.M. McHenry. Afropithecus, Proconsul and the Primitive Hominoid Skeleton C. Ward. Fossil Evidence for the Origins of Terrestriality Among Old World Higher Primates M.L. McCrossin, et al. 14 Additional Articles. Index.