ABSTRACT P.I. John Fleagle/Pierre Lemelin SBR- 9318750 The evolution of prehensile extremities is a recurrent theme in models of primate origins. However, there is strong disagreement about the underlying causes associated with the shift toward greater prehensile capabilities of the hand in primates. Proponents of the arboreal theory of primate origins have suggested that locomotion in the trees, especially leaping from branch to branch, was the primary selective factor involved in the evolution of prehensile hands and other primate diagnostic features. Alternative models stressing viual predation on invertebrates on fine-branch supports have also been proposed to explain the emergence of these features. The main problem when evaluating these models is that no detailed knowledge exists on how performance variables actually relate to hand function and structure in extant primates. To this end, this research project will document associations between hand morphology and hand use during locomotion, posture, and manipulation of food objects whithin extant prosimian primates. Differences in hand proportions and musculature will be contrasted with behavioral observataions on hand use for selected genera. Comparisons will then be made with some non-primate groups in order to highlight the peculiarly primate specializations of prehensility. This study will provide an empirical basis to evaluate various models of primate origins to explain manual prehensility, and to interpert behavior in many important fossil hands. *** Panthrojfried9318750.abs ! ! ! D ; ; ( Times New Roman Symbol & Arial " h % % = Jonathan Friedlaender Jonathan Friedlaender
