Student Prize Award Abstract
1996 Poster Paper Honorable Mention

THE FUNCTIONAL ANATOMY OF THE FORELIMB IN Callimico goeldii AND Leontopithecus rosalia: A STUDY USING KINEMATIC AND MORPHOLOGICAL DATA

G.P. Aronsen and W.C. Hartwig
Department of Anthropology, George Washington University, Washington, D.C. 20052, U.S.A.

Videotaped bouts of locomotor behavior in two small- bodied New World Monkeys demonstrate that the bounding patterns of Leontopithecus and Callimico are significantly different. The bounding pattern of Callimico consists of a basic sequence of spinal flexion with all four cheridia positioned under the body, followed by extension of the spine and limbs. The pattern observed in Leontopithecus is a transaxial bound in which the cheridia are aligned along a single plane, and the body and hindlimbs are carried under the forelimbs in a pendulum fashion, with the leading foot overstepping the forelimb. Results from kinematic analysis indicate that Leontopithecus has more acute flexion/retraction at the shoulder, elbow, hip, and knee joints, while Callimico consistently extends the limbs to a further degree at these joints. Osteometric data shows that the forelimb of Leontopithecus is long and relatively gracile compared to Callimico, which is more robust in its postcrania. Specific morphological features of the shoulder and elbow joints of each species correlate with the bounding patterns described above, but derived features of the Leontopithecus radius may relate more to foraging adaptations than locomotion. Relating anatomical features to specific locomotor behavior provides an understanding of the adaptive strategies and evolutionary history of these two primates.