Meeting Abstract

14.5  Thursday, Jan. 3  The Effects of Substrate Type and Size on the Locomotion of Kinkajous LEMELIN, P*; SCHMITT, D; MACKENZIE, A; GEORGE, G; CARTMILL, M; Univ. of Alberta; Duke Univ.; Univ. of Alberta; Univ. of Alberta; Duke Univ. plemelin@med.ualberta.ca

Kinkajous (Potos flavus) are highly arboreal South American procyonids that show behavioral and ecological similarities with primates and arboreal opossums. Like primates and arboreal opossums, kinkajous use diagonal-sequence (DS) walking gaits, which are rare in other mammals (Hildebrand, 1976; McClearn, 1992). However, the actual frequency of DS gaits and the functional context in which these gaits occur remain unknown. The effect of substrate type and size on the locomotion and gait patterns of kinkajous was examined in the laboratory. Gaits were digitally recorded (60 Hz) in two adult females walking and running on graphite poles of different diameters (16 and 25 mm) and on a wooden runway. Forelimb and hindlimb duty factors, and diagonality (i.e., phase relationship between forelimb and hindlimb on the same side) were calculated for 534 gait cycles. Like primates and arboreal opossums, kinkajous rely mostly on DS gaits during walking, with average diagonalities above 55%. The amble was a common running gait adopted on the runway, which is also typical for primates (Schmitt et al., 2006). These ambling gaits were characterized by relatively low forelimb duty factors compared to the hindlimb. Unlike primates and arboreal opossums, almost identical average duty factors characterized the forelimbs and hindlimbs during locomotion on poles. The fact that kinkajous do not show prolonged hindlimb duty factors relative to the forelimbs during locomotion on poles may be linked to the absence of a grasping foot with a divergent hallux in this procyonid compared to primates and arboreal opossums. Funded by NSERC and NSF BCS-0137930.