Meeting Abstract

100.6  Sunday, Jan. 6  The effect of substrate diameter and incline on locomotion in arboreal frogs HERREL, A.*; PERRENOUD, M.; ABDALA, V.; MANZANO, A.; POUYDEBAT, E.; CNRS anthony.herrel@mnhn.fr

Frogs are characterized by a unique morphology associated with their saltatory lifestyle. Yet, arboreal species show morphological specializations relative to other ecological specialists allowing them to hold on to narrow substrates. Here we study the limb and brain morphology in arboreal frogs of the genus Phyllomedusa. In addition, we quantified the 3D kinematics of forelimb movement for frogs moving across branches of different three diameters (1, 4, 40mm) and two different inclines (horizontal and 45 degrees). Our data show anatomical differences between arboreal species compared burrowing, terrestrial and aquatic species in the forelimb anatomy and the size of the cerebellum. Moreover, our results show that grip types differed across diameters and inclines. The kinematics of the wrist, elbow and shoulder as well as the body position relative to the substrate showed significant effects of individual, diameter and incline. Kinematic differences involved the durations, velocity of movement and angular excursions with differences being more pronounced for the distal joints. Interestingly, the effects of diameter and incline on both grip type and kinematics are similar to what has been observed previously for primates suggesting. Thus the mechanics of narrow substrate locomotion appear to drive the kinematics of movement independent of morphology and phylogeny.