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Meeting Abstract
Because three-dimensional structure has long been recognized as an ecological driver of diversity, studying the ways in which animals physically navigate complex environments is paramount to the study of evolutionary transitions. Arboreal locomotion in particular has been understudied from a mechanistic standpoint, despite its role in the radiation and diversification of several vertebrate lineages. Locomoting vertically likely represents a substantial mechanical challenge contingent on interaction with the substrate. We focused on two types of substrate interactions – grasping and friction – in small parrots climbing instrumented ladder rungs. ATI nano-17 six-axis load cells enabled force and torque measurements in all three planes, and biplanar X-Ray video at 250 fps facilitated 3-D kinematics. We found an unexpected influence of the head and neck on upward locomotion and a considerable role of friction on torque application that is dependent on rung diameter.