Meeting Abstract
P3.117 Saturday, Jan. 5 Effects of incline and surface width on the climbing performance in crevices versus on cylinders of corn snakes (Elaphe gutatta) ASTLEY, H.C.*; JAYNE, B.C.; University of Cincinnati; University of Cincinnati astleyhc@email.uc.edu
One presumed advantage of a limbless body plan is the ability to fit in laterally restricted spaces, such as branches in arboreal habitats or tunnels. Although many snake species climb proficiently, the effects of incline on the locomotion of snakes are poorly understood despite the ecological relevance of how inclines affect whether gravity facilitates or impedes movement. Thus, we tested the effects of incline on snake locomotion by quantifying maximal speeds of movement and the kinematics of four similar-size adult corn snakes ascending and descending vertical, 45 degree and horizontal cylindrical perches and tunnels. We used seven diameters of perches and widths of tunnels ranging from 2-20% of the average snout-vent length of the snakes. The ability to move on increasingly steep inclines decreased with increased diameter for both perches and tunnels. In both tunnels and perches, snakes descended using a controlled slide, whereas for horizontal and ascending movement snakes used different types of concertina locomotion. Movement in tunnels was substantially faster than on perches with similar incline and width. Speed decreased with increased incline for both tunnels and perches. Velocity was unaffected by tunnel width but decreased significantly with increased perch diameter. Despite the superficial similarities of constrained lateral spaces and the locomotor modes used, the three-dimensional movements on perches had a profound negative effect on performance. The diminished locomotor performance on horizontal cylindrical perches compared to tunnels may arise from the difficulty of maintaining balance, and the complicated three-dimensional axial bending may reduce the amount of axial muscle that can contribute effectively to forming anchor points.
