Fig. 2. Representative kinematic profiles of right hindlimb joints for river cooter turtles (P. concinna) during a walking step over a force platform. Top to bottom: femoral (hip) protraction (Pro.)/retraction (Ret.) angle, femoral (hip) abduction (Ab.)/adduction (Add.) angle, knee angle and ankle angle (Ext., extension; Flex., flexion). Kinematic profiles represent mean (±s.e.m.) angles averaged across all four turtles (N=18–21 trials per individual, 78 total steps per data point). Note that axis scales differ for these plots to provide increased resolution for smaller angles.