Fig. 2. Duty factor (the proportion of a stride cycle for which a given limb is in contact with the ground) of treadmill trials for (A) walking D. rotundus, (B) bounding D. rotundus and (C) M. tuberculata. Blue circles represent the means of left and right forelimbs in each trial, and red squares the means of hindlimbs. Each plot includes a horizontal line at duty factor=0.5, the kinematic separation point between walks (duty factor >0.5) and runs (duty factor <0.5) (Hildebrand, 1976).