Fig. 4. Free response recovery times. The time it takes to reach individual displacement maxima in the damped response for both the free-(dark grey) and fixed-coxa (light gray) preparations. Bars represent the mean times ± s.d. (N=10). The average swing duration for B. discoidalis running at its preferred speed is 50–60 ms. The free-coxa preparation recovers 88% of the perturbation by the second maxima and never has a third maxima with less than 95% absorption. The fixed coxa recovers 74% of the perturbation by the second maxima, 90% by the third, and never has a fourth with less than 95% absorption. In all cases the time to each point is less for the fixed-coxa legs (t-test, P<0.0001) and the time to reach 99% absorption is less than the duration of the swing phase (z-test, P<0.0001).