Fig. 2. Leg force as a function of displacement amplitude and oscillation frequency (blue line, 0.25 Hz; green line, 12 Hz; red line, 40 Hz). (A) Fixed coxa with small-amplitude oscillations (0.1 mm shown) resulted in nearly linear hysteresis loops. (B) Free coxa with small-amplitude oscillations (0.1 mm shown) showing near-linear hysteresis loops. (C) Fixed-coxa oscillations with large amplitudes exceeding 0.3 mm (1.0 mm shown) resulted in hysteresis loops with pronounced non-linearities. (D) Free-coxa oscillations with large amplitudes exceeding 0.3 mm showing non-linearities. The relatively larger areas of the loops in the free-coxa preparation (B,D) compared with the fixed-coxa legs (A,C) show the decreased resilience of a leg with a freely rotating coxa.