Figure 6. Average angular velocity as a function of stimulation frequency for six motion types.

(A) protraction/retraction, (B) levation/depression, and (C) extension/flexion elicited at stimulation frequencies ranging from 20 to 300 Hz at a step increment of 20 Hz at frequencies less than 100 Hz and at a step increment of 50 Hz at frequencies greater than 100 Hz. The different colors of dotted lines indicate different beetles used in the experiments. The thick black line represents the mean value of the average angular velocity (absolute values used for all the motions) at various stimulation frequencies (number of beetles  = 5, number of data points at each stimulation frequency  = 25 for each motion type).