Exemplary phonotactic movement of the test animals on the trackball in response to the calling song of the cicada O. rimosa with different intensities. A. schematic oscillogram of the sound track, with a sequence of calling songs (CS) of 10 s and pauses of 2 s with increasing sound pressure levels after the first sequence. The sound pressure levels of 80, 50, 56, 62, 68, 74 and 80 dB SPL, respectively, at the trackball is indicated. B, C. Recordings of the velocity of the trackball rotation by the test animal. The black line represents the instantaneous velocity and the red curves represents a moving average of 20 data points. The fly E. auditrix reacted strongly to the CS, starting at 62 dB SPL (B). The cicada O. rimosa also reacted to the calling songs with 62 dB SPL and higher, but with a lower velocity than the fly (C).