Fig. 1. Seismic rev displays of Schizocosa stridulans. (A) Bout of rev displays. (B) Detail from red box in A. Top panel (i) shows body positions, with letters (a–d) illustrating movements of the palpal tibio-cymbial joint and abdomen. Middle panels (ii) show the oscillogram of rev displays. Bottom panels (iii) show a spectrogram of rev displays. Panels are shown in the same time scale, with letters (a–d) corresponding to the body movements illustrated in i. Signals begin with a flexion of the palpal tibio-cymbial joint (b–c) followed by abdominal vibrations (c–d). Palpal movements correspond to the production of high frequencies, and abdominal movements correspond with the production of low frequencies.