Fig. 4.

Fictive call stimulus–response trains from a reproductive male housed in 14 h L: 10 h D and tested at night. (Ai–iii) Example of the time- and stimulation-dependent progression of fictive grunts to longer duration calls. Shown here are 20 s excerpts from 40 stimulus trains with stimulus artifacts (S.A., Ai) shown at 1 s intervals followed by the fictive call (see text for details). (Bi–iii) As fictive grunts transition to fictive grunt–hums and duration increases, mean firing frequency (20 calls, one male) decreases. Recording temperature, 16.3°C.