Fig. 5. (A) Threshold phonoresponse curves of C. tenera (N=9, for all graphs) to stimulus pulses of constant and variable duty cycles as a function of stimulus pulse periods. (Top) Pulse duration of 2 ms and variable duty cycles; (middle) constant duty cycle of 7% and variable pulse durations; (bottom) constant duty cycle of 20% and variable pulse durations. (B) Habituation/generalization (H/G) trials using equal duty cycles (7%) and search versus attack (terminal phase) echolocation pulse durations (15 and 1.5 ms, respectively) and periods (215 and 21.5 ms, respectively) played in normal and reversed sequence [simulations modelled after field recordings of wild Eptesicus fuscus hunting in an open area (Surlykke and Moss, 2000)]. Values are means + 1 s.d., sample sizes in parentheses.