Figure 3.

The results of experiment 3, showing the immediate response of fairy-wrens to synthetic aerial alarm calls varying in both peak frequency (PF) and frequency modulation rate (MR; n = 10 playbacks in each column; raw data shown): (a) the proportion of focal birds fleeing to cover or scanning; and (b) the observed mean (±s.e.) duration (s) the focal bird spent in cover before re-emerging. Natural fairy-wren alarm calls served as a positive control; synthetic calls had fairy-wren base properties (see text). Black bars, fleeing; white bars, scanning.