Fig. 5.

Phonotaxis to overlapping sources with small onset time differences (5- and 0.2-ms onset delay). Two synthetic sound sources broadcast with a 5-ms onset delay to produce half-overlapping sound pulses (Inset, A and B), or a 0.2-ms onset delay to produce overlapping stimuli out of phase by 1 cycle of the 5-kHz carrier frequency. (A) Average walking responses (square symbols, 5-ms onset delay; circular symbols, 0.2-ms onset delay) of flies to sources spatially separated by 90° (n = 10 flies). (B) Average walking responses of flies to sources spatially separated by 180° (n = 10 flies). Symbols and horizontal/vertical projections from symbols indicate the mean and confidence intervals of the location of flies at 0.07- (A) and 0.03-s (B) intervals. Filled symbols indicate walking responses to forward (A) or left (B) leading sources while open symbols indicate walking response to lateral (A) or right (B) leading sources. Small onset time differences between sources (0.2 ms) allowed flies to resolve source location ambiguity to the leading source.