Fig. 3. Flies show similar responses to individual elements of the expansion/contraction pattern. Data (including scale bar) presented as in Fig. 1. (A) Mean responses to full-field expansion/contraction. (B) Responses to a pattern of translation without motion in the lateral fields of view produce expansion avoidance responses similar to the full-field pattern. (C) Responses to the focus of expansion and (D) contraction. For comparison, assuming bilateral symmetry, data from Fig. 1C are inverted and re-plotted here (inset). The sum of the responses shown in C and D (dotted red line in A) approximates full-field expansion/contraction responses (N=10).