Fig. 4. Comparison between crayfish that stopped and crayfish that tail-flipped in response to shadows. (A) Approach time, i.e. time to reach the bath electrodes after the experiment was started, does not differ between animals that later stopped or tail-flipped when exposed to shadows. Mann–Whitney test: P0.7. (B) Patterns of positions inside the tunnel for animals that later stopped or tail-flipped when exposed to shadows are not significantly different. Chi-squared test: P0.3. (C) Body orientation does not differ significantly between animals that later stopped or tail-flipped in response to shadows. Mann–Whitney test: P0.6. (D) The locations in the tunnel (past the bath electrodes) are not significant different between animals that later stopped and animals that later tail-flipped to the shadows. Mann–Whitney test: P0.4.