Fig. 2. Conditioned taste aversion (CTA) in snails. The numbers of bites min^–1 elicited by the CS [the conditional (taste) stimulus] in the test session following training. (A) Sucrose was used as the CS. The CS-elicited feeding response following training in CTA-trained snails (N=40) was significantly less (*P<0.01, one-way ANOVA followed by the post hoc Scheffé test) than in either snails given backward-conditioning (N=35) or naive (N=39) snails. Further, there was no significant difference in the elicited feeding response between the backward-conditioned group and the naive group. (B) Carrot juice was used as the CS. The data are plotted as in A, and similar results were obtained. The numbers of snails were as follows: 45 naive snails, 35 backward-conditioned snails, and 63 conditioned snails. All data are means ± s.e.m.