Fig. 7. Recovery from adaptation to salicin. At the beginning of the experiment (i.e. time 0 h), we measured the caterpillars’ ingestive response (during the 2 min biting test) to the salicin (157 mmol kg^–1) diet. We calculated three ingestive parameters over the 2 min biting test: total intake, total number of bites and bite size. If the caterpillars exhibited an aversive response, we placed them on the salicin diet for 48 h. After this exposure period (i.e. at 48 h), we measured their ingestive response to the salicin diet a second time. If they had adapted to this diet (i.e. did not exhibit an aversive response), we offered them either the salicin diet (A–C) or the control diet (D–F) for an additional 24 h. We called this latter exposure period the ‘recovery phase’. Finally, we measured the caterpillars’ ingestive response to the salicin diet for a third time (i.e. at 72 h). To determine whether the caterpillars’ aversive response to salicin changed during the recovery phase, we made paired comparisons between the ingestive responses at 48 and 72 h using the Wilcoxon matched-pairs signed-rank test (*P0.05).