Fig. 7.1

(A?B) Paramecia consumption over 20 min. (A) NTR- fish showed no significant difference between +MTZ or -MTZ-treated groups (two-way repeated measures ANOVA, effect of treatmet p = 0.33). Error bars are SEM. (B) Nitroreductase expressing NTR+/+MTZ fish consume paramecia more slowly than NTR+/-MTZ fish (minute 10: p = 0.036; minute 15: p = 0.040; minute 20: p = 0.051; two-way repeated measures ANOVA, effect of treatment: p = 0.073). (C) Expression of NTR-mCherry in Tg(gng8:Gal4;UAS:NTR-mCherry) fish is specific to the habenula. Image is a maximum intensity projection of a Z-stack, NTR expression is shown in red. Scale bar is 200 µm. (D) The number of paramecia initially added to the wells was not significantly different between the +MTZ and -MTZ-treated groups, for either the NTR+ fish (p = 0.69, left side) or NTR- fish (p = 0.74, right side). Every dot represents one fish, boxplots show median and 25th and 75th percentiles. (E?F) No significant difference in average swim speed between +MTZ and -MTZ fish in NTR+ animals during the 10 min acclimation period before addition of paramecia (E) (p = 0.46) or during the 20 min prey capture period after addition of paramecia (F) (p = 0.29). Dots represent individual fish, boxplots show median and 25th and 75th percentiles. (G) Habenula ablation does not affect paramecia consumption in non-experienced fish. Two-way repeated measures ANOVA shows no effect of treatment, p = 0.37. Error bars are SEM. A permutation test was used for all pairwise comparisons unless specified otherwise (see Materials and methods, Behavioral data analysis and statistics). Data tables for panels A, B, D, E, and F are in Figure 7?figure supplement 1?source data 1.