Preference indices of the wild-type (Canton-S;CS) and the DopEcRGAL4 mutant male flies in a two-choice CAFE assay using 5% sucrose solution and 5% sucrose solution supplemented with copper. The copper concentration is indicated on the left. n= 7, 7 for CS and DopEcRGAL4, respectively. Ns:p> 0.05, *p< 0.05. ***p< 0.001. Mann-Whitney U test is used. See also Figure S1 for the control experiments.
