Figure 1. Prior female experience inhibits sex-related male-male aggression.

(a) Scheme for the aggression assay, four conditions are shown with color coding as naïve male only (blue), experienced male only (purple), naïve male + virgin female (red), experienced male + virgin female (green). (b) Timeline of the average aggression duration of wild-type Canton-S (cs) males within 2 hours. Each data point represents average aggression duration quantified in 5 min intervals. The lack of aggression within the first 30 min reflects courtship behavior. (n = 4 pairs for each condition). (c) Average aggression duration of cs and w¹¹¹⁸ males under different conditions. Both genotypes showed female experience induced inhibition of aggression in pair-or single-housed settings. (n = 11 and 6 for cs and w1118 in pair-housed, 8 and 7 in single-housed). Aggression interactions 60-90 min after the onset were quantified. p <0.0001 (***), =0.019 (*), =0.0084 (**), =0.0059 (**), <0.0001 (***) . (d) The inhibition index, defined as (Aggression^N – Aggression^E) / Aggression^N, for pair- and single-housed settings. (n = 11 and 8 for pair and single.) p = 0.1989. Student's t-test. *: p<0.05, **: p <0.01, ***: p <0.001. Error bars denote s.e.m.