Fig. 5. Mean electric organ discharge (EOD) duration (error bars ± 1 S.E.M.) of freely interacting, restricted interaction and solitary female–female (A) and male–male (B) pairs of G. petersii. Both free and restricted female pairs showed a comparable increasing trend. This trend did not occur in male pairs. The EOD in solitary fish of both sexes remained unchanged. The horizontal bar spanning days 4–8 represents the duration of interaction.