Fig. 4. Effect of dominance status on mean amplitude ratio (error bars ± 1 S.E.M.) of freely interacting female–female (A), male–male (B) and mixed-sex (C) pairs of G. petersii (N=5 fish per group). Amplitude ratios increased in male and female pairs, with the highest amplitude ratios occurring during interaction. Dominant fish showed a trend of increasing amplitude ratio across manipulation periods. The horizontal bar spanning days 4–8 represents the duration of interaction.