a joint trip, irrespective of the type of conflict, become less responsive to their partners. Recent studies discuss the relationship between initiative and leadership in coordinated group movement [40–42]. Our present results show that, in pairs of foraging sticklebacks, leadership is not simply the outcome of pre-existing individual differences in temperament. Rather, individuals actively gain influence (at least in the short term) by taking the initiative in group movement, just as they can lose influence by hanging back. Furthermore, success in recruiting a partner has an effect in determining an individual’s propensity to initiate future trips, at least for the shyer member of the pair. 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