Fig. 1.

a Positions of the focal fish (red dot) relative to its closest neighbour. At negative values, the focal fish was swimming behind its closest neighbour, 0 represents swimming side by side, and at positive values, the focal fish was ahead of its closest neighbour. Note that for clarity, the other six school members are not shown in the figure. b Reduction in TBF (%) of focal fish when swimming in different positions in a school, compared to swimming alone. Bar values refer to the position represented above in panel a. Values are mean ± S.E. c Reduction in the estimated metabolic rate (MO₂) compared to solitary swimming in juvenile golden grey mullet while swimming in various positions relative to a neighbour in a school. Values are mean ± S.E.