Figure 3.

Shape and its causation in fish schools. (a) Shape (length/width) of the school in the movement direction in relation to cruise speed and number of members of the school (median and interquartile) [15]. Filled circles denote fast speed; open circles denote slow speed. (b) An example of emergence of oblong shape by avoidance of collisions through slowing down (for explanation, see text). (c) Empirical data of length/width (median and interquartile) of schools of 10–60 mullets in the wide passage of a ring-shaped tank [28]. Grey dashed line indicates shape with length/width = 1 (above this value shape is oblong).