Relative effect of ‘attraction’ and ‘alignment’. The figures represent the average turning angle of the focal individual in response to the direction (θ) and relative bearing (ϕ) of the neighbour, limited to situations in which the neighbour is in the attraction zone (at a distance r>5 a.u.). Values of θ close to zero indicate that the neighbour is in front of the focal individual, with positive values indicating that the neighbour is on the right and negative values indicating that the neighbour is on the left of the focal individual. Positive values along the alignment axis ϕ indicate that the neighbour is oriented to the right, with respect to the focal individual, while the two individuals are aligned for values of ϕ close to zero. (a) Condition in which the two particles fly in a front-back configuration. (b) Particles flying side by side; (c) Same condition as (a), but with increased temporal autocorrelation of noise around the target position (C
=100 steps, while it was C
=20 steps in the previous plots). (d) Same as (b), with increased temporal autocorrelation of noise.