Rotational Flocking with Spontaneous Directional Changes

Figure 1

Trajectories and the distributions of the systematic spin. (a) Trajectories of ten pigeons in flock . Each trajectory lies approximately on a plane. (b) Probability distributions of the systematic spin from C.C.W. turning to C.W. turning and (c) the reverse case. It is observed that the spontaneous changes of rotational directions follow a symmetric distribution.

(a)

(b)

(c)