image H.Chaté, F.Raynaud, STARFLAG Project, CNR-INFM

In 1986 Craig Reynolds devised the boids-algorithm, based on a model of the interactions in flocks, herds or schools of animals. The magic of the boids algorithm is that complex overall patterns emerge from local interactions between agents. Reynolds writes: “flocking requires that it reacts only to flockmates within a certain small neighborhood around itself. The neighborhood is characterized by a distance (measured from the center of the boid) and an angle, measured from the boid’s direction of flight. Flockmates outside this local neighborhood are ignored.”
Recently, european researchers have found that starlings do not interact with all neighbours within a certain range, but rather with a fixed number (six or seven) of neighbours, irrespective of their distance. This makes the flocking more robust when there are big changes in density. Please update your algorithms !
(via greythumb, nice article here)