The mathematics of fish schools and flocks of humans

This non-technical article looks at Professor Ian Couzin’s work on how a group of individuals make decisions about how to move and where to go all at once?

Similar to Boids, he found that motion for any individual entity as governed by three factors: a short-range repulsive behavior (don’t run into each other), an intermediate range desire to align with neighbors, and a long-range attraction to the group as a whole.

Adding only one or two more rules to the three, he was able to show how schools of fish avoid predators and identify the fastest way to evacuate a school gym (just tell a few individuals to head to specific exits ahead of time).

What looks chaotic and complex at first glance can be explained, at least partially, by a simple set of rules.