Swarm sense

Just a few bees may be able to direct a swarm according to a researcher at Oxford University, UK. Iain Couzin developed an algorithm that shows how simple animals can use simple rules to make complex group decisions. Only a few animals need to know what they should be doing, and, as the group gets larger, the proportion of clued-up animals actually falls.

The algorithm gives its virtual animals several rules of thumb. One is that they try to avoid becoming cut off from the crowd. ... Another rule is that group members should avoid getting so close that they crash into one another.

In addition to these opposing forces, the virtual animals are given a power of persuasion that depends on their desire to lead the group in a specific direction. Completely naive animals, with no idea of where to go, have zero power.

The simulations show that even when naive and informed individuals cannot recognize one another, the novices spontaneously respond to decisions by the experts, because they follow their tendency to stick with the group.