Honeybee swarms: how do scouts guide a swarm of uninformed bees?

The organized movement of a swarm of honeybees towards its new home is a perplexing phenomenon because only a small number of scout bees, approximately 5%, know the direction in which the swarm has to move. Nevertheless, in the majority of cases a swarm, comprising about 10 000 mainly uninformed bees, reaches the new home. How do the scouts transfer directional information en route to the uninformed bees? We investigated a hypothesis proposed in the 1950s that suggests that scout bees fly rapidly through the airborne swarm, pointing towards the new home. We developed a model that simulates the movement of swarms and scouts and showed that when scouts fly through the swarm at a speed slightly higher than the speed of the other (uninformed) bees, they are indeed able to direct the swarm towards its new home. Hence, our model strongly supports the proposed hypothesis and shows that a collection of uninformed bees can be successfully guided by the purposeful movements of a small number of informed scouts.