When honeybee, Apis mellifera, swarms lift off to fly to their new nest site, only a small proportion of
individuals know the location of the new site, yet these few individuals must guide the entire swarm to
the correct place. How do scouts transfer directional information to their swarm-mates? The vision
hypothesis proposes that scout bees fly rapidly through swarms ‘pointing’ in the direction of travel. We
examined the vision hypothesis by exposing flying swarms to a large number of fast-moving bees headed
in the wrong direction. These bees mimicked scouts and created conflicting directional information.
Swarms that were exposed to conflicting information from fast-moving bees showed clear evidence of
disrupted guidance including splitting and failure to reach the nestbox. We discuss the implications of
our findings for hypotheses about the mechanisms of swarm guidance, and for our knowledge of how
collectively moving groups deal with conflicting information.
2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.