Swarms of bees and brain neurons make decisions using strikingly similar mechanisms, reports a new study in the Dec. 9 issue of Science. In previous work, Cornell University biologist Thomas Seeley clarified how scout bees in a honeybee swarm perform “waggle dances” to prompt other scout bees to inspect a promising site that has been found.
In the new study, Seeley, a professor of neurobiology and behavior, reports with five colleagues in the United States and the United Kingdom that scout bees also use inhibitory “stop signals” – a short buzz delivered with a head butt to the dancer – to inhibit the waggle dances produced by scouts advertising competing sites. The strength of the inhibition produced by each group of scouts is proportional to the group’s size. This inhibitory signaling helps ensure that only one of the sites is chosen. This is especially important for reaching a decision when two sites are equally good, Seeley said.
Previous research has shown that bees use stop signals to warn nest-mates about such dangers as attacks at a food source. However, this is the first study to show the use of stop signals in house-hunting decisions.
Such use of stop signals in decision making is “analogous to how the nervous system works in complex brains,” said Seeley. “The brain has similar cross inhibitory signaling between neurons in decision-making circuits.”
Co-authors Patrick Hogan and James Marshall of the University of Sheffield in the United Kingdom explored the implications of the bees’ cross-inhibitory signaling by modeling their collective decision-making process. Their analysis showed that stop signaling helps bees to break deadlocks between two equally good sites and to avoid costly dithering.
Material adapted from Cornell University.