Larval pheromones act as colony-wide regulators of collective foraging behavior in honeybees

When animals move or forage in groups, collective behaviors arise from independent decisions that individuals make based on limited information about the environment. In decentralized systems in which individuals use local cues to decide how to allocate their time amongst multiple tasks, a "global" signal detectable over large distances by all members of the group could have a profound effect on task allocation and coordination. Honeybees provide a unique opportunity to study how information transfer modulates behavior because they produce pheromones that can regulate the actions of thousands of individuals in a colony. We used electrophysiological and behavioral assays to compare the transmission modes of 2 larval pheromones to test the hypothesis that larval pheromones can act as "global" signals by rapidly regulating behavior throughout a colony without direct physical interactions between individuals. By studying mechanisms of pheromone transmission at the individual and colony level, we provide evidence that larval pheromones act as direct rapid and powerful regulators of behavior, even among individuals too far away from each other to use visual or tactile cues. Therefore, our results suggest that in some cases, global signals can be important regulators of collective behavior.