Queen Bee Pheromones Influence Daughters' Decisions to Stay or Leave

A study published July 28 in Proceedings of the Royal Society B reveals that queen sweat bees of the species Megalopta genalis produce pheromones that signal their reproductive fitness and influence whether their daughters stay to help or leave to reproduce independently. Researchers collected and analyzed waxy surface chemicals from bees on Barro Colorado Island in Panama, identifying methylalkanes as key queen pheromones. These compounds elicited submissive behaviors in workers, suppressed their reproductive development, and altered hormone levels. Higher methylalkane levels correlated with more eggs laid by the queen and more daughters staying home. The study, led by Callum Kingwell (Smithsonian Tropical Research Institute and Princeton University) and Bill Wcislo (STRI), is the first to identify a queen pheromone in a flexible social insect. Methylalkanes require a dietary protein also essential for reproduction, making the signal honest. The research provides insights into the evolution of social complexity in insects.