Ancient Fertility Pheromone

Keeping workers sterile and maintaining the fertility of queens is essential for the stability of many insect colonies. According to a study in Science, this common goal is achieved by several species of wasps, bees, and ants through use of chemically similar hydrocarbon pheromones (2014, DOI: 10.1126/science.1244899). This discovery is unexpected because these three groups of insects have a common solitary insect ancestor but evolved colony lifestyles independently, explains Tom Wenseleers, a chemical ecologist at the University of Leuven, in Belgium, who led the research. Wenseleers and colleagues propose that the solitary ancestor used the waxy, saturated hydrocarbon pheromone as a sex signal to attract mates. Later on, the sex signal evolved to facilitate colony life. It now functions to sterilize female workers. The pheromones, which are saturated carbon chains with 25 to 29 carbon atoms that sometimes include a methyl group on the third carbon, may have industrial value. For example, the signal could be used to help ensure social cohesion in colonies of bumblebees that are shipped around the world to pollinate plants in commercial greenhouses.