Researchers have unravelled the neuro-molecular mechanism of defence by honey bees when exposed to the sting alarm pheromone that they release in the face of a threat.
The team of researchers led by Prof. Martin Giurfa from the Universite de Toulouse in Toulouse, France has found that smelling isoamyl acetate, the main component in the alarm pheromone, increases the level of serotonin and dopamine in their brains, which, in turn, increases the stinging behaviour in bees and thus repels a threat. By itself, the alarm pheromone does not behave as a stimulus, but increases the likelihood of bees guarding the hive to repel a threat by stinging.
Bees collected from four hives that were involved in defending the colony were used in the study. When exposed to isoamyl acetate in the lab, guard bees collected from two colonies exhibited greater proclivity to sting than bees from the other two colonies.