Bees use isopentyl (2-methylbutyl) acetate as an alarm pheromone. When disturbed, individual bees on guard will raised their abdomen and emit the honey bee "alarm" pheromone, fanning their wings to aid its dispersal. This alerts other bees to a danger and makes them ready to sting when required. Isopentyl acetate is a major component of this pheromone. High concentrations are deposited with the stinger and venom sac in the flesh at the sting site. This incites other workers to join in the attack and sting close to the stinger which is emitting the pheromone.