(Z)-11-octadecenyl acetate, an aggregation pheromone inDrosophila simulans

Existence of a male-produced pheromone, which attracts both males and females in a wind-tunnel olfactometer, has been demonstrated inDrosophila simulans (Sturtevant). A pheromone component was identified as (Z)-11-octadecenyl acetate (Z11-18: Ac), also known ascis-vaccenyl acetate. The pheromone is synergized by food volatiles. In bioassay ca. 1/1000 of a mature male equivalent of Z11-18: Ac is attractive and activity increases with increased amounts of Z11-18: Ac. Flies do not begin responding to Z11-18: Ac until after they have been away from food for at least 2 hr. Z11-18: Ac is transferred from the male to the female during mating, and the female emits the majority of the transferred Z11-18: Ac within 6 hr after mating.