Change of Dufour gland contents with age of workers of Formica sanguinea (Hymenoptera: Formicidae)

The Dufour glands of newly emerged adult workers of F.sanguinea Latr. are almost empty, but the gland fills slowly over several months. The amount and composition of the secretion varies between individuals but the mean values change with age, the composition reaching its final value only in old foraging workers. Undecane is the major component for most of the period, but its proportion decreases with age. The amount of (Z,E)‐α‐farnesene increases with age and finally becomes the major component. The change in composition may reflect changes in worker function.