Weaver ants: social establishment and maintenance of territory.

Workers of the African weaver ant Oecophylla longinoda recruit nestmates to previously unoccupied space by means of odor trails laid from the rectal gland, a hitherto unrecognized musculated organ located at the rear of the rectal sac. When enemy ants and other intruders are encountered on the territory, the Oecophylla assemble nestmates into small resting clusters by dispensing an attractant-arrestant pheromone from the sternal gland, a second newly discovered organ located on the last abdominal sternite. Under prolonged stress, additional forces are recruited to the combat area with the aid of the rectal-gland trail substance.