FIRST IDENTIFICATION OF A TRAIL PHEROMONE OF AN ARMY ANT (AENICTUS SPECIES)

Totally blind army ants carry out massive and highly organised foragin g raids, apparently guided by chemical stimuli. Until now, this phenom enon has not been closely analysed. The existence of a trail pheromone in a postpygidial gland of an Aenictus species has been demonstrated and the substances identified as methyl anthranilate and methyl nicoti nate The pheromone consists of two parts: a primer effect, caused by m ethyl nicotinate, which prepares workers to follow trails, but is not itself followed, and a releaser effect, due to methyl anthranilate, wh ich causes trail-following only in conjunction with the primer substan ce.