ORIENTATION CUES USED BY ANTS

The cues used for orientation during homing were examined in ants from 3 subfamilies, i.e. Atta laevigata, Acromyrmex octospinosus, Acromyrmex rugosus, Trachymyrmex urichi; Ectatomma ruidum and Pseudomyrmex termitarius, by means of a Y-maze experiment. The results showed that ants use various cues for orientation through a maze. For each ant species, the cues may be classified in a kind of species-specific hierarchy according to their importance during homing. In addition to visual and chemical orientation, empirical evidence supporting the existence of a topochemical is presented. P. termitarius uses a kinesthetic sense for orientation. Learning of the cues in the laboratory is not directly related to the respective hierarchy used for orientation through a maze by each species, but seems to be inversely correlated with the social complexity of the species. The number of cues used for orientation correlates directly with the social complexity of the species. A divergent evolutionary development of orientation strategies, even among closely related species, is proposed. © 1990 Masson.