Figure 1.

Graphical illustration of the experimental design used for testing trail-following of Western carpenter ants, Camponotus modoc, black garden ants, Lasius niger, and European fire ants, Myrmica rubra, in response to their own trail pheromone or a complex blend of six trail pheromones (see Table 1). To account for body size differentials of large ants (Ca. modoc) and small ants (La. niger; M. rubra), bioassay arenas were large (64 cm wide × 44 cm long × 10 cm high) or small (circular, 15 cm diam × 1 cm high), and the diameter of the filter paper was 18.5 and 9 cm, respectively. Pheromone trails were applied to the filter paper along the red dotted line (which was absent in bioassays).