Aksoy and Camlitepe (2012) studied the behavioral responses of Formica cunicularia foragers to monochromatic spectral stimuli using the Ant Visual Discrimination Y-Maze. Each choice arm of the maze ended in a clear Perspex feeding box, from which the ants could not escape due to a fluon barrier. Lightboxes attached to the back of the feeding box delivered the spectral stimuli to the maze. The ants’ ability to discriminate between different wavelengths was tested by pairing 370 nm with 540 nm, 440 nm with 540 nm, 540 nm with 370 nm, and 640 nm with 540 nm.

The results showed that the ants could distinguish between 370 nm and 540 nm in both control and critical tests. They also discriminated between 640 nm and 540 nm in the control test but not in the critical test. However, the ants could not distinguish between 440 nm and 540 nm. The next phase of testing involved the same wavelengths at different intensities. In control tests, the intensity of the unrewarding stimulus was reduced by 2 log units. The ants could discriminate the 2-log unit intensity difference for all wavelengths except 640 nm. In critical tests, the 2-log unit difference was reduced to 1-log unit by increasing the intensity of the unrewarding stimulus. The ants failed to discriminate all wavelength pairs except 440 nm.

Additionally, the researchers tested the ants’ responses to decreasing intensities of different wavelengths on an orientation platform, which consisted of a circular plastic vessel (170 mm diameter) connected to the nest by a pipe. The ants were trained with 370, 440, 540, and 640 nm wavelengths. All wavelengths elicited a significant homeward orientation response from the foragers. In critical tests, when the intensity was reduced, the foragers continued to orient to 370 and 540 nm with 1-log and 2-log unit decreases, but they dispersed randomly below these values. The significant orientation response to 440 and 640 nm disappeared when their intensities were reduced by 1-log unit.