Bees and wasps are known to be trichromats (three classes of photoreceptors). Ants were thought to be the only hymenopterans to be dichromats, being sensitive to UV and green wavelength of the spectrum. Several behavioural experiments have suggested that ants do use colour vision, but it has been unclear whether ants are dichromats, trichromats or tetrachromats. Teaming up with electrophysiology experts Yuri Ogawa, Jan Hemmi, Marcin Falkowski at UWA and visual ecologist Jochen Zeil at ANU we show from intracellular and extracellular recordings that ant photoreceptors have three spectral sensitivities, sensitive to UV, blue and green wavelength – that allows for trichromacy. Interestingly, this holds good for ants active during both day and night. We argue that colour vision may have evolved in the context of landmark guidance, since the evolution of trichromacy in insects predates the evolution of flowers.
See: Ogawa Y, Falkowski M, Narendra A, Zeil J, Hemmi JM. 2015. Three spectrally distinct photoreceptors in diurnal and nocturnal Australian ants. Proceedings of the Royal Society B 282: 20150673.