Eye structure correlates with distinct foraging-bout timing in primitive ants

Social insects have evolved remarkable physiological adaptations and behavioural strategies that enable them to access new temporal foraging niches (for example [1]). Here we report striking correlations between the timing of foraging bouts and the modification of eye structure in four species of ants belonging to the primitive genus Myrmecia. Most noteworthy, photoreceptor diameters progressively increase from 1.3 μm in strictly day-active species, to 5.9 μm in predominantly night-active species