Figure 5 in A behavioral analysis of achromatic cue perception by the ant Cataglyphis aenescens (Hymenoptera; Formicidae)

Figure 5. Choice frequencies of foragers in intensity discrimination experiments. Test wavelengths and intensities are given under the abscissa. The gray bars represent the choice frequencies for the rewarded intensities and the black bars represent the choice frequencies for the nonrewarded intensities. I = 1.1 × 1011 photons for 370 and 540 nm and I = 1.1 × 1012 photons for 440 and 640 nm. a) Test wavelength 370 nm, N = 44, the rewarded intensity was brighter by a factor of 40, binomial test, P> 0.05, n.s. b) Test wavelength 540 nm, N = 50, the rewarded intensity was brighter by a factor of 40, binomial test, P> 0.05, n.s. c) Test wavelength 440 nm; N = 30, the rewarded intensity was brighter by a factor of 10, binomial test, P <0.05. d) Test wavelength 640 nm; N = 30, the rewarded intensity was brighter by a factor of 10, binomial test, P <0.0001.