Figure 1.
Testing of honeybee colour vision.
(a) Schematic diagram of Y-maze apparatus used to test free flying bees. LED array position was varied between experimental trials (see Methods). (b) Example of an absolute irradiance spectra measurement for LED stimulus arrays. Inset shows spectral sensitivity for long- (grey circle), medium- (open circle), and short- (black circle) wavelength sensitive photoreceptors in honeybees. Colour bar indicates approximate perceived colour range in humans. Adapted from Dyer et al., 2011 using the data for honeybees from Peitsch et al. 1992. (c) Plots of LED stimuli in a Maxwell triangle colour model representing the trichromatic (ultraviolet, UV; blue, B; green, G) colour vision of honeybees. Spectral loci show theoretical stimulation by spectrally pure radiation.
Table 1.
Colour distance in a Maxwell colour triangle for ‘colour’ stimuli that are only learnt by free flying honeybees that experience differential conditioning.
Table 2.
Chromaticity coordinates (uv, b, g) which are the normalised photoreceptor quantum catches [P(UV, Blue, Green)] for a given stimulus such that uv+b+g = 1.0.
Figure 2.
Colour learning in honeybees with differential conditioning.
(a) Acquisition curves for LED colour discrimination over 50 trials. Mean ± SEM of correct choice frequency for each 5-trial block. (b). Unrewarded touch test performance following 50 trial training interval for neutral (W: water) and aversive (Q: quinine) distractor stimuli. Mean ± SD correct touch frequency. Note that the Y-axis in each panel is abbreviated to enhance visibility. Red dotted lines indicate expected chance performance level (50%) bee choices following differential conditioning were significantly different from chance (see text for stats). In the touch tests the mean number of choices made by bees was 29.4±1.4 SEM.