Editing Bee learning and communication (section)

====Color learning rates and preferences====
The German scientist Randolf Menzel continued the study of color vision in honey bees with more detailed tests. He was curious about whether bees would learn certain colors faster than others. He used lights of various color and intensity to project circles of light on a surface, a set-up like that used by von Frisch except that, by using light instead of cardboard, Menzel was able to easily change the intensity and color of the circles.<ref name="Carew2000"/> 
[[Image:Bee gathering pollen, Montreux.jpg|thumb|left|alt=bee collecting pollen.|Honey bee collecting pollen]]

To test bees ability to distinguish between two different colors, Menzel placed a small dish containing sugar-water in one circle and a second empty dish some distance away on a differently colored circle.  A single bee was placed equidistant between the two circles and allowed to choose between the dishes. The bees quickly learned to choose the color signaling the dish with the reward, and Menzel was able to measure how quickly the bees learned this task with various color differences.<ref name="Menzel">Menzel, R. and Backhaus, W. 1989. Color vision in honey bees: Phenomena and physiological mechanisms. In D. Stavenga and R. Hardie (eds): Facets of vision. Berlin-Heidelberg-New York: 281-297</ref>

Menzel's results showed that bees do not learn to discriminate between all color pairs equally well. Bees learned the fastest when violet light was rewarded, and the slowest when the light was green; the other colors fell somewhere in between. This evidence of inherent bias is evolutionarily reasonable, given that bees forage for differently-colored nectar-bearing flowers, many of which are to be found in green foliage which does not signal reward.<ref name="Carew2000"/><ref name="Menzel"/>