Thanks to the observations and scientific investigations of Austrian Nobel Prize-winning ethologist Karl von Frisch, we know many things about bees that are not perceptible to the human eye.
For instance, do you know that bees can see ultra-violet light? This is very useful for them, because many flowers that want to lure bees to pollinate them “advertise” their nectar by coloring the area surrounding the nectar well in ultra-violet purple color.
This mutually rewarding relationship ensures that the flower gets itself pollinated and the bee has a fine drink of nectar and probably picks up a lot of pollen to take home to the hive.
Perhaps we should ask, can bees see colors? The answer is yes, they can see many colors, including the ultra-violet light that humans can’t see, but they are unable to distinguish the color red.
This video is 2:57 minutes long and gives you a chance to "bee see" a flower:
Karl von Frisch, author of the book The Dancing Bees, performed easy-to-do experiments nearly a century ago to prove this.
He set out two identical pieces of blue paper, and only put a few drops of honey on one of them. Several times the bees were exposed to the papers, and they landed on the one with honey and consumed it. They went back to the hive and then returned for more honey. After the pattern repeated a few times von Frisch took the honey paper away.
He replaced the honey paper with identical sheets of red and blue paper. There was no honey for the bees when they returned. Still, they went to the blue paper every time. This provided evidence that bees remembered which paper had contained honey, as well as indicating they can differentiate between colors. In fact, they can distinguish between blue, ultraviolet and green, but not between black and red.
Next, Karl von Frisch performed another simple experiment because he wanted to know that the results of the first experiment were not due to bees having grey scale vision, where different shades of grey were involved. He set out a range of papers from white to black on the paper, and many grey papers in between. Then he added one blue paper. The bees that remembered the previous experiment and knew that blue = honey, went straight to the blue paper. This addressed the fact that bees are not just judging degrees of brightness or lightness, they see color. They failed the test when having to choose between grey and red paper, they were unable to see red.
The reason they can’t see red is because they see wavelengths between approximately 300-650 nanometers, and red is outside that spectrum. Scientists say the most attractive colors to bees are purple, violet and blue. But they do see ultraviolet light, and a beautiful hue called “bee’s purple” which is a blend of yellow and ultraviolet light that is invisible to humans. Bee’s purple leads them to flowers with nectar rewards.
So, let’s send Karl von Frisch some otherworldly gratitude for his studies into bee, our most beloved pollinator.