When a bee flies into your garden, it doesn’t see what you and I see. Flowers leap out from much darker-looking leafy backgrounds, and they have ultraviolet-reflecting landing strips that show the way to the nectar. Some spiders might even have evolved to exploit these displays, spinning UV patterns into their webs that could work to fool a bee into thinking that it was making a beeline for a tasty treat.
If the bee manages to resist the spider’s trap, she finds her way back home by checking the pattern of polarised light in the sky. All this is seen through the pixellated window of mosaic vision, with each unit of the insect’s compound eye providing one of the 5000 dots that make up an image.
It’s a world of vision that it is difficult to imagine, but we might get some clues from people with aphakia: a condition in which the lens of the eye – which normally absorbs UV light before it can reach the retina – has been removed in surgery or lost in an accident. Bill Stark, an insect-vision researcher at Saint Louis University in Missouri, lost the lens in his left eye after an accident when he was 10 years old. He says he can see UV light as a kind of “whitish blue”, which he would see washing the scenery at a funfair, for example. Because the sight in his left eye is not great, however, he cannot see the subtle patterns in flowers that bees do.
Here. H/T Tyler Cowen