New York - Some flowers have found a nifty way to get the blues.
They create a blue halo, to attract the bees they need for pollination, say scientists at Cambridge University.
Bees are drawn to the colour blue, but it’s hard for flowers to make that colour in their petals. Instead, some flowers use a trick of physics.
They produce a blue halo when sunlight strikes a series of tiny ridges in their thin waxy surfaces. The ridges alter how the light bounces back, which affects the colour that one sees.
The halos appear over pigmented areas of a flower, and people can see them over darkly coloured areas if they look from certain angles. The halo trick is uncommon among flowers. But many tulip species are among those that can do it.