Bird of Paradise Parotia lawesii

With his striking, iridescent plumage, the male bird of paradise is considered one of the prettiest boys of the avian world. Now new research reveals the secret of his shimmering feathers.

The male Lawes's parotia, a species of bird of paradise in Papua New Guinea, attracts females with a complex dance involving bobbing, bowing and gyrating that causes his breast feathers to appear yellow-orange from the front, but blue-green when viewed at an angle.

A study by Sussex neuroscientist Professor Daniel Osorio, together with colleagues in the Netherlands and Australia, has found that this unique effect is due to the shape of the microscopic structures on the main barb of the feather. These 'barbules' have a boomerang-like shape, which creates a three-way mirror effect.

In other birds with iridescent plumage, the barbules have a more flattened. oval shape. But in the Lawes's parotia, the boomerang shape reflects colour in different directions and causes more dramatic changes.

Daniel says: "So far as we know, there are no direct tests of how birds respond to colour, but it seems the parotia's breast plumage is specifically adapted to produce hue-shifts.

"It would be interesting to find out what information these colour changes give to the female and how they interact with the male bird's mating display."

Watch the bird of paradise's dazzling dance on the BBC's Planet Earth