Shiny bird breast
The males of a certain bird of paradise species have unique breast feathers that can reflect light in all directions at once, giving the male's breast a disco mirror ball effect.
Birds of paradise occur naturally in New Guinea and north-eastern Australia. The males of most species of these birds are splendidly decorated, with brightly coloured feathers, veils and fans. Male Parotia lawesii have beautifully coloured breast feathers, which have now been studied using a very strong microscope. The form of the feathers is unique. There are two surfaces that reflect blue light in two directions. Inside the feather is a third mirror that reflects yellow light between the blue layers. According to the researchers, there is no synthetic material known to achieve the same effect. The remarkable colours are not the result of pigments; the effect is more comparable to the colours on the surface of soap bubbles or oil.
The males use their special feathers to impress females. During their mating dance, the colours change from black to blue to yellow, and they make use of rays of sunlight to become even more impressive.
The feathers that most closely resemble the special Parotia feathers are those of the domestic pigeon. Humans perceive this bird’s neck feathers as green, magenta, or simply grey, but birds might see still more colours.
It is assumed that there are other animal species – such as hummingbirds, certain butterflies and some fish – that can create a similar effect with their feathers or scales, but these have not yet been studied in such detail.
The results of the Parotia feather research was published in the scientific journal Proceedings of the Royal Society B.