The researchers found that the glossy sheen of feathers is due to the way the tiny barbules on the feathers are arranged. These barbules are covered in microscopic ridges that act like a diffraction grating, which scatters light in all directions. This scattering of light creates the appearance of shine.
The researchers were able to recreate this effect in the lab using a 3D printer to create a surface with a similar structure to the barbules on a feather. This surface was then coated with a layer of gold, which gave it a glossy sheen.
The researchers believe that this new understanding of how feathers get their shine could lead to the development of new materials that have a similar glossy appearance. These materials could be used in a variety of applications, from cosmetics to car paint.
In addition to the potential for new materials, the researchers' findings could also help us to better understand how birds use their feathers to communicate and attract mates. For example, the researchers found that the gloss of feathers is affected by the angle at which they are viewed. This means that birds can control the amount of gloss their feathers reflect by changing the way they hold their bodies.
The researchers' findings were published in the journal Nature Communications.
