The Physical Basis of the Beauty in Peacock Feathers Reveale
Nobody looking at the patterns in peacock feathers can avoid being amazed at their beauty. One of the latest pieces of research by scientists has revealed that there is an astonishing design at the basis of these patterns.
Chinese scientists have discovered a delicate mechanism of tiny hairs in peacock feathers filtering and reflecting different wavelengths of light. According to a study performed by Fudan University physicist Jian Zi and colleagues, published in the journal Proceedings of the National Academy of Sciences, the feathers' bright colors are produced not by pigments, but by tiny, two-dimensional crystal-like structures. (1)
Zi and his colleagues used powerful electron microscopes to reveal the basis of the colors in the feathers. They examined the barbules of the male green peacock (Pavo rnuticus), in other words the even smaller micro hairs that come off of barbs emerging from the central stem of the feather. Under the microscope, they encountered the lattice design in the black-and-white picture to the right. This consisted of rods made of melanin, a protein, bound together with keratin, another protein. The researchers observed that these two-dimensional structures, each with a width hundreds of times thinner than a human hair, were arranged one behind the other on the micro hairs. Using additional optical examinations and calculations, the scientists examined the spaces between the crystals and their effects. As a result, it was revealed that the dimensions and shapes of these spaces in the lattice led to light being reflected at slightly different angles and thus to a variation in color.
"The male peacock tail contains spectacular beauty because of the brilliant, iridescent, diversified, colorful eye patterns," said Zi, who continued, "when I watched the eye pattern against the sunshine, I was amazed by the stunning beauty of the feathers." (2) Zi stated that until their study, the exact physical mechanism producing the colors in peacock feathers had not been known, and that although the mechanisms they had revealed were simple, they were absolutely ingenious.
Obviously, there is a very specially regulated design in peacock feather patterns. The tiny lattices and spaces between them are of the greatest importance in this design. The adjustment between the spaces is particularly striking. Were these not so arranged as to reflect light at slightly different angles to one another, then this variation in color would not take place.
The greater part of the color in the peacock feather...