Peafowl are two Asiatic and one African species of flying bird in the genus Pavo of the pheasant family, Phasianidae, best known for the male's extravagant eye-spotted tail covert feathers, which it displays as part of courtship. The male is called a peacock, the female a peahen, and the offspring pea chicks.The adult female peafowl is grey and/or brown. Peachicks can be between yellow and a tawny colour with darker brown patches or light tan and ivory, also referred to as "dirty white". The term also embraces the Congo Peafowl, which is placed in a separate genus Afropavo.
Plumage
The male (peacock) Indian Peafowl has iridescent blue-green or green colored plumage. The peacock tail ("train") is not the tail quill feathers but the highly elongated upper tail covert feathers. The "eyes" are best seen when the peacock fans its tail. Like a cupped hand behind the ear, the erect tail-fan of the male helps direct sound to the ears.[citation needed] Both species have a crest atop the head. The female (peahen) Indian Peafowl has a mixture of dull green, brown, and grey in her plumage. Although she lacks the long upper tail coverts of the male, she has a crest. The female also displays her plumage to ward off female competition or signal danger to her young.
Coloration
As with many birds, vibrant iridescent plumage colours are not primarily pigments, but structural colouration. Optical interference Bragg reflections, based on regular, periodic nanostructures of the barbules (fiber-like components) of the feathers produce the peacock's colors. Slight changes to the spacing result in different colours. Brown feathers are a mixture of red and blue: one colour is created by the periodic structure, and the other is a created by a Fabry–Pérot interference peak from reflections from the outer and inner boundaries. Such structural colouration causes the iridescence of the peacock's hues since, unlike pigments, interference effects depend on light angle.
