[2][3] Molecular evidence, derived from whole-genome sequencing, has revealed that the chicken was first domesticated from red junglefowl ca.

[2][4] Since then, the domestic form has spread around the world, and they are bred by humans in their millions for meat, eggs, colourful plumage and companionship.

[6] The red junglefowl was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the binomial name Phasianus gallus.

[7] Linnaeus specified the type locality as "India orientali" but this has been restricted to the island of Pulo Condor Côn Đảo off the coast of Vietnam.

The male eclipse pattern includes a black feather in the middle of the back and small red-orange plumes spread across the body.

The male's tail is composed of long, arching feathers that initially look black, but shimmer with blue, purple, and green in direct light.

She also has a very small comb and wattles (fleshy ornaments on the head that signal good health to rivals and potential mates) compared to the males.

[14] Male red junglefowl have a shorter crowing sound than domestic roosters; the call cuts off abruptly at the end.

[13] This serves both to attract potential mates and to make other male birds in the area aware of the risk of fighting a breeding competitor.

[17] The range of the wild form stretches from India, Nepal and Bangladesh in the west, and eastwards across southern China, to Indochina; south/southeast into Malaysia, Singapore, the Philippines, and Indonesia.

[21] Junglefowl use both deforested and regenerating forests,[22] and often are found near human settlements[23] or areas of regrowth from slash-and-burn cultivation.

[27] Flight in these birds is almost purely confined to reaching their roosting areas at sunset in trees or any other high and relatively safe places free from ground predators, and for escape from immediate danger through the day.

[14] Fruits and seeds of scores of plant species have been identified from junglefowl crops, along with grasses, leaves, roots, and tubers.

[14][37] In addition, red junglefowl capture a wide variety of arthropods, other invertebrates, and vertebrates such as small lizards.

[14][21] Plant materials constitute a higher proportion of the diet of adult red junglefowl than do arthropods and other animals.

[2] Domestication occurred about 8,000 years ago, as based on molecular evidence[2] from a common ancestor flock in the bird's natural range, and then proceeded in waves both east and west.

[38][39] Zoogeography and evolutionary biology point to the original domestication site of chickens as somewhere in Mainland Southeast Asia and southern China in the Neolithic.

[40] Other archaeological evidence suggests domestication dates around 7,400 BP from the Chishan site, in the Hebei province of China.

Wild-type red junglefowl are thought to be facing threats due to hybridisation at forest edges, where domesticated free-ranging chickens are common.