Unlike many hybrids, spaldings are fertile and generally benefit from hybrid vigour spaldings with a high-green phenotype do much better in cold temperatures than the cold-intolerant green peafowl while still looking like their green parents. Hybrids between Indian peafowl and Green peafowl are called Spaldings, after the first person to successfully hybridise them, Mrs. While initially gynandromorphism was suspected, researchers have suggested that changes in mature birds are due to a lack of estrogen from old or damaged ovaries, and that male plumage and calls are the default unless hormonally suppressed. Mature peahens have been recorded as suddenly growing typically male peacock plumage and making male calls. They vary between yellow and tawny, usually with patches of darker brown or light tan and "dirty white" ivory. Females of the Indian and African species are dull grey and/or brown.Ĭhicks of both sexes in all the species are cryptically coloured. These feathers are much shorter than those of the Indian and green species, and the ocelli are much less pronounced. The Congo peacock male does not display his covert feathers, but uses his actual tail feathers during courtship displays. Unlike Indian peafowl, the green peahen is similar to the male, but has shorter upper tail coverts, a more coppery neck, and overall less iridescence. Green peafowl differ from Indian peafowl in that the male has green and gold plumage and black wings with a sheen of blue. The female also displays her plumage to ward off female competition or signal danger to her young. The Indian peahen has a mixture of dull grey, brown, and green in her plumage. Both sexes of all species have a crest atop the head. These feathers are marked with eyespots, best seen when a peacock fans his tail. The peacock train consists not of tail quill feathers, but highly elongated upper tail coverts. In both species, females are a little smaller than males in terms of weight and wingspan, but males are significantly longer due to the "tail", also known as a "train". The Indian peacock has iridescent blue and green plumage, mostly metallic blue and green, but the green peacock has green and bronze body feathers. More recently, Amotz Zahavi proposed in his handicap theory that these features acted as honest signals of the males' fitness, since less-fit males would be disadvantaged by the difficulty of surviving with such large and conspicuous structures. Charles Darwin suggested that they served to attract females, and the showy features of the males had evolved by sexual selection. The functions of the elaborate iridescent colouration and large "train" of peacocks have been the subject of extensive scientific debate. The latter is especially prominent in the Asiatic species, which have an eye-spotted "tail" or "train" of covert feathers, which they display as part of a courtship ritual. Male peafowl are known for their piercing calls and their extravagant plumage. The two Asiatic species are the blue or Indian peafowl originally of the Indian subcontinent, and the green peafowl of Southeast Asia the one African species is the Congo peafowl, native only to the Congo Basin. Male peafowl are referred to as peacocks, and female peafowl are referred to as peahens, even though peafowl of either sex are often referred to colloquially as "peacocks". Peafowl is a common name for three bird species in the genera Pavo and Afropavo within the subtribe Pavonina of the family Phasianidae, the pheasants and their allies. Cladistically included but traditionally excluded taxa