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Peafowl is a common name for two bird species of the genus Pavo and one species of the closely related genus Afropavo within the tribe Pavonini of the family Phasianidae (the pheasants and their allies). Male peafowl are referred to as peacocks, and female peafowl are referred to as peahens.
The two Asiatic species are the blue or Indian peafowl originally from the Indian subcontinent, and the green peafowl from Southeast Asia. The third peafowl species, the Congo peafowl, is native only to the Congo Basin. Male peafowl are known for their piercing calls and their extravagant plumage. 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.
The functions of the elaborate iridescent coloration and large "train" of peacocks have been the subject of extensive scientific debate. Charles Darwin suggested that they served to attract females, and the showy features of the males had evolved by sexual selection. More recently, Amotz Zahavi proposed in his handicap principle 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.
Male ( Pavo muticus) have green and bronze or gold plumage, and black wings with a sheen of blue. 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. Both males and females have spurs.
The Congo peafowl ( Afropavo congensis) male does not display his covert feathers, but uses his actual tail feathers during courtship displays. These feathers are much shorter than those of the Indian and green species, and the ocelli are much less pronounced. Females of the Indian and African species are dull grey and/or brown.
Chicks of both sexes in all the species are cryptically colored. They vary between yellow and tawny, usually with patches of darker brown or light tan and "dirty white" ivory.
Mature peahens have been recorded as suddenly growing typically male peacock plumage and making male calls. Research has 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.
Runaway selection is another hypothesis. In runaway sexual selection, linked genes in males and females code for sexually dimorphic traits in males, and preference for those traits in females.Caldwell, Roy, and Jennifer Collins. " When Sexual Selection Runs Away ." Evolution 101: Runaway Selection. N.p., n.d. 24 November 2014. The close spatial association of alleles for loci involved in the train in males, and for preference for more exuberant trains in females, on the chromosome (linkage disequilibrium) causes a positive feedback loop that exaggerates both the male traits and the female preferences.
Another hypothesis is sensory bias, in which females have a preference for a trait in a non-mating context that becomes transferred to mating, such as Merle Jacobs' food-courtship hypothesis, which suggests that peahens are attracted to peacocks for the resemblance of their eye spots to blue berries.
Multiple causalities for the evolution of female choice are also possible.
The peacock's train and iridescent plumage are perhaps the best-known examples of traits believed to have arisen through sexual selection, though with some controversy. Male Peacock's Feather Fails to Impress Females: Study . The Indian News. 27 March 2008. Male peafowl erect their trains to form a shimmering fan in their display for females. Marion Petrie tested whether or not these displays signalled a male's genetic quality by studying a feral population of peafowl in Whipsnade Wildlife Park in southern England. The number of eyespots in the train predicted a male's mating success. She was able to manipulate this success by cutting the eyespots off some of the males' tails: females lost interest in pruned males and became attracted to untrimmed ones. Males with fewer eyespots, thus having lower mating success, suffered from greater predation. She allowed females to mate with males with differing numbers of eyespots, and reared the offspring in a communal incubator to control for differences in maternal care. Chicks fathered by more ornamented males weighed more than those fathered by less ornamented males, an attribute generally associated with better survival rate in birds. These chicks were released into the park and recaptured one year later. Those with heavily ornamented feathers were better able to avoid predators and survive in natural conditions.Zuk, Marlene. (2002). Sexual Selections: What we can and can't learn about sex from animals. University of California Press; Berkeley, CA. Thus, Petrie's work shows correlations between tail ornamentation, mating success, and increased survival ability in both the ornamented males and their offspring.
Furthermore, peafowl and their sexual characteristics have been used in the discussion of the causes for sexual traits. Amotz Zahavi used the excessive tail plumes of male peafowls as evidence for his "handicap principle". Since these trains are likely to be deleterious to an individual's survival (as their brilliance makes them more visible to and their length hinders escape from danger), Zahavi argued that only the fittest males could survive the handicap of a large train. Thus, a brilliant train serves as an honest indicator for females that these highly ornamented males are good at surviving for other reasons, so are preferable mates. This theory may be contrasted with Ronald Fisher's hypothesis that male sexual traits are the result of initially arbitrary aesthetic selection by females.
In contrast to Petrie's findings, a seven-year Japanese study of free-ranging peafowl concluded that female peafowl do not select mates solely on the basis of their trains. Mariko Takahashi found no evidence that peahens preferred peacocks with more elaborate trains (such as with more eyespots), a more symmetrical arrangement, or a greater length. Takahashi determined that the peacock's train was not the universal target of female mate choice, showed little variance across male populations, and did not correlate with male physiological condition. Adeline Loyau and her colleagues responded that alternative and possibly central explanations for these results had been overlooked. They concluded that female choice might indeed vary in different ecological conditions.
In courtship, vocalisation stands to be a primary way for peacocks to attract peahens. Some studies suggest that the intricacy of the "song" produced by displaying peacocks proved to be impressive to peafowl. Singing in peacocks usually occurs just before, just after, or sometimes during copulation.
Domesticated peafowl may also eat bread and cracked grain such as oats and corn, cheese, cooked rice and sometimes cat food. It has been noticed by keepers that peafowl enjoy protein-rich food including larvae that infest granaries, different kinds of meat and fruit, as well as vegetables including dark leafy greens, broccoli, carrots, beans, beets, and peas.
Chandragupta Maurya, the founder of the Mauryan Empire, was born an orphan and raised by a family farming peacocks. According to the Buddhism tradition, the ancestors of the Maurya kings had settled in a region where peacocks ( mora in Pali language) were abundant. Therefore, they came to be known as "Moriyas", literally, "belonging to the place of peacocks". According to another Buddhist account, these ancestors built a city called Moriya-nagara ("Moriya-city"), which was so called, because it was built with the "bricks coloured like peacocks' necks". After conquering the Nanda Empire and defeating the Seleucid Empire, the Chandragupta dynasty reigned uncontested during its time. Its royal emblem remained the peacock until Emperor Ashoka changed it to a Asiatic lion, as seen in the Lion Capital of Ashoka, as well in his edicts. The peacock continued to represent elegance and royalty in India during medieval times; for instance, the Mughal emperors seat of power was called the Peacock Throne.
The peacock is represented in both the Burmese and Sinhalese people zodiacs. To the Sinhalese people, the peacock is the third animal of the zodiac of Sri Lanka.
Peacocks (often a symbol of pride and vanity) were believed to deliberately consume poisonous substances in order to become immune to them, as well as to make the colours of their resplendent plumage all the more vibrant – seeing as so many poisonous flora and fauna are so colourful due to aposematism, this idea appears to have merit. The Buddhist deity Mahamayuri is depicted seated on a peacock. Peacocks are seen supporting the throne of Amitabha, the ruby red sunset coloured archetypal Buddha of Infinite Light.
India adopted the peacock as its national bird in 1963 and it is one of the national symbols of India.
In Yazidism, the peacock is believed to represent the diversity of the world, and the colourfulness of the peacock's feathers is considered to represent of all the colours of nature. The feathers of the peacock also symbolize sun rays, from which come light, luminosity and brightness. The peacock opening the feathers of its tail in a circular shape symbolizes the sunrise.
Consequently, due to its holiness, Yazidis are not allowed to hunt and eat the peacock, ill-treat it or utter bad words about it. Images of the peacock are also found drawn around the sanctuary of Lalish and on other Yazidi shrines and holy sites, homes, as well as religious, social, cultural and academic centres.
One myth states that Hera's servant, the hundred-eyed Argus Panoptes, was instructed to guard the woman-turned-cow, Io. Hera had transformed Io into a cow after learning of Zeus's interest in her. Zeus had the messenger of the gods, Hermes, kill Argus through eternal sleep and free Io. According to Ovid, to commemorate her faithful watchman, Hera had the hundred eyes of Argus preserved forever, in the peacock's tail.Ovid I, 625. The peacock is an Eastern bird, unknown to Greeks before the time of Alexander.
The symbolic association of peacock feathers with the wings of angels led to the
belief that the waving of such liturgical fans resulted in an automated emission of
prayers. This affinity between peacocks' and angels' feathers was also expressed in
other artistic media, including paintings of angels with peacock feather wings
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Peacocks are a popular ornamental animal due to their beauty.
In addition to the wild-type "blue" colouration, several hundred variations in colour and pattern are recognised as separate morphs of the Indian Blue among peafowl breeders. Pattern variations include solid-wing/black shoulder (the black and brown stripes on the wing are instead one solid colour), pied, white-eye (the ocelli in a male's eye feathers have white spots instead of black), and silver pied (a mostly white bird with small patches of colour). Colour variations include white, purple, Buford bronze, opal, midnight, charcoal, jade, and taupe, as well as the sex-linked colours purple, cameo, peach, and Sonja's Violeta. Additional colour and pattern variations are first approved by the United Peafowl Association to become officially recognised as a morph among breeders. Alternately-coloured peafowl are born differently coloured than wild-type peafowl, and though each colour is recognisable at hatch, their peachick plumage does not necessarily match their adult plumage.
Occasionally, peafowl appear with white plumage. Although albinism peafowl do exist, this is quite rare, and almost all white peafowl are not albinos; they have a genetic condition called leucism, which causes pigment cells to fail to migrate from the neural crest during development. Leucistic peafowl can produce pigment but not deposit the pigment to their feathers, resulting in a blue-grey eye colour and the complete lack of colouration in their plumage. Pied peafowl are affected by partial leucism, where only some pigment cells fail to migrate, resulting in birds that have colour but also have patches absent of all colour; they, too, have blue-grey eyes. By contrast, true albino peafowl would have a complete lack of melanin, resulting in irises that look red or pink. Leucistic peachicks are born yellow and become fully white as they mature.
The black-shouldered or Japanning mutation was initially considered as a subspecies of the Indian peafowl ( P. c. nigripennis) (or even a separate species ( P. nigripennis)) and was a topic of some interest during Darwin's time. Others had doubts about its taxonomic status, but the English naturalist and biologist Charles Darwin (1809–1882) presented firm evidence for it being a variety under domestication, which treatment is now well established and accepted. It being a colour variation rather than a wild species was important for Darwin to prove, as otherwise it could undermine his theory of slow modification by natural selection in the wild.van Grouw, H. & Dekkers, W. 2023. The taxonomic history of Black-shouldered Peafowl; with Darwin’s help downgraded from species to variation. Bulletin of the British Ornithologists' Club
/ref> It is, however, only a case of genetic variation within the population. In this mutation, the adult male is melanistic with black wings.
During the Middle Ages period, various types of fowl were consumed as food, with the poorer populations (such as Serfdom) consuming more common , such as chicken. However, the more wealthy gentry were privileged to eat less usual foods, such as swan, and even peafowl were consumed. On a king's table, a peacock would be for ostentatious display as much as for Cuisine consumption.
From the 1864 The English and Australian Cookery Book, regarding occasions and preparation of the bird:
Instead of plucking this bird, take off the skin with the greatest care, so that the feathers do not get detached or broken. Stuff it with what you like, as truffles, mushrooms, livers of fowls, bacon, salt, spice, thyme, crumbs of bread, and a bay-leaf. Wrap the claws and head in several folds of cloth, and envelope the body in buttered paper. The head and claws, which project at the two ends, must be basted with water during the cooking, to preserve them, and especially the tuft. Before taking it off the spit, brown the bird by removing the paper. Garnish with lemon and flowers. If to come on the table cold, place the bird in a wooden trencher, in the middle of which is fixed a wooden skewer, which should penetrate the body of the bird, to keep it upright. Arrange the claws and feathers in a natural manner, and the tail like a fan, supported with wire. No ordinary cook can place a peacock on the table properly. This ceremony was reserved, in the times of chivalry, for the lady most distinguished for her beauty. She carried it, amidst inspiring music, and placed it, at the commencement of the banquet, before the master of the house. At a nuptial feast, the peacock was served by the maid of honour, and placed before the bride for her to consume.
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