Indian Peafowl
Indian Peafowl | |
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Male (peacock) displaying | |
Female (peahen) | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Galliformes |
Family: | Phasianidae |
Subfamily: | Phasianinae |
Genus: | Pavo |
Species: | P. cristatus |
Binomial name | |
Pavo cristatus Linnaeus, 1758 | |
Range map |
Taxonomy and naming
The Indian Peafowl was one of the many species originally described by Linnaeus in his work, Systema Naturae, in 1758 and it still bears its original name of Pavo cristatus. The Latin genus name Pavo and the Anglo-Saxon Pawe (from which the word "Peacock" is derived) are believed to be echoic in their origin and based on the usual call of the bird. The species name cristatus refers to the crest.The earliest usage of the word in written English is from around 1300 and spelling variants include pecok, pekok, pecokk, peacocke, peocock, pyckock, poucock, pocok, pokok, pokokke, and poocok among others. The current spelling was established in the late 17th century. Chaucer (1343–1400) used the word to refer to a proud and ostentatious person in his simile "proud a pekok" in Troilus and Criseyde (Book I, line 210)
The Greek word for peacock was taos and was related to the Persian "tavus" (as in Takht-i-Tâvus for the famed Peacock Throne). The Hebrew word tuki (plural tukkiyim) has been said to have been derived from the Tamil tokei but sometimes traced to the Egyptian tekh.
Description
The most common calls are a loud pia-ow or may-awe. The frequency of calling increases before the Monsoon season and may be delivered in alarm or when disturbed by loud noises. In forests, their calls often indicate the presence of a predators such as the tiger. They also make many other calls such as a rapid series of ka-aan..ka-aan or a rapid kok-kok.
Mutations and hybrids
Cross between a male Green Peafowl, Pavo muticus and a female Indian Peafowl, P. cristatus, produces a stable hybrid called a "spalding", named after Mrs. Keith Spalding, a bird fancier in California.There can be problems if birds of unknown pedigree are released into the wild, as the viability of such hybrids and their offspring is often reduced (see Haldane's Rule and outbreeding depression).
Distribution and habitat
The Indian Peafowl is a resident breeder across the Indian subcontinent and is found in the drier lowland areas of Sri Lanka. In South Asia, it is found mainly below an altitude of 1,800 metres (1.1 mi) and in rare cases seen at about 2,000 metres (1.2 mi).It is found in moist and dry-deciduous forests, but can adapt to live in cultivated regions and around human habitations and is usually found where water is available. In many parts of northern India, they are protected by religious practices and will forage around villages and towns for scraps. Some have suggested that the peacock was introduced into Europe by Alexander the Great, while others say the bird had reached Athens by 450 BC and may have been introduced even earlier. It has since been introduced in many other parts of the world and has become feral in some areas.Behaviour and ecology
Peafowl are best known for the male's extravagant display feathers which, despite actually growing from their back, are thought of as a tail. The "train" is in reality made up of the enormously elongated upper tail coverts. The tail itself is brown and short as in the peahen. The colours result not from any green or blue pigments but from the micro-structure of the feathers and the resulting optical phenomena. The long train feathers (and tarsal spurs) of the male develop only after the second year of life. Fully developed trains are found in birds older than four years. In northern India, these begin to develop each February and are moulted at the end of August.The moult of the flight feathers may be spread out across the year.Peafowl produce loud calls especially in the breeding season. They may call at night when alarmed and neighbouring birds may call in a relay like series. Nearly seven different call variants have been identified in the peacocks apart from six alarm calls that are commonly produced by both sexes.
Peafowl roost in groups during the night on tall trees but may sometimes make use of rocks, buildings or pylons. In the Gir forest, they chose tall trees in steep river banks. Birds arrive at dusk and call frequently before taking their position on the roost trees. Due to this habit of congregating at the roost, many population studies are made at these sites. The population structure is not well understood. In a study in northern India (Jodhpur), the number of males was 170-210 for 100 females but a study involving evening counts at the roost site in southern India (Injar) suggested a ratio of 47 males for 100 females.
Sexual selection
The ornate train is believed to be the result of female sexual selection as males raise the feathers into a fan and quiver them as part of courtship display. However, several recent studies have failed to find a relation between the displayed eyespot numbers with mating success. Although the removal of eyespots makes males less successful in mating, this result is questionable because eyespot removal substantially changes the appearance of male peafowls. It is likely that females mistake these males for sub-adults or perceive that they have experienced severe physical hazards. Moreover, in a feral peafowl population, there is little variation in the number of eyespots in adult males. It is normally rare for male adults to lose a significant number of eyespots in such populations. Therefore, females’ selection might depend on other sexual traits of males’ trains. Many studies have suggested that the quality of train is an honest signal of the condition of males and that peahens select males on the basis of their plumage. A recent study on a natural population of Indian peafowls in the Shivalik area of India has proposed a “high maintenance handicap” theory. It states that only the fittest males can afford the time and energy to maintain a long tail. Therefore, the long train is an indicator of good body condition, which results in greater mating success. While train length seems to positively correlate to MHC diversity in males, females do not appear to use train length to choose males.[35] A study in Japan also suggests that peahens do not choose peacocks based on their ornamental plumage, including train length, number of eyespots and train symmetry. Another study in France brings up two possible explanations for the conflicting results that exist. The first explanation is that there might be a genetic variation of the trait of interest under different geographical areas due to a founder effect and/or a genetic drift. The second explanation suggests that “the cost of trait expression may vary with environmental conditions,” so that a trait that is indicative of a particular quality may not work in another environment.
There are two theories regarding to the evolution of male ornamental plumage, i.e. the train. One is the Fischer’s runaway model, which postulates a positive feedback relationship between female preference for elaborate train and the elaborate train itself. This model assumes that the male train is a relatively recent evolutionary adaptation. However, a molecular phylogeny study on peacock-pheasants shows the opposite; the most recently evolved species is actually the least ornamented one.This finding suggests a chase-away sexual selection, in which “females evolve resistance to male ploys”. A study in Japan goes on to conclude that “peacocks’ train is an obsolete signal for which female preference has already been lost or weakened”.
Breeding
Peacocks are polygamous, and the breeding season is spread out but appears to be dependent on the rains. Peafowls usually reach sexual maturity at the age of 2 to 3 years old. Several males may congregate at a lek site and these males are often closely related.Feeding
Peafowl are omnivorous and eat seeds, insects, fruits, small mammals and reptiles. They feed on small snakes but keep their distance from larger ones. In the Gir forest of Gujarat, a large percentage of their food is made up of the fallen berries of Zizyphus. Around cultivated areas, peafowl feed on a wide range of crops such as groundnut, tomato, paddy, chilly and even bananas. Around human habitations, they feed on a variety of food scraps and even human excreta. In the countryside, it is particularly partial to crops and garden plants.Mortality factors
Adult peafowl can usually escape ground predators by flying into trees. Large animals such as leopards, dholes and tigers can sometimes ambush them however, and in some areas such as the Gir forest, peafowl are fairly common prey for such formidable predators.Foraging in groups provides some safety as there are more eyes to look out for predators.They are also sometimes hunted by large birds of prey such as the Crested Hawk-Eagle and Rock Eagle-owl.Chicks are somewhat more prone to predation than adult birds. Adults living near human habitations are sometimes hunted by domestic dogs or by humans in some areas (southern Tamil Nadu) for folk-remedies involving the use of "peacock oil".In captivity, birds have been known to live for 23 years but it is estimated that they live for only about 15 years in the wild.
Conservation and status
Indian Peafowl are widely distributed in the wild across South Asia and protected both culturally in many areas and by law in India. Conservative estimates of the population put them at more than 100,000. Illegal poaching for meat however continues and declines have been noted in parts of India. However, outside India eating peacock is legal. In China, a very profitable industry has been developed in peacock feeding, breeding, hatching, promotion, recovery, commodity processing, export and so on. Jiangxi Zong Technology Co. Ltd., which was established in 1998, currently, has the world's largest breeding stock of peacocks (about ten thousand peacocks) and is known as the "Peacock King" in China.Poaching of peacocks for their meat and feathers and accidental poisoning by feeding on pesticide treated seeds are known threats to wild birds. Methods to identify if feathers have been plucked or have been shed naturally have been developed as Indian law allows the collection of feathers that have been shed.
In parts of India, the birds can be a nuisance to agriculture as they damage crops.Its adverse effects on crops,however, seem to be offset by the beneficial role it plays by consuming prodigious quantities of pests such as grasshoppers. They can also be a problem in gardens and homes where they damage plants, attack their reflections breaking glass and mirrors, perch and scratch cars or leave their droppings. Many cities where they have been introduced and gone feral have peafowl management programmes. These include educating citizens on how to prevent the birds from causing damage while treating the birds humanely.
In culture
These birds were often kept in menageries and as ornaments in large gardens and estates. A reference in the Bible mentions a peacock owned by King Solomon (I Kings, chapt X 22 and 23). In medieval times, knights in Europe took a "Vow of the Peacock" and decorated their helmets with its plumes. Feathers were buried with Viking warriors and the flesh of the bird was said to cure snake venom and many other maladies. Numerous uses in Ayurveda have been documented. Peafowl were said to keep an area free of snakes. In 1526, the legal issue as to whether peacocks were wild or domestic fowl was thought sufficiently important for Cardinal Wolsey to summon all the English judges to give their opinion, which was that they are domestic fowl.
In Anglo-Indian usage of the 1850s, to peacock meant making visits to ladies and gentlemen in the morning. In the 1890s, the term "peacocking" in Australia referred to the practice of buying up the best pieces of land ("picking the eyes") so as to render the surrounding lands valueless. The English word "peacock" has come to be used to describe a man who is very proud or gives a lot of attention to his clothing.
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