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121-421: The Jungle World Theme Park consists of two interconnected facilities - a family amusement park and a zoo. The Family Amusement Park provides an environment for fun family activities, including an 18-hole Mini Golf Course and thrilling rides like Time Shift Machine, Simba Tower, Giant Wheel, Dodgem Cars, Tea Cups, Hully Gully, Miami Ride, Paddle Boats and MonoTrain etc. In addition, “Mystery House” takes you through

242-520: A community, producing emotional and economic benefits. He showed that display signals among the Yomut Turkmen of northern Iran helped to secure trade agreements. These "ostentatious" displays signalled commitment to Islam to strangers and group members. Sosis demonstrated that people in religious communities are four times more likely to live longer than their secular counterparts, and that these longer lifespans were positively correlated with

363-485: 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 Japanned 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

484-468: A courtship display, the visiting female peahen will stop directly in front of the male peacock, thus providing her with the ability to assess the male at 90° to the surface of the feather. Then, the male will turn and display his feathers about 45° to the right of the sun's azimuth which allows the sunlight to accentuate the iridescence of his train. If the female chooses to interact with the male, he will then turn to face her and shiver his train so as to begin

605-496: A fact about diploid sexual reproduction noted by the mathematical biologist Ronald Fisher in the early 20th century: if there are "preference genes" correlated with choosiness in females as well as "signal genes" correlated with display traits in males, choosier females should tend to mate with showier males. Over generations, showier sons should also carry genes associated with choosier daughters, and choosier daughters should also carry genes associated with showier sons. This can cause

726-550: 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

847-420: A handicap-like signalling system was evolutionarily stable if higher quality signallers paid lower marginal survival costs for their signals. In 1982, W. D. Hamilton proposed a specific but widely applicable handicap mechanism, parasite -mediated sexual selection . He argued that in the never-ending co-evolutionary race between hosts and their parasites, sexually selected signals indicate health. This idea

968-575: A handicapping system, and a peahen knew nothing about two peacocks except the sizes of their tails, she could "infer" that the peacock with the bigger tail has greater unobservable intrinsic quality. Display costs can include extrinsic social costs, in the form of testing and punishment by rivals, as well as intrinsic production costs. Another example given in textbooks is the extinct Irish elk, Megaloceros giganteus . The male Irish elk's enormous antlers could perhaps have evolved as displays of ability to overcome handicap, though biologists point out that if

1089-454: A lack of estrogen from old or damaged ovaries, and that male plumage and calls are the default unless hormonally suppressed. As with many birds, vibrant iridescent plumage colors are not primarily pigments , but structural coloration . Optical interference Bragg reflections , based on regular, periodic nanostructures of the barbules (fiber-like components) of the feathers, produce the peacock's colors. 2D photonic-crystal structures within

1210-635: 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 peacock train consists not of tail quill feathers but highly elongated upper tail coverts. These feathers are marked with eyespots, best seen when a peacock fans his tail. All species have a crest atop the head. The Indian peahen has a mixture of dull grey, brown, and green in her plumage. The female also displays her plumage to ward off female competition or signal danger to her young. Male green peafowls ( Pavo muticus ) have green and bronze or gold plumage, and black wings with

1331-427: A logarithmic scale; for the survival cost – reproduction benefit tradeoff is assumed to mediate the evolution of sexually selected signals. Fitness depends on producing offspring, which is a multiplicative function of reproductive success given an individual is still alive times the probability of still being alive, given investment in signals. Later models have shown that the popularity of handicap principle relies on

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1452-618: 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

1573-525: A maximum of two or three antelopes per year. It was said of a particularly successful hunter: Although this hunter was sharing meat, he was not doing so in the framework of reciprocity. The general model of costly signalling is not reciprocal; rather, individuals who share acquire more mates and allies. Costly signalling applies to situations in Kalahari foraging groups where giving often goes to recipients who have little to offer in return. A young hunter

1694-399: A metaphor, and initially the handicap principle was not well received by evolutionary biologists. However, in 1984, Nur and Hasson used life history theory to show how differences in signalling costs, in the form of survival-reproduction tradeoffs, could stabilize a signalling system roughly as Zahavi imagined. Genetic models also suggested this was possible. In 1990 Alan Grafen showed that

1815-400: A mysterious and frightful exploration 10 mins walk / trip. In addition to this, children can enjoy riding on miniature horses apart from having photography with tamed Macaws and colorful Parrots. Other facilities include: The Jungle World has the biggest Zoo in the twin cities of Rawalpindi-Islamabad where wildlife species are kept in large and open air enclosures close to nature.  Some of

1936-537: A peacock serving as his mount, and the other a rooster adorning his flag. The peacock displays the divine shape of Omkara when it spreads its magnificent plumes into a full-blown circular form. In the Tantric traditions of Hinduism the goddess Tvarita is depicted with peacock feathers. A peacock feather also adorns the crest of the god Krishna . Chandragupta Maurya , the founder of the Mauryan Empire ,

2057-593: A peacock's train, loud call, and fearless behavior have been formed by natural selection (with or without sexual selection too), and served as an aposematic display to intimidate predators and rivals. This hypothesis is designed to explain Takahashi's observations that in Japan, neither reproductive success nor physical condition correlate with the train's length, symmetry or number of eyespots. Multiple hypotheses involving female choice have been posited. One hypothesis

2178-410: A self-reported survey, as the strictness of a church increased, the attendance and contributions to that church increased proportionally. In effect, people were more willing to participate in a church that has more stringent demands on its members. Despite this observation, costly donations and acts conducted in a religious context does not itself establish that membership in these clubs is actually worth

2299-792: 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. A peacock's copulation success rate depends on

2420-399: 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 peacock ( 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

2541-466: A signal and fool a receiver. Bliege Bird et al. observed turtle hunting and spear fishing patterns in a Meriam community in the Torres Strait of Australia, publishing their findings in 2001. Here, only some Meriam men were able to accumulate high caloric gains for the amount of time spent turtle hunting or spear fishing (reaching a threshold measured in kcal/h). Since a daily catch of fish

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2662-471: A symbol for joy and creativity, with quills from the bird's feathers being a metaphor for a writer's inspiration. The peacock motif was revived in the Renaissance iconography that unified Hera and Juno , and on which European painters focused. In 1956, John J. Graham created an abstraction of an 11-feathered peacock logo for American broadcaster NBC . This brightly hued peacock was adopted due to

2783-667: A symbol of immortality. In Hellenistic imagery, the Greek goddess Hera 's chariot was pulled by peacocks, birds not known to Greeks before the conquests of Alexander . Alexander's tutor, Aristotle , refers to it as "the Persian bird". When Alexander saw the birds in India, he was so amazed at their beauty that he threatened the severest penalties for any man who slew one. Claudius Aelianus writes that there were peacocks in India, larger than anywhere else. One myth states that Hera's servant,

2904-510: A territory.     Human behaviour may also provide examples of costly signals. In general, these signals provide information about a person's phenotypic quality or cooperative tendencies. Evidence for costly signalling has been found in many areas of human interaction including risk-taking, hunting, and religion. Large game hunting has been studied extensively as a signal of men's willingness to take physical risks, as well as showcase strength and coordination. Costly signalling theory

3025-421: A traditional life-history trade-off between reproduction and survival. In general, later models have shown that the key condition of honest signalling is the existence of such condition-dependent trade-off and that the cost of signals can be anything at the equilibrium for honest individuals, including zero or even negative. The reason is that deception is prevented by the potential cost of cheating and not by

3146-901: Is a common, yet less extreme, form of risk-taking. Costs associated with these donations include pain and risk of infection. If blood donation is an opportunity to send costly signals, then donors will be perceived by others as generous and physically healthy. In a survey, both donors and non-donors attributed health, generosity, and ability to operate in stressful situations to blood donors. Costly religious rituals such as genital modification , food and water deprivation , and snake handling look paradoxical in evolutionary terms. Devout religious beliefs wherein such traditions are practiced appear maladaptive. Religion may have arisen to increase and maintain intragroup cooperation. Cooperation leads to altruistic behaviour, and costly signalling could explain this. All religions may involve costly and elaborate rituals, performed publicly, to demonstrate loyalty to

3267-428: Is a highly valued characteristic in males. Torch fishing thus provides women with reliable information on the work ethic of prospective mates, which makes it an honest costly signal. In many human cases, a strong reputation built through costly signalling enhances a man's social status over the statuses of men who signal less successfully. Among northern Kalahari foraging groups, traditional hunters usually capture

3388-616: Is a poor signal of skill or strength. This suggests that energetic gains are not the primary reason men take part in turtle hunting and spear fishing. A follow-up study found that successful Meriam hunters do experience greater social benefits and reproductive success than less skilled hunters. The Hadza people of Tanzania also share food, possibly to gain in reputation. Hunters cannot be sharing meat mainly to provision their families or to gain reciprocal benefits, as teenage boys often give away their meat even though they do not yet have wives or children, so costly signalling of their qualities

3509-449: Is a ritualized method of fishing on Ifaluk whereby men use torches made from dried coconut fronds to catch large dog-toothed tuna . Preparation for torch fishing requires significant time investments and involves a great deal of organization. Due to the time and energetic costs of preparation, torch fishing results in net caloric losses for fishers. Therefore, torch fishing is a handicap that serves to signal men's productivity. Torch fishing

3630-589: Is a useful tool for understanding food sharing among hunter gatherers because it can be applied to situations in which delayed reciprocity is not a viable explanation. Instances that are particularly inconsistent with the delayed reciprocity hypothesis are those in which a hunter shares his kill indiscriminately with all members of a large group. In these situations, the individuals sharing meat have no control over whether or not their generosity will be reciprocated, and free riding becomes an attractive strategy for those receiving meat. Free riders are people who reap

3751-430: Is also the primary setting for the critically acclaimed music video for "The Great Unraveling" by internationally renowned rapper and music producer Adil Omar who chose the location based on childhood memories. This article on a zoo , aquarium , safari park , dolphinarium , or aviary is a stub . You can help Misplaced Pages by expanding it . Peafowl Peafowl is a common name for two bird species of

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3872-523: Is an honest and costly signal of phenotypic quality. Frank W. Marlowe 's The Hadza: Hunter-Gatherers of Tanzania showed that this data confirms that this is also true within the Hadza, based on the documentation on the !Kung , in Megan Biesele's book on !Kung folklore, Women Like Meat . Among the men of Ifaluk atoll, costly signalling theory can also explain why men torch fish. Torch fishing

3993-425: Is carried home by hand and turtles are frequently served at large feasts, members of the community know which men most reliably brought them turtle meat and fish. Thus, turtle hunting qualifies as a costly signal. Furthermore, turtle hunting and spear fishing are actually less productive (in kcal/h) than foraging for shellfish, where success depends only on the amount of time dedicated to searching, so shellfish foraging

4114-566: Is controversial because in non-technical usage it implies intent, to discriminate deception from honesty in human interactions. However, biologists use the phrase "honest signals" in a direct, statistical sense. Biological signals, like warning calls or resplendent tail feathers, are honest if they reliably convey useful information to the receiver. That is, the signal trait tells the receiver about an otherwise unobservable factor. Honest biological signals do not need to be perfectly informative, reducing uncertainty to zero; all they need to be useful

4235-463: Is generally the 'choosing sex' (often females) and the other the 'advertising sex' (often males). The choosing sex achieves the highest fitness by choosing the partner of the highest (genetic) quality. This quality can not be observed directly, so the advertising sex can evolve a signal, which advertises its quality. Examples of these signals include the tail of a peacock and the colouration of male sticklebacks. Such signals only work, i.e. are reliable, if

4356-511: Is generous, and has advantageous social ties. Since hunting ability is a prerequisite for marriage, men who are good hunters enter the marriage market earliest. Costly signalling theory explains seemingly wasteful foraging displays. Costly signalling can be applied to situations involving physical strain and risk of physical injury or death. Research on physical risk-taking is important because information regarding why people, especially young men, take part in high risk activities can help in

4477-433: Is guided by the same mechanism - natural selection - as any other trait in nature. The effort to discover how costs can constrain an "honest" correlation between observable signals and unobservable qualities within signallers is built on strategic models of signalling games, with many simplifying assumptions. These models are most often applied to sexually selected signalling in diploid animals, but they rarely incorporate

4598-551: Is landscaped individually to simulate the natural habitat of the species kept there. Peafowls roam freely in the main park area. Other birds include common pheasant , rose-ringed parakeet , ostrich , black swan , mute swan , silver pheasant , vulturine guineafowls , dalmatian pelican and many other types of water birds. Some mammals are Bengal tiger , lion , nilgai , hog deer , black buck , urial , Asiatic black bear , leopard , plains zebra , red kangaroo , llama , red deer and several species of monkeys. Jungle World

4719-541: Is low enough for it not to be worthwhile for crabs to test the honesty of every signal through combat. Richard Dawkins and John Krebs in 1978 considered whether individuals of the same species would act as if attempting to deceive each other. They applied a " selfish gene " view of evolution to animals' threat displays to see if it would be in their genes' interests to give dishonest signals. They criticised previous ethologists , such as Nikolaas Tinbergen and Desmond Morris , for suggesting that such displays were " for

4840-413: Is more of a long-distance attraction signal. Actions such as train rattling and wing shaking also kept the peahens' attention. Although an intricate display catches a peahen's attention, the redundant signal hypothesis also plays a crucial role in keeping this attention on the peacock's display. The redundant signal hypothesis explains that whilst each signal that a male projects is about the same quality,

4961-417: Is motivated to impress community members with daughters so that he can obtain his first wife. Older hunters may wish to attract women interested in an extramarital relationship, or to be a co-wife . In these northern Kalahari groups, the killing of a large animal indicates a man who has mastered the art of hunting and can support a family. Many women seek a man who is a good hunter, has an agreeable character,

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5082-443: Is native to India and significant in its culture. In Hinduism , the Indian peacock is the mount of the god of war , Kartikeya , and the warrior goddess Kaumari , and is also depicted around the goddess Santoshi . During a war with Asuras , Kartikeya split the demon king Surapadman in half. Out of respect for his adversary's prowess in battle, the god converted the two halves into an integral part of himself. One half became

5203-590: Is no evolutionary advantage to evolving religion over other signals of commitment such as nationality, as Irons admits. However, the reinforcement of religious rites as well as the intrinsic reward and punishment system found in religion makes it an ideal candidate for increasing intragroup cooperation. Finally, there is insufficient evidence for increase in fitness as a result of religious cooperation. However, Sosis argues for benefits from religion itself, such as increased longevity, improved health, assistance during crises, and greater psychological well-being, although both

5324-562: Is that females choose mates with good genes. Males with more exaggerated secondary sexual characteristics, such as bigger, brighter peacock trains, tend to have better genes in the peahen's eyes. These better genes directly benefit her offspring, as well as her fitness and reproductive success. 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. The close spatial association of alleles for loci involved in

5445-447: Is the likely explanation. These qualities include good eyesight, coordination, strength, knowledge, endurance, or bravery. Hadza hunters more often pair with highly fertile, hard-working wives than non-hunters. A woman benefits from mating with a man who possesses such qualities as her children will most likely inherit qualities that increase fitness and survivorship. She may also benefit from her husband's high social status. Thus, hunting

5566-458: Is the most advertised fishing occupation on Ifaluk. Women and others usually spend time observing the canoes as they sail beyond the reef. Also, local rituals help to broadcast information about which fishers are successful and enhance fishers' reputations during the torch fishing season. Several ritual behaviors and dietary constraints clearly distinguish torch fishers from other men. First, males are only permitted to torch fish if they participate on

5687-444: Is to be correct "on average", so that some behavioural response to the signal is advantageous, statistically, compared to the behaviour that would occur in absence of the signal. Ultimately the value of the signalled information depends on the extent to which it allows the receiver to increase its fitness . One type of honest signal is the signalling of quality in sexually reproducing animals. In sexually reproducing animals one sex

5808-620: The Congo Basin , is not a true peafowl. 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

5929-545: The Medieval period, various types of fowl were consumed as food, with the poorer populations (such as serfs ) consuming more common birds , 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 culinary consumption. From the 1864 The English and Australian Cookery Book , regarding occasions and preparation of

6050-659: The Mughal seat of power was called the Peacock Throne . The peacock is represented in both the Burmese and Sinhalese 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

6171-415: The advertising males' signals to selective pressure. Signals thus evolve because they modify the behaviour of the receiver to benefit the signaller. Signals may be honest, conveying information which usefully increases the fitness of the receiver, or dishonest. An individual can cheat by giving a dishonest signal, which might briefly benefit that signaller, at the risk of undermining the signalling system for

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6292-432: The handicap principle . The purpose of a sports handicapping system is to reduce disparities in performance, making the contest more competitive. In a handicap race , intrinsically faster horses are given heavier weights to carry under their saddles. Similarly, in amateur golf , better golfers have fewer strokes subtracted from their raw scores. This creates correlations between the handicap and unhandicapped performance, if

6413-490: The Christian believer drinking from the waters of eternal life. The peacock can also symbolise the cosmos if one interprets its tail with its many "eyes" as the vault of heaven dotted by the sun, moon, and stars. Due to the adoption by Augustine of the ancient idea that the peacock's flesh did not decay, the bird was again associated with immortality. In Christian iconography, two peacocks are often depicted either side of

6534-488: 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. It is, however, only a case of genetic variation within

6655-492: 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

6776-450: The Tree of Life. 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 Among Ashkenazi Jews , the golden peacock is

6897-536: 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 albino peafowl do exist, this is quite rare, and almost all white peafowl are not albinos; they have

7018-478: The addition of multiple signals enhances the reliability of that mate. This idea also suggests that the success of multiple signalling is not only due to the repetitiveness of the signal, but also of multiple receivers of the signal. In the peacock species, males congregate a communal display during breeding season and the peahens observe. Peacocks first defend their territory through intra-sexual behaviour, defending their areas from intruders. They fight for areas within

7139-402: The behaviour of receivers in ways that benefit the signaller. Traits or actions that benefit the receiver exclusively are called "cues". For example, when an alert bird deliberately gives a warning call to a stalking predator and the predator gives up the hunt, the sound is a "signal". But when a foraging bird inadvertently makes a rustling sound in the leaves that attracts predators and increases

7260-809: The benefits of group-living without contributing to its maintenance. Costly signalling theory can fill some of the gaps left by the delayed reciprocity hypothesis. Hawkes has suggested that men target large game and publicly share meat to draw social attention or to show off. Such display and the resulting favorable attention can improve a hunter's reputation by providing information about his phenotypic quality. High quality signallers are more successful in acquiring mates and allies. Thus, costly signalling theory can explain apparently wasteful and altruistic behaviour. In order to be effective, costly signals must fulfill specific criteria. Firstly, signallers must incur different levels of cost and benefit for signalling behaviour. Secondly, costs and benefits must reflect

7381-439: The best horse in a handicap race is the one carrying the largest handicap weight. According to Zahavi's theory, signallers such as male peacocks have "tails" that are genuinely handicaps, being costly to produce. The system is evolutionarily stable as the large showy tails are honest signals. Biologists have attempted to verify the handicap principle, but with inconsistent results. The mathematical biologist Ronald Fisher analysed

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7502-513: The best known example of between species deception is mimicry when individuals of one species mimic the appearance or behaviour of individuals of another species. There is a bewildering variety of mimicry types including Batesian, Müllerian, host mimicry and 'aggressive' mimicry (see main article: Mimicry ). A very frequent type is ant mimicry: myrmecomorphy (see main article: Ant mimicry ). Deception within species can be bluffing (during contest) or sexual mimicry when males or females mimic

7623-614: The bird: Signalling theory Within evolutionary biology , signalling theory is a body of theoretical work examining communication between individuals , both within species and across species. The central question is when organisms with conflicting interests, such as in sexual selection , should be expected to provide honest signals (no presumption being made of conscious intention) rather than cheating . Mathematical models describe how signalling can contribute to an evolutionarily stable strategy . Signals are given in contexts such as mate selection by females, which subjects

7744-659: The brighter and more conspicuous the organism, the more toxic it usually is. The most common and effective colours are red, yellow, black and white. The mathematical biologist John Maynard Smith discusses whether honest signalling must always be costly. He notes that it had been shown that "in some circumstances" a signal is reliable only if it is costly. He states that it had been assumed that parameters such as pay-offs and signalling costs were constant, but that this might be unrealistic. He states that with some restrictions, signals can be cost-free, reliable, and evolutionarily stable. However, if costs and benefits "vary uniformly over

7865-577: The central figures of the Yazidi religion , is symbolized with a peacock. In Yazidi creation stories , before the creation of this world, God created seven Divine Beings , of whom Tawûsî Melek was appointed as the leader. God assigned all of the world's affairs to these seven Divine Beings, also often referred to as the Seven Angels or heft sirr ("the Seven Mysteries"). In Yazidism,

7986-580: The cold-intolerant green peafowl while still looking like their green parents. Plumage varies between individual spaldings, with some looking far more like green peafowl and some looking far more like blue peafowl, though most visually carry traits of both. 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

8107-408: The colours of his eyespots (ocelli) and the angle at which they are displayed. The angle at which the ocelli are displayed during courtship is more important in a peahen's choice of males than train size or number of ocelli. Peahens pay careful attention to the different parts of a peacock's train during his display. The lower train is usually evaluated during close-up courtship, while the upper train

8228-416: The congregation to display a strong front for the peahens. Central positions are usually taken by older, dominant males, which influences mating success. Certain morphological and behavioural traits come in to play during inter and intra-sexual selection, which include train length for territory acquisition and visual and vocal displays involved in mate choice by peahens. Peafowl are forest birds that nest on

8349-627: The contribution that having two copies of each gene ( diploidy ) would make to honest signalling, demonstrating that a runaway effect could occur in sexual selection . The evolutionary equilibrium depends sensitively on the balance of costs and benefits. The same mechanisms can be expected in humans, where researchers have studied behaviours including risk-taking by young men, hunting of large game animals, and costly religious rituals, finding that these appear to qualify as costly honest signals. When animals choose mating partners, traits such as signalling are subject to evolutionary pressure. For example,

8470-402: The cost paid by the honest individuals. This potential cost of cheating (marginal cost) has to be larger than the potential (marginal) benefits for potential cheaters. In turn this implies that the honest peacock or deer need not be wasteful, it will be efficient. It is the potential cheater that needs to be less efficient. Signal selection is not a selection for waste, as claimed by Zahavi, it

8591-415: The critical misinterpretation of Grafen's model by Grafen himself. Contrary to his claims, his model is not a model of handicap signalling. Grafen's key equations show the necessity of marginal cost and differential marginal cost, nowhere in his paper was Grafen able to show the necessity of wasteful equilibrium cost (a.k.a. handicap). Grafen's model is a model of condition dependent signalling that builds on

8712-473: The development of prevention programs. Reckless driving is a lethal problem among young men in western societies. A male who takes a physical risk is sending the message that he has enough strength and skill to survive extremely dangerous activities. This signal is directed at peers and potential mates. When those peers are criminals or gang members , sociologists Diego Gambetta and James Densley find that risk-taking signals can help expedite acceptance into

8833-401: The entry costs imposed. Despite the experimental support for this hypothesis, it remains controversial. A common critique is that devoutness is easy to fake, such as simply by attending a religious service. However, the hypothesis predicts that people are more likely to join and contribute to a religious group when its rituals are costly. Another critique specifically asks: why religion? There

8954-438: The evolutionary dynamic known as Fisherian runaway , in which males become ever showier. Russell Lande explored this with a quantitative genetic model, showing that Fisherian diploid dynamics are sensitive to signalling and search costs. Other models incorporate both costly signalling and Fisherian runaway. These models show that if fitness depends on both survival and reproduction, having sexy sons and choosy daughters (in

9075-412: The expense of their immune system. The handicap principle has proven hard to test empirically, partly because of inconsistent interpretations of Zahavi's metaphor and Grafen's marginal fitness model, and partly because of conflicting empirical results: in some studies individuals with bigger signals seem to pay higher costs, in other studies they seem to be paying lower costs. A possible explanation for

9196-460: The first day of the fishing season. The community is well informed as to who participates on this day, and can easily identify the torch fishers. Second, torch fishers receive all of their meals at the canoe house and are prohibited from eating certain foods. People frequently discuss the qualities of torch fishermen. On Ifaluk, women claim that they are looking for hard-working mates. With the distinct sexual division of labor on Ifaluk, industriousness

9317-428: 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,

9438-494: 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 Congo peafowl , native only to

9559-479: The good of the species ". They argued that such communication ought to be viewed as an evolutionary arms race in which signallers evolve to become better at manipulating receivers, while receivers evolve to become more resistant to manipulation. The game theoretical model of the war of attrition similarly suggests that threat displays ought not to convey any reliable information about intentions. Deceptive signals can be used both within and between species. Perhaps

9680-490: The ground, but roost in trees. They are terrestrial feeders. All species of peafowl are believed to be polygamous . In common with other members of the Galliformes , the males possess metatarsal spurs or "thorns" on their legs used during intraspecific territorial fights with some other members of their kind. In courtship, vocalisation stands to be a primary way for peacocks to attract peahens. Some studies suggest that

9801-673: The group. In a study of risk-taking, some types of risk, such as physical or heroic risk for others' benefit, are viewed more favorably than other types of risk, such as taking drugs. Males and females valued different degrees of heroic risk for mates and same-sex friends. Males valued heroic risk-taking by male friends, but preferred less of it in female mates. Females valued heroic risk-taking in male mates and less of it in female friends. Females may be attracted to males inclined to physically defend them and their children. Males may prefer heroic risk-taking by male friends as they could be good allies. In western societies, voluntary blood donation

9922-484: The handicap is inherited, its genes ought to be selected against. The essential idea here is intuitive and probably qualifies as folk wisdom . It was articulated by Kurt Vonnegut in his 1961 short story Harrison Bergeron . In Vonnegut's futuristic dystopia , the Handicapper General uses a variety of handicapping mechanisms to reduce inequalities in performance. A spectator at a ballet comments: "it

10043-431: The handicaps work as they are supposed to, between the handicap imposed and the corresponding horse's handicapped performance. If nothing was known about two race horses or two amateur golfers except their handicaps, an observer could infer who is most likely to win: the horse with the bigger weight handicap, and the golfer with the smaller stroke handicap. By analogy, if peacock 'tails' (large tail covert feathers ) act as

10164-410: 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. The symbolism

10285-414: The inconsistent empirical results is given in a series of papers by Getty, who shows that Grafen's proof of the handicap principle is based on the critical simplifying assumption that signallers trade off costs for benefits in an additive fashion, the way humans invest money to increase income in the same currency. But the assumption that costs and benefits trade off in an additive fashion is true only on

10406-460: The increase in colour programming. NBC's first colour broadcasts showed only a still frame of the colourful peacock. The emblem made its first on-air appearance on 22 May 1956. The current, six-feathered logo debuted on 12 May 1986. Hybrids between Indian peafowl and Green peafowl are called Spaldings , after the first person to successfully hybridise them, Keith Spalding. Spaldings with a high-green phenotype do much better in cold temperatures than

10527-410: 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. Peafowl are omnivores and mostly eat plants, flower petals, seed heads, insects and other arthropods , reptiles , and amphibians . Wild peafowl look for their food scratching around in leaf litter either early in

10648-483: The layers of the barbules cause the coloration of their feathers. Slight changes to the spacing of the barbules result in different colors. Brown feathers are a mixture of red and blue: one color is created by the periodic structure and the other is created by a Fabry–Pérot interference peak from reflections from the outer and inner boundaries. Color derived from physical structure rather than pigment can vary with viewing angle, causing iridescence. Most commonly, during

10769-401: The male gray tree frog , Hyla versicolor , produces a call to attract females. Once a female chooses a mate, this selects for a specific style of male calling, thus propagating a specific signalling ability. The signal can be the call itself, the intensity of a call, its variation style, its repetition rate, and so on. Various hypotheses seek to explain why females would select for one call over

10890-573: The mating process. Charles Darwin suggested in The Descent of Man and Selection in Relation to Sex that peafowl plumage may have evolved through sexual selection : Many female progenitors of the peacock must, during a long line of descent, have appreciated this superiority; for they have unconsciously, by the continued preference for the most beautiful males, rendered the peacock the most splendid of living birds. It has been suggested that

11011-477: 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 . Tawûsî Melek (lit. 'Peacock Angel') one of

11132-741: The morning or at dusk. They retreat to the shade and security of the woods for the hottest portion of the day. These birds are not picky and will eat almost anything they can fit in their beak and digest. They actively hunt insects like ants, crickets and termites; millipedes; and other arthropods and small mammals. Indian peafowl also eat small snakes. 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. The peafowl

11253-413: The number of costly requirements demanded from religious community members. However, confounding variables may not have been excluded. Wood found that religion offers a subjective feeling of well-being within a community, where costly signalling protects against free riders and helps to build self-control among committed members. Iannaccone studied the effects of costly signals on religious communities. In

11374-557: 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. Thus, Petrie's work shows correlations between tail ornamentation, mating success, and increased survival ability in both

11495-475: 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 predators and their length hinders escape from danger), Zahavi argued that only

11616-575: The other. The sensory exploitation hypothesis proposes that pre-existing preferences in female receivers can drive the evolution of signal innovation in male senders, in a similar way to the hidden preference hypothesis which proposes that successful calls are better able to match some 'hidden preference' in the female. Signallers have sometimes evolved multiple sexual ornaments , and receivers have sometimes evolved multiple trait preferences. In biology, signals are traits, including structures and behaviours, that have evolved specifically because they change

11737-501: The patterns and behaviour of the opposite sex. A famous example is the bluegill sunfish where mimic males look like and behave like females to sneak into the guarded nests of territorial males in order to fertilize some of the eggs. In 1975, Amotz Zahavi proposed a verbal model for how signal costs could constrain cheating and stabilize an "honest" correlation between observed signals and unobservable qualities, based on an analogy to sports handicapping systems. He called this idea

11858-440: 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

11979-502: 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. In The Baptism of Hibil Ziwa , the Mandaean uthra and emanation Yushamin is described as a peacock. Ancient Greeks believed that the flesh of peafowl did not decay after death, so it became

12100-426: The population. In this mutation, the adult male is melanistic with black wings. In ancient Rome, peafowl were served as a delicacy. The dish was introduced there in approximately 35 B.C. The poet Horace ridiculed the eating of peafowl, saying they tasted like chicken. Peafowl eggs were also valued. Gaius Petronius in his Satyricon also mocked the ostentation and snobbery of eating peafowl and their eggs. During

12221-474: The predator gives up, the signaller can get back to other tasks such as feeding. Once the stalking predator is detected, the signalling prey and receiving predator thus have a mutual interest in terminating the hunt. Within species, mutual interests increase with kinship. Kinship is central to models of signalling between relatives, for instance when broods of nestling birds beg and compete for food from their parents. The term honesty in animal communication

12342-423: The prominent animals are White Tiger, Bengal Tigers, African Lions, Bears, Puma, Monkeys, Baboons, Vervet, Zebras and variety of Deers.  In addition, a variety of birds have been brought from all over the world like Pheasants, Peacocks, Parrots, Ostriches, Emus, Black Swans, Pelicans, Ducks etc. adds beauty to zoo and interest of the visitors. Wildlife species are displayed in open air enclosures. Each enclosure

12463-580: The receiver is in a possession of a resource that the signaller wants to get (resource asymmetry). Signallers can be a of different types, the type of any given signaller is assumed to be hidden (information asymmetry). Asymmetric games are frequently used to model mate choice (sexual selection) or parent-offspring interactions. Asymmetric games are also used to model interspecific interactions such as predator-prey, host-parasite or plant-pollinator signalling. Symmetric games can be used to model competition for resources, such as animals fighting for food or for

12584-514: The religious group. In this way, group members increase their allegiance to the group by signalling their investment in group interests. However, as group size increases among humans, the threat of free riders grows. Costly signalling theory accounts for this by proposing that these religious rituals are costly enough to deter free riders. Irons proposed that costly signalling theory could explain costly religious behaviour. He argued that hard-to-fake religious displays enhanced trust and solidarity in

12705-449: 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 peafowl erect their trains to form a shimmering fan in their display for females. Marion Petrie tested whether or not these displays signalled

12826-411: The risk of predation, the sound is not a signal, but a cue. Signalling systems are shaped by mutual interests between signallers and receivers. An alert bird such as a Eurasian jay warning off a stalking predator is communicating something useful to the predator: that it has been detected by the prey; it might as well quit wasting its time stalking this alerted prey, which it is unlikely to catch. When

12947-463: 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. The Indian peacock ( Pavo cristatus ) has iridescent blue and green plumage, mostly metal-like blue and green. In both species, females are

13068-540: The signal is honest. The link between the quality of the advertising sex and the signal may depend on environmental stressors, with honesty increasing in more challenging environments. Another type of honest signal is the aposematic warning signal, generally visual, given by poisonous or dangerous animals such as wasps , poison dart frogs , and pufferfish . Warning signals are honest indications of noxious prey, because conspicuousness evolves in tandem with noxiousness (a conspicuous, non-noxious organism gets eaten). Thus,

13189-454: The signallers' phenotypic quality. Thirdly, the information provided by a signal should be directed at and accessible to an audience. A receiver can be anyone who stands to benefit from information the signaller is sending, such as potential mates, allies, or competitors. Honesty is guaranteed when only individuals of high quality can pay the (high) costs of signalling. Hence, costly signals make it impossible for low-quality individuals to fake

13310-508: The signalling system to collapse. Every dishonest signal weakens the integrity of the signalling system, and so reduces the fitness of the group. An example of dishonest signalling comes from Fiddler crabs such as Austruca mjoebergi , which have been shown to bluff (no conscious intention being implied) about their fighting ability. When a claw is lost, a crab occasionally regrows a weaker claw that nevertheless intimidates crabs with smaller but stronger claws. The proportion of dishonest signals

13431-451: The stereotypical model) can be adaptive, increasing fitness just as much as having healthy sons and daughters. Perhaps the most popular tool to investigate signalling interactions is game theory . A typical model investigates an interaction between a signaller and a receiver. Games can be symmetrical or asymmetric. There can be several types of asymmetries including asymmetry in resources or asymmetry of information. In many asymmetric games

13552-624: The supposed benefits from religion and the costly-signaling mechanism have been contested. Some scholars view the emergence of language as the consequence of some kind of social transformation that, by generating unprecedented levels of public trust, liberated a genetic potential for linguistic creativity that had previously lain dormant. "Ritual/speech coevolution theory" views rituals as costly signals that ensures honesty and reliability of language communication. Scholars in this intellectual camp argue that even chimpanzees and bonobos have latent symbolic capacities that they rarely—if ever—use in

13673-473: 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

13794-416: The whole population. The question of whether the selection of signals works at the level of the individual organism or gene, or at the level of the group, has been debated by biologists such as Richard Dawkins , arguing that individuals evolve to signal and to receive signals better, including resisting manipulation. Amotz Zahavi suggested that cheating could be controlled by the handicap principle , where

13915-407: The whole range" then indeed honest signals have to be costly. Because there are both mutual and conflicting interests in most animal signalling systems, a central problem in signalling theory is dishonesty or cheating . For example, if foraging birds are safer when they give a warning call, cheats could give false alarms at random, just in case a predator is nearby. But too much cheating could cause

14036-435: 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

14157-529: Was adopted by early Christianity, thus many early Christian paintings and mosaics show the peacock. The peacock is still used in the Easter season, especially in the east. The "eyes" in the peacock's tail feathers can symbolise the all-seeing Christian God, the Church, or angelic wisdom. The emblem of a pair of peacocks drinking from a vase is used as a symbol of the eucharist and the resurrection, as it represents

14278-572: Was born an orphan and raised by a family farming peacocks. According to the Buddhist tradition , the ancestors of the Maurya kings had settled in a region where peacocks ( mora in Pali ) 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

14399-580: Was easy to see that she was the strongest and most graceful of all dancers, for her handicap bags were as big as those worn by two hundred pound men." Zahavi interpreted this analogy to mean that higher quality peacocks with bigger tails are signalling their ability to "waste" more of some resource by trading it off for a bigger tail. This resonates with Thorstein Veblen 's idea that conspicuous consumption and extravagant status symbols can signal wealth. Zahavi's conclusions rest on his verbal interpretation of

14520-716: 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 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,

14641-670: Was tested in 1994 in barn swallows , a species where males have long tail streamers. Møller found that the males with longer tails, and their offspring, did have fewer bloodsucking mites, whereas fostered young did not. The effect was therefore genetic, confirming Hamilton's theory. Another example is Lozano's hypothesis that carotenoids have dual but mutually incompatible roles in immune function and signalling. Given that animals cannot synthesize carotenoids de novo , these must be obtained from food. The hypothesis states that animals with carotenoid-depended sexual signals are demonstrating their ability to "waste" carotenoids on sexual signals at

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