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Peahen
Peafowl is a common name for three bird species in the genera '' Pavo'' and ''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, although peafowl of either sex are often referred to colloquially as "peacocks." 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 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 colouration and large "train" of peacocks have been the subject of extensive scientific debate. Charles Darwin suggested that they served ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peacock By Nihal Jabin
Peafowl is a common name for three bird species in the genera '' Pavo'' and ''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, although peafowl of either sex are often referred to colloquially as "peacocks." 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 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 colouration and large "train" of peacocks have been the subject of extensive scientific debate. Charles Darwin suggested that they ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Peafowl
The Indian peafowl (''Pavo cristatus''), also known as the common peafowl, and blue peafowl, is a peafowl species native to the Indian subcontinent. It has been introduced to many other countries. 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". Indian peafowl display a marked form of sexual dimorphism. The peacock is brightly coloured, with a predominantly blue fan-like crest of spatula-tipped wire-like feathers and is best known for the long train made up of elongated upper-tail covert feathers which bear colourful eyespots. These stiff feathers are raised into a fan and quivered in a display during courtship. Despite the length and size of these covert feathers, peacocks are still capable of flight. Peahens lack the train, have a white face and iridescent green lower neck, and dull brown plumage. The Indian peafowl lives mainly on the ground in open fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Selection
Sexual selection is a mode of natural selection in which members of one biological sex mate choice, choose mates of the other sex to mating, mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex (intrasexual selection). These two forms of selection mean that some individuals have greater reproductive success than others within a population, for example because they are more Animal sexual behaviour, attractive or prefer more attractive partners to produce offspring. Successful males benefit from frequent mating and monopolizing access to one or more fertile females. Females can maximise the return on the energy they invest in reproduction by selecting and mating with the best males. The concept was first articulated by Charles Darwin who wrote of a "second agency" other than natural selection, in which competition between mate candidates could lead to speciation. The theory was given a mathematical basis by Ronald F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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 the whole population. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Peafowl
The green peafowl or Indonesian peafowl (''Pavo muticus'') is a peafowl species native to the tropical forests of Southeast Asia. It has been listed as endangered on the IUCN Red List since 2009 because the global population has been declining rapidly and is severely fragmented due to loss of habitat. It is the national bird of Myanmar. Description Unlike the related Indian peafowl, the sexes of green peafowl are quite similar in appearance, especially in the wild. Both sexes have long upper tail coverts which cover the actual tail underneath. In the male, this extends up to and is decorated with eyespots, while in the female, the coverts are green and much shorter, just covering the tail. Outside the breeding season, however, the male's train is moulted and distinguishing the sexes can be difficult unless they are observed up close. The neck and breast feathers of both sexes are iridescent green and resemble scales. In the male, the scapulars, median, and greater wing cover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afropavo
The Congo peafowl (''Afropavo congensis''), also known as the African peafowl or ''mbulu'' by the Bakôngo, is a species of peafowl native to the Congo Basin. It is one of three peafowl species and the only member of the subfamily Pavoninae native to Africa. It is listed as Vulnerable on the IUCN Red List. History Dr. Chapin noticed that the native Congolese headdresses contained long reddish-brown feathers that he could not identify with any previously known species of bird. Later, Chapin visited the Royal Museum of Central Africa and saw two stuffed specimens with similar feathers labeled as the 'Indian peacock' which he later discovered to be the Congo peafowl, a completely different species. In 1955 Chapin managed to find seven specimens of the species. The Congo peafowl has physical characteristics of both the peafowl and the guineafowl, which may indicate that the species is a link between the two families. Description The male (pea''cock'') of this species is a larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congo Peafowl
The Congo peafowl (''Afropavo congensis''), also known as the African peafowl or ''mbulu'' by the Bakôngo, is a species of peafowl native to the Congo Basin. It is one of three peafowl species and the only member of the subfamily Pavoninae native to Africa. It is listed as Vulnerable on the IUCN Red List. History Dr. Chapin noticed that the native Congolese headdresses contained long reddish-brown feathers that he could not identify with any previously known species of bird. Later, Chapin visited the Royal Museum of Central Africa and saw two stuffed specimens with similar feathers labeled as the 'Indian peacock' which he later discovered to be the Congo peafowl, a completely different species. In 1955 Chapin managed to find seven specimens of the species. The Congo peafowl has physical characteristics of both the peafowl and the guineafowl, which may indicate that the species is a link between the two families. Description The male (pea''cock'') of this species is a large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Peafowl
The green peafowl or Indonesian peafowl (''Pavo muticus'') is a peafowl species native to the tropical forests of Southeast Asia. It has been listed as endangered on the IUCN Red List since 2009 because the global population has been declining rapidly and is severely fragmented due to loss of habitat. It is the national bird of Myanmar. Description Unlike the related Indian peafowl, the sexes of green peafowl are quite similar in appearance, especially in the wild. Both sexes have long upper tail coverts which cover the actual tail underneath. In the male, this extends up to and is decorated with eyespots, while in the female, the coverts are green and much shorter, just covering the tail. Outside the breeding season, however, the male's train is moulted and distinguishing the sexes can be difficult unless they are observed up close. The neck and breast feathers of both sexes are iridescent green and resemble scales. In the male, the scapulars, median, and greater wing cover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amotz Zahavi
Amotz Zahavi ( he, אמוץ זהבי) (August 14, 1928 – May 12, 2017) was an Israeli evolutionary biologist, a Professor in the Department of Zoology at Tel Aviv University, and one of the founders of the Society for the Protection of Nature in Israel. His main work concerned the evolution of signals, particularly those signals that are indicative of fitness, and their selection for "honesty". Biography Amotz Zahavi was influenced to study zoology by the director of the zoo at Tel Aviv, Heinrich Mendelssohn. He received his Ph.D. from Tel Aviv University in 1970. He was married to Avishag Zahavi, a biologist and a co-investigator. He died in Tel Aviv, Israel on May 12, 2017, aged 88. Scientific career Zahavi is best known for his work on the handicap principle, which explains the evolution of characteristics, behaviors or structures that appear contrary to the principles of Darwinian evolution in that they appear to reduce fitness and endanger individual organisms. Evolved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Handicap Theory
The handicap principle is a hypothesis proposed by the biologist Amotz Zahavi to explain how evolution may lead to "honest" or reliable signalling between animals which have an obvious motivation to bluff or deceive each other. It suggests that costly signals must be reliable signals, costing the signaller something that could not be afforded by an individual with less of a particular trait. For example, in sexual selection, the theory suggests that animals of greater biological fitness signal this status through handicapping behaviour, or morphology that effectively lowers this quality. The central idea is that sexually selected traits function like conspicuous consumption, signalling the ability to afford to squander a resource. Receivers then know that the signal indicates quality, because inferior-quality signallers are unable to produce such wastefully extravagant signals. History The handicap principle was proposed in 1975 by Israeli biologist Amotz Zahavi. The general ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58See the 2014 version of the ICS geologic time scale million years ago. It is the second and most recent epoch of the Neogene Period in the . The Pliocene follows the Epoch and is followed by the Epoch. Prior to the 2009 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eggs Of Peafowl At Aravath Kasaragod
Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especially chickens. Eggs of other birds, including ostriches and other ratites, are eaten regularly but much less commonly than those of chickens. People may also eat the eggs of reptiles, amphibians, and fish. Fish eggs consumed as food are known as roe or caviar. Bird and reptile eggs consist of a protective eggshell, albumen (egg white), and vitellus (egg yolk), contained within various thin membranes. Egg yolks and whole eggs store significant amounts of protein and choline, and are widely used in cookery. Due to their protein content, the United States Department of Agriculture formerly categorized eggs as ''Meats'' within the Food Guide Pyramid (now MyPlate). Despite the nutritional value of eggs, there are some potential health issues ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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