Chicken: Difference between revisions

Latest revision as of 09:14, 20 November 2025

Template:Short description Script error: No such module "about". Script error: No such module "Redirect hatnote". Script error: No such module "redirect hatnote". Template:Good article Template:Pp-move Template:Protection padlock Template:Use mdy dates Template:Subspeciesbox The chicken (Gallus gallus domesticus) is a domesticated subspecies of the red junglefowl (Gallus gallus), originally native to Southeast Asia. It was first domesticated around 8,000 years ago and is one of the most common and widespread domesticated animals in the world. Chickens are primarily kept for their meat and eggs, though they are also kept as pets.^[1]

As of 2023, the global chicken population exceeds 26.5 billion, with more than 50 billion birds produced annually for consumption. Specialized breeds such as broilers and laying hens have been developed for meat and egg production, respectively. A hen bred for laying can produce over 300 eggs per year. Chickens are social animals with complex vocalizations and behaviors, and feature in folklore, religion, and literature across many societies. Their economic importance makes them a central component of global animal husbandry.

Nomenclature

Terms for chickens include:

Biddy: a chicken, or a newly hatched chicken^[2]^[3]
Capon: a castrated or neutered male chickenTemplate:Efn
Chick: a young chicken^[4]
Chook Template:IPAc-en: a chicken (Australia/New Zealand, informal)^[5]
Cock: a fertile adult male chicken^[6]^[7]
Cockerel: a young male chicken^[8]
Hen: an adult female chicken^[9]
Pullet: a young female chicken less than a year old.^[10] In the poultry industry, a pullet is a sexually immature chicken less than 22 weeks of age.^[11]
Rooster: a fertile adult male chicken, especially in North America. Originated in the 18th century, possibly as a euphemism to avoid the sexual connotation of the word cock.^[12]^[13]^[14]
Yardbird: a chicken (southern United States, dialectal)^[15]

Chicken can mean a chick, and this was historically the meaning of the word chicken,^[16] as in William Shakespeare's play Macbeth, where Macduff laments the death of "all my pretty chickens and their dam".^[17] The usage is preserved in placenames such as the Hen and Chicken Islands.^[18] In older sources, and still often in trade and scientific contexts, chickens as a species are described as common fowl or domestic fowl.^[19]

Description

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Chickens are relatively large birds, active by day. The body is round, the legs are unfeathered in most breeds, and the wings are short.^[20] Wild junglefowl can fly, whereas domestic chickens and their flight muscles are too heavy to allow them to fly more than a short distance.^[21] Size and coloration vary widely between breeds.^[20] Newly hatched chicks of both modern and heritage varieties weigh the same, about Template:Cvt. Modern varieties however grow much faster; by day 35 a Ross 708 broiler may weigh Template:Cvt as against the Template:Cvt of a heritage chicken of the same age.^[22]

Adult chickens of both sexes have a fleshy crest on their heads called a comb or cockscomb, and hanging flaps of skin on either side under their beaks called wattles; combs and wattles are more prominent in males. Some breeds have a mutation that causes extra feathering under the face, giving the appearance of a beard.^[23]

Chickens are omnivores.^[24] In the wild, they scratch at the soil to search for seeds, insects, and animals as large as lizards, small snakes,^[25] and young mice.^[26] A chicken may live for 5–10 years, depending on the breed.^[27] The world's oldest known chicken lived for 16 years.^[28]

Chickens are gregarious, living in flocks, and incubate eggs and raise young communally. Individual chickens dominate others, establishing a pecking order; dominant individuals take priority for access to food and nest sites. The concept of dominance, involving pecking, was described in female chickens by Thorleif Schjelderup-Ebbe in 1921 as the "pecking order".^[29]^[30] Male chickens tend to leap and use their claws in conflicts.^[31] Chickens are capable of mobbing and killing a weak or inexperienced predator, such as a young fox.^[32] Chickens have been thought of primarily as providers of food, but their cognition, emotions, and sociality are comparable with other birds and mammals.^[33]

File:Rooster crowing small.ogv

Crowing (with audio)

A male's crowing is a loud and sometimes shrill call, serving as a territorial signal to other males,^[34] and in response to sudden disturbances within their surroundings. Hens cluck loudly after laying an egg and to call their chicks. Chickens give different warning calls to indicate that a predator is approaching from the air or on the ground.^[35]

Reproduction and life-cycle

To initiate courting, some roosters may dance in a circle around or near a hen (a circle dance), often lowering the wing which is closest to the hen.^[36] The dance triggers a response in the hen^[36] and when she responds to his call, the rooster may mount the hen and proceed with the mating. Mating typically involves a sequence in which the male approaches the female and performs a waltzing display. If the female is unreceptive, she runs off; otherwise, she crouches, and the male mounts, treading with both feet on her back. After copulation the male does a tail-bending display.^[37]

Sperm transfer occurs by cloacal contact between the male and female, in an action called the 'cloacal kiss'.^[38] As with all birds, reproduction is controlled by a neuroendocrine system,^[39] the Gonadotropin-Releasing Hormone-I neurons in the hypothalamus. Reproductive hormones including estrogen, progesterone, and gonadotropins (luteinizing hormone and follicle-stimulating hormone) initiate and maintain sexual maturation changes. Reproduction declines with age, thought to be due to a decline in GnRH-I-N.^[40]

File:Newly-hatched chickens.jpg

Newly hatched chicks

Hens often try to lay in nests that already contain eggs and sometimes move eggs from neighbouring nests into their own. A flock thus uses only a few preferred locations, rather than having a different nest for every bird.^[41] Under natural conditions, most birds lay only until a clutch is complete; they then incubate all the eggs. This is called "going broody". The hen sits on the nest, fluffing up or pecking defensively if disturbed. She rarely leaves the nest until the eggs have hatched.^[42]

Eggs of chickens from the high-altitude region of Tibet have special physiological adaptations that result in a higher hatching rate in low oxygen environments. When eggs are placed in a hypoxic environment, chicken embryos from these populations express much more hemoglobin than embryos from other chicken populations. This hemoglobin has a greater affinity for oxygen, binding oxygen more readily.^[43]

Fertile chicken eggs hatch at the end of the incubation period, about 21 days; the chick uses its egg tooth to break out of the shell.^[36] Hens remain on the nest for about two days after the first chick hatches; during this time the newly hatched chicks feed by absorbing the internal yolk sac.^[44] The hen guards her chicks and broods them to keep them warm. She leads them to food and water and calls them towards food. The chicks imprint on the hen and subsequently follow her continually. She continues to care for them until they are several weeks old.^[45]

Inbreeding of White Leghorn chickens tends to cause inbreeding depression expressed as reduced egg number and delayed sexual maturity.^[46] Strongly inbred Langshan chickens display obvious inbreeding depression in reproduction, particularly for traits such as age when the first egg is laid and egg number.^[47]

Origin

Phylogeny

File:Red Junglefowl.jpg

Red junglefowl, the wild ancestor of the chicken

Water or ground-dwelling fowl similar to modern partridges, in the Galliformes, the order of bird that chickens belong to, survived the Cretaceous–Paleogene extinction event that killed all tree-dwelling birds and their dinosaur relatives.^[48] Chickens are descended primarily from the red junglefowl (Gallus gallus) and are scientifically classified as the same species.^[49] Domesticated chickens freely interbreed with populations of red junglefowl.^[49] The domestic chicken has subsequently hybridised with grey junglefowl, Sri Lankan junglefowl and green junglefowl;^[50] a gene for yellow skin, for instance, was incorporated into domestic birds from the grey junglefowl (G. sonneratii).^[51] It is estimated that chickens share between 71 and 79% of their genome with red junglefowl.^[50]

Domestication

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According to one early study, a single domestication event of the red junglefowl in present-day Thailand gave rise to the modern chicken with minor transitions separating the modern breeds.^[52] The red junglefowl is well adapted to take advantage of the vast quantities of seed produced during the end of the multi-decade bamboo seeding cycle, to boost its own reproduction.^[53] In domesticating the chicken, humans took advantage of the red junglefowl's ability to reproduce prolifically when exposed to a surge in its food supply.^[54]

Exactly when and where the chicken was domesticated was controversial. Genomic studies estimated that the chicken was domesticated 8,000 years ago^[50] in Southeast Asia and spread to China and India 2,000 to 3,000 years later. Archaeological evidence appeared to support domestic chickens in Southeast Asia well before 6000 BC, China by 6000 BC and India by 2000 BC.^[50]^[55]^[56] A landmark 2020 Nature study that fully sequenced 863 chickens across the world suggests that all domestic chickens originate from a single domestication event of red junglefowl (Gallus gallus) whose present-day distribution is predominantly in southeast Asia. These domesticated chickens spread across Southeast and South Asia where they interbred with local wild species of junglefowl, forming genetically and geographically distinct groups. Analysis of the most popular commercial breed shows that the White Leghorn breed possesses a mosaic of divergent ancestries inherited from subspecies of red junglefowl.^[57]^[58]^[59]

Re-examination of bones from over 600 sites, and dating of those from 23 sites, identified the earliest probable chicken bones as from central Thailand, at Ban Non Wat, some 3,250 years ago. The paleo-anatomist Joris Peters and the bioarchaeologist Greger Larson state that this coincided with the growing of rice, and propose that wild jungle fowl were attracted to eat the rice seeds, nested nearby, and became domesticated. Skeletons of birds in the Gallus genus were used as grave goods at the site, confirming domestication.^[60]

Dispersal

Austronesia

File:Map showing prehistoric diffusion of domestic chickens (Gallus gallus) into the Pacific via the Austronesian migrations (Thomson, Lebrasseur, & Austin, 2014).png

Prehistoric introduction of domesticated chickens into Oceania from the Philippines via Neolithic Austronesian expansion (starting at c. 4000 BP), inferred from genetic markers on ancient and modern chicken DNA (Thomson et al., 2014)^[61]

A word for the domestic chicken (*manuk) is part of the reconstructed Proto-Austronesian language, indicating they were domesticated by the Austronesian peoples since ancient times. Chickens, together with dogs and pigs, were carried throughout the entire range of the prehistoric Austronesian maritime migrations to Island Southeast Asia, Micronesia, Island Melanesia, Polynesia, and Madagascar, starting from at least 3000 BC from Taiwan.^[61]^[62]^[63]^[64] These chickens may have been introduced during pre-Columbian times to South America via Polynesian seafarers, but this is disputed.^[65]

Africa

Chickens reached Egypt via the Middle East for purposes of cockfighting about 1400 BC and became widely bred in Egypt around 300 BC.^[66] Three possible routes of introduction into Africa around the early first millennium AD could have been through the Egyptian Nile Valley, the East Africa Roman-Greek or Indian trade, or from Carthage and the Berbers, across the Sahara. The earliest known remains are from Mali, Nubia, East Coast, and South Africa and date back to the middle of the first millennium AD.^[66]

Americas

The possibility that domestic chickens were in the Americas before Western contact is debated by researchers, but blue-egged chickens, found only in the Americas and Asia, suggest an Asian origin for early American chickens. A lack of data from Thailand, Russia, the Indian subcontinent, Southeast Asia and Sub-Saharan Africa makes it difficult to lay out a clear map of the spread of chickens in these areas; better description and genetic analysis of local breeds threatened by extinction may also help with research into this area.^[66] Chicken bones from the Arauco Peninsula in south-central Chile were radiocarbon dated as pre-Columbian, and DNA analysis suggested they were related to prehistoric populations in Polynesia.^[67]^[68] However, further study of the same bones cast doubt on the findings.^[69]^[70]

Eurasia

Chicken remains have been difficult to date, given the small and fragile bird bones; this may account for discrepancies in dates given by different sources. Archaeological evidence is supplemented by mentions in historical texts from the last few centuries BC, and by depictions in prehistoric artworks, such as across Central Asia.^[71] Chickens were widespread throughout southern Central Asia by the 4th century BC.^[71]

Middle Eastern chicken remains go back to a little earlier than 2000 BC in Syria.^[66] Phoenicians spread chickens along the Mediterranean coasts as far as Iberia. During the Hellenistic period (4th–2nd centuries BC), in the southern Levant, chickens began to be widely domesticated for food.^[72] The first pictures of chickens in Europe are found on Corinthian pottery of the 7th century BC.^[73]^[74]

Breeding increased under the Roman Empire and reduced in the Middle Ages.^[66] Genetic sequencing of chicken bones from archaeological sites in Europe revealed that in the High Middle Ages chickens became less aggressive and began to lay eggs earlier in the breeding season.^[75]

Diseases

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File:Pesse oujheas H9N2 tanfla.JPG

8 day old chick with avian influenza

Chickens are susceptible both to parasites such as mites, and to diseases caused by pathogens such as bacteria and viruses. The parasite Dermanyssus gallinae feeds on blood, causing irritation and reducing egg production, and acts as a vector for bacterial diseases such as salmonellosis and spirochaetosis.^[76] Viral diseases include avian influenza.^[77]

Use by humans

Farming

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Chickens are common and widespread domestic animals, with a total population of 23.7 billion Template:As of.^[78] More than 50 billion chickens are reared annually as a source of meat and eggs.^[79] In the United States alone, more than 8 billion chickens are slaughtered each year for meat,^[80] and more than 300 million chickens are reared for egg production.^[81] The vast majority of poultry is raised in factory farms. According to the Worldwatch Institute, 74% of the world's poultry meat and 68% of eggs are produced this way.^[82] An alternative to intensive poultry farming is free-range farming. Friction between these two main methods has led to long-term issues of ethical consumerism. Opponents of intensive farming argue that it harms the environment, creates human health risks and is inhumane towards sentient animals.^[83] Advocates of intensive farming say that their efficient systems save land and food resources owing to increased productivity, and that the animals are looked after in a controlled environment.^[84] Chickens farmed for meat are called broilers. Broiler breeds typically take less than six weeks to reach slaughter size,^[85] some weeks longer for free range and organic broilers.^[86]

Chickens farmed primarily for eggs are called layer hens. The UK alone consumes more than 34 million eggs per day.^[87] Hens of some breeds can produce over 300 eggs per year; the highest authenticated rate of egg laying is 371 eggs in 364 days.^[88] After 12 months of laying, the commercial hen's egg-laying ability declines to the point where the flock is commercially unviable. Hens, particularly from battery cage systems, are sometimes infirm or have lost a significant amount of their feathers, and their life expectancy has been reduced from around seven years to less than two years.^[89] In the UK and Europe, laying hens are then slaughtered and used in processed foods, or sold as 'soup hens'.^[89] In some other countries, flocks are sometimes force moulted rather than being slaughtered to re-invigorate egg-laying. This involves complete withdrawal of food (and sometimes water) for 7–14 days^[90] or sufficiently long to cause a body weight loss of 25 to 35%,^[91] or up to 28 days under experimental conditions.^[92] This stimulates the hen to lose her feathers but also re-invigorates egg-production. Some flocks may be force-moulted several times. In 2003, more than 75% of all flocks were moulted in the US.^[93] Chickens are one of the most efficient sources of foods for many different purposes.

Woman feeding chickens by hand, c.1930

Woman feeding chickens by hand, c.1930
A commercial chicken house with open sides raising broiler pullets for meat

A commercial chicken house with open sides raising broiler pullets for meat
Woman with her pet rooster, Cuba

Woman with her pet rooster, Cuba

As pets

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Keeping chickens as pets became increasingly popular in the 2000s^[94] among urban and suburban residents.^[95] Many people obtain chickens for their egg production but often name them and treat them as any other pet like cats or dogs. Chickens provide companionship and have individual personalities. While many do not cuddle much, they will eat from one's hand, jump onto one's lap, respond to and follow their handlers, as well as show affection.^[96]^[97] Chickens are social, inquisitive, intelligent^[98] birds, and many people find their behaviour entertaining.^[99] Certain breeds, such as silkies and many bantam varieties, are generally docile and are often recommended as good pets around children with disabilities.^[100]

Cockfighting

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File:COCK FIGHT.JPG

A cockfight in Tamil Nadu, India, 2011

A cockfight is a contest held in a ring called a cockpit between two cocks. Cockfighting is outlawed in many countries as involving cruelty to animals.^[101] The activity seems to have been practised in the Indus Valley civilisation from 2500 to 2100 BC.^[102] In the process of domestication, chickens were apparently kept initially for cockfighting, and only later used for food.^[103]

In science

Chickens have long been used as model organisms to study developing embryos. Large numbers of embryos can be provided commercially; fertilized eggs can easily be opened and used to observe the developing embryo. Equally important, embryologists can carry out experiments on such embryos, close the egg again and study the effects later in development. For instance, many important discoveries in limb development have been made using chicken embryos, such as the discovery of the apical ectodermal ridge and the zone of polarizing activity.^[104]

The chicken was the first bird species to have its genome sequenced.^[105] At 1.21 Gb, the chicken genome is similarly sized compared to other birds, but smaller than nearly all mammals: the human genome is 3.2 Gb.^[106] The final gene set contained 26,640 genes (including noncoding genes and pseudogenes), with a total of 19,119 protein-coding genes, a similar number to the human genome.^[107] In 2006, scientists researching the ancestry of birds switched on a chicken recessive gene, talpid2, and found that the embryo jaws initiated formation of teeth, like those found in ancient bird fossils.^[108]

In culture, folklore, and religion

Script error: No such module "anchor". Script error: No such module "Labelled list hatnote". Chickens are featured widely in folklore, religion, literature, and popular culture. The chicken is a sacred animal in many cultures and deeply embedded in belief systems and religious practices.^[109] Roosters are sometimes used for divination, a practice called alectryomancy. This involves the sacrifice of a sacred rooster, often during a ritual cockfight, used as a form of communication with the gods.^[110] In Gabriel García Márquez's Nobel-Prize-winning 1967 novel One Hundred Years of Solitude, cockfighting is outlawed in the town of Macondo after the patriarch of the Buendia family murders his cockfighting rival and is haunted by the man's ghost.^[111] The pseudo-riddle "Why did the chicken cross the road?" dates to 1847, or earlier.^[112] Chickens have been featured in art in farmyard scenes such as Adriaen van Utrecht's 1646 Turkeys and Chickens and Walter Osborne's 1885 Feeding the Chickens.^[113] The nursery rhyme "Cock a doodle doo", its chorus line imitating the cockerel's call, was published in Mother Goose's Melody in 1765.^[114] The 2000 animated adventure comedy film Chicken Run, directed by Peter Lord and Nick Park, featured anthropomorphic chickens with many chicken jokes.^[115]^[116]^[117]

Etruscan askos in the form of a rooster, 4th century B.C.

Etruscan askos in the form of a rooster, 4th century B.C.
Rooster and hen, Đông Hồ folk woodcut, Vietnam

Rooster and hen, Đông Hồ folk woodcut, Vietnam
Feeding the chickens by Walter Osborne, 1885

Feeding the chickens by Walter Osborne, 1885
Joseph Crawhall III, Spanish Cock and Snail, c. 1900

Joseph Crawhall III, Spanish Cock and Snail, c. 1900
Wooden chicken mask, Bali, late 20th century

Wooden chicken mask, Bali, late 20th century
Carved and painted wooden tribal statue of a cock fight, Yoruba, West Africa, c. 2000

Carved and painted wooden tribal statue of a cock fight, Yoruba, West Africa, c. 2000
Rooster sculpture, Bordeaux, France. The bird is a symbol of the country.[118]

Rooster sculpture, Bordeaux, France. The bird is a symbol of the country.^[118]

Notes

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References

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External links

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[Online_Etymology_Dictionary-14] Online Etymology Dictionary Template:Webarchive Entry for rooster (n.), May 2019

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[CHOF-66] The Cambridge History of Food, 2000, Cambridge University Press, Vol. 1, pp. 496–499

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[108] Scientists Find Chickens Retain Ancient Ability to Grow Teeth Template:Webarchive Ammu Kannampilly, ABC News, February 27, 2006. Retrieved October 1, 2007.

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-{{Short description|Domesticated subpecies of Red Junglefowl}}
+{{Short description|Domesticated subspecies of red junglefowl}}
 {{About||the culinary use of chickens|Chicken as food|other uses|Chicken (disambiguation)}}
 {{Redirect2|Rooster|Roosters}}
 {{Redirect|Cockerel|the Fabergé egg|Cockerel (Fabergé egg)}}
+{{Good article}}
 {{Pp-move}}
-{{Pp|small=yes}}
+{{Protection padlock|small=yes}}
-{{Good article}}
+{{Use mdy dates|date=October 2025}}
-{{Use mdy dates|date=March 2025}}
 {{Subspeciesbox
 | image             = Male and female chicken sitting together.jpg
@@ Line 20: / Line 20: @@
 | range_map_caption = Chicken distribution
 }}
-The '''chicken''' ('''''Gallus gallus domesticus''''') is a domesticated subspecies of the [[red junglefowl]] (''Gallus gallus''), originally native to [[Southeast Asia]]. It was first domesticated around 8,000 years ago and is now one of the most common and widespread [[domesticated animals]] in the world. Chickens are primarily kept for [[chicken as food|their meat]] and [[egg as food|eggs]], though they are also kept as [[pet]]s.<ref>{{Cite web |last=Joshua |date=July 27, 2020 |title=Chickens and Roosters…As Pets? |url=https://journal.iaabcfoundation.org/roosters-as-pets/ |access-date=December 5, 2024 |website=IAABC Foundation Journal}}</ref>
+The '''chicken''' ('''''Gallus gallus domesticus''''') is a domesticated subspecies of the [[red junglefowl]] (''Gallus gallus''), originally native to [[Southeast Asia]]. It was first domesticated around 8,000 years ago and is one of the most common and widespread [[domesticated animals]] in the world. Chickens are primarily kept for [[chicken as food|their meat]] and [[egg as food|eggs]], though they are also kept as [[pet]]s.<ref>{{Cite web |last=Joshua |date=July 27, 2020 |title=Chickens and Roosters...As Pets? |url=https://journal.iaabcfoundation.org/roosters-as-pets/ |access-date=December 5, 2024 |website=IAABC Foundation Journal}}</ref>
-As of 2023, the global chicken population exceeds 26.5 billion, with more than 50 billion birds produced annually for consumption. Specialized breeds such as [[broiler]]s and [[laying hen]]s have been developed for meat and egg production, respectively. A hen bred for laying can produce over 300 eggs per year. Chickens are social animals with complex vocalizations and behaviors, and [[cultural references to chickens|feature prominently]] in folklore, religion, and literature across many societies. Their economic importance makes them a central component of global [[animal husbandry]] and [[agriculture]].
+As of 2023, the global chicken population exceeds 26.5 billion, with more than 50 billion birds produced annually for consumption. Specialized breeds such as [[broiler]]s and [[laying hen]]s have been developed for meat and egg production, respectively. A hen bred for laying can produce over 300 eggs per year. Chickens are social animals with complex vocalizations and behaviors, and [[cultural references to chickens|feature in folklore, religion, and literature]] across many societies. Their economic importance makes them a central component of global [[animal husbandry]].
 == Nomenclature ==
 Terms for chickens include:
 * ''Biddy'': a chicken, or a newly hatched chicken<ref>{{cite web |url=https://www.dictionary.com/browse/biddy |title=Definition of biddy |publisher=Dictionary.com |access-date=May 7, 2021 |archive-date=May 7, 2021 |archive-url=https://web.archive.org/web/20210507151125/https://www.dictionary.com/browse/biddy |url-status=live}}</ref><ref>{{cite web |url=https://www.collinsdictionary.com/us/dictionary/english/biddy |title=Biddy definition and meaning |publisher=Collins English Dictionary|access-date=May 7, 2021 |archive-date=May 7, 2021 |archive-url=https://web.archive.org/web/20210507010137/https://www.collinsdictionary.com/us/dictionary/english/biddy |url-status=live}}</ref>
-* ''[[Capon]]'': a castrated or [[neutered]] male chicken{{efn|The surgical and chemical castration of chickens is now illegal in some parts of the world.}}
+* ''[[Capon]]'': a castrated or [[neutered]] male chicken{{efn|The surgical and chemical castration of chickens is illegal in some parts of the world.}}
 * ''[[Chick (young bird)|Chick]]'': a young chicken<ref>{{cite web |title=Chick |url=https://dictionary.cambridge.org/us/dictionary/english/chick |url-status=live |publisher=Cambridge Dictionary |archive-url=https://web.archive.org/web/20150907132725/http://dictionary.cambridge.org/us/dictionary/english/chick |archive-date=September 7, 2015 }}</ref>
 * ''Chook'' {{IPAc-en|tʃ|ʊ|k}}: a chicken (Australia/New Zealand, informal)<ref>{{cite web |title=Chook |url=https://dictionary.cambridge.org/us/dictionary/english/chook |url-status=live |access-date=March 4, 2021 |website=Cambridge Dictionary |archive-url=https://web.archive.org/web/20150907151220/http://dictionary.cambridge.org/us/dictionary/english/chook |archive-date=September 7, 2015 }}</ref>
 * ''Cock'': a fertile adult male chicken<ref>{{cite web |title=Cock |url=https://dictionary.cambridge.org/us/dictionary/english/cock |url-status=live |access-date=March 4, 2021 |publisher=Cambridge Dictionary |archive-url=https://web.archive.org/web/20150907102240/http://dictionary.cambridge.org/us/dictionary/english/cock |archive-date=September 7, 2015 }}</ref><ref>{{Cite web |title=Hen |url=https://dictionary.cambridge.org/us/dictionary/english/cock |url-status=live |access-date=March 4, 2021 |publisher=Cambridge Dictionary |archive-url=https://web.archive.org/web/20150907102240/http://dictionary.cambridge.org/us/dictionary/english/cock |archive-date=September 7, 2015 }}</ref>
 * ''Cockerel'': a young male chicken<ref>{{cite encyclopedia |url=http://dictionary.reference.com/browse/cockerel |title=Cockerel |publisher=Dictionary Reference |access-date=August 29, 2010 |archive-url=https://web.archive.org/web/20160307191527/http://dictionary.reference.com/browse/cockerel |archive-date=March 7, 2016 |url-status=live }}</ref>
 * ''Hen'': an adult female chicken<ref>{{cite web |title=Hen noun |url=https://www.merriam-webster.com/dictionary/hen |publisher=[[Merriam-Webster]] |access-date=February 2, 2024}}</ref>
 * ''Pullet'': a young female chicken less than a year old.<ref>{{cite encyclopedia |url=http://dictionary.reference.com/browse/pullet |title=Pullet |publisher=Dictionary Reference |access-date=August 29, 2010 |archive-url=https://web.archive.org/web/20101109014624/http://dictionary.reference.com/browse/pullet |archive-date=November 9, 2010 |url-status=live }}</ref> In the poultry industry, a pullet is a sexually immature chicken less than 22 weeks of age.<ref>{{Cite web |title=Overview of the Poultry Industry |url=https://dese.mo.gov/sites/default/files/aged%20-PoultrySR.pdf |url-status=live |publisher=Missouri Department of Elementary and Secondary Education |page=8 |archive-url=https://web.archive.org/web/20201023230530/https://dese.mo.gov/sites/default/files/aged%20-PoultrySR.pdf |archive-date=October 23, 2020 }}</ref>
 * ''Rooster'': a fertile adult male chicken, especially in North America. Originated in the 18th century, possibly as a euphemism to avoid the sexual connotation of the word ''cock''.<ref>{{Cite web |title=Definition of Rooster |url=https://www.merriam-webster.com/dictionary/rooster |publisher=Merriam-Webster |access-date=March 6, 2021 |archive-date=April 22, 2021 |archive-url=https://web.archive.org/web/20210422030634/https://www.merriam-webster.com/dictionary/rooster |url-status=live}}</ref><ref name="Rawson">[http://www.americanheritage.com/content/why-do-we-say-17 Hugh Rawson] {{Webarchive |url=https://web.archive.org/web/20170701144833/http://www.americanheritage.com/content/why-do-we-say-17 |date=July 1, 2017 }} "Why Do We Say...? Rooster", ''American Heritage'', August–September 2006.</ref><ref name="Online Etymology Dictionary">[https://www.etymonline.com/search?q=rooster Online Etymology Dictionary] {{Webarchive |url=https://web.archive.org/web/20201111222713/https://www.etymonline.com/search?q=rooster |date=November 11, 2020 }} Entry for ''rooster (n.)'', May 2019</ref>
 * ''Yardbird'': a chicken (southern United States, dialectal)<ref name="berhardt">{{cite book |last=Berhardt |first=Clyde E. B. |title=I Remember: Eighty Years of Black Entertainment, Big Bands |year=1986 |publisher=[[University of Pennsylvania Press]] |isbn=978-0-8122-8018-0 |oclc=12805260 |page=153}}</ref>
-''Chicken'' can mean a ''chick'', and this was historically the meaning of the word chicken,<ref>{{Cite web |date=December 2024 |title=chicken (n.) |url=https://doi.org/10.1093/OED/2784909248  |access-date=February 14, 2025 |website=Oxford English Dictionary|doi=10.1093/OED/2784909248 }}</ref> as in [[William Shakespeare]]'s play ''[[Macbeth]]'', where [[Macduff (Macbeth)|Macduff]] laments the death of "all my pretty chickens and their dam".<ref>[[William Shakespeare|Shakespeare, William]], ''[[Macbeth]]'', Act 4 Scene 3, lines 217–229.</ref> The usage is preserved in placenames such as the [[Hen and Chicken Islands]].<ref>{{Cite web |title=Chicken |url=https://www.merriam-webster.com/dictionary/chicken |url-status=live |access-date=March 4, 2021 |website=Merriam Webster Dictionary |archive-url=https://web.archive.org/web/20080821163810/http://www.merriam-webster.com/dictionary/chicken |archive-date=August 21, 2008 }}</ref> In older sources, and still often in trade and scientific contexts, chickens as a species are described as ''common fowl'' or ''domestic fowl''.<ref>{{cite book |last=Stevens |first=Lewis |title=Genetics and evolution of the domestic fowl |pages=11 and throughout |year=1991 |publisher=[[Cambridge University Press]] |isbn=978-0-521-40317-7 |url=https://books.google.com/books?id=S-DXqQ9UOmAC&dq=%22domestic+fowl%22&pg=PA11}}</ref>
+''Chicken'' can mean a ''chick'', and this was historically the meaning of the word chicken,<ref>{{Cite web |date=December 2024 |title=chicken (n.) |website=Oxford English Dictionary|doi=10.1093/OED/2784909248 }}</ref> as in [[William Shakespeare]]'s play ''[[Macbeth]]'', where [[Macduff (Macbeth)|Macduff]] laments the death of "all my pretty chickens and their dam".<ref>[[William Shakespeare|Shakespeare, William]], ''[[Macbeth]]'', Act 4 Scene 3, lines 217–229.</ref> The usage is preserved in placenames such as the [[Hen and Chicken Islands]].<ref>{{Cite web |title=Chicken |url=https://www.merriam-webster.com/dictionary/chicken |url-status=live |access-date=March 4, 2021 |website=Merriam Webster Dictionary |archive-url=https://web.archive.org/web/20080821163810/http://www.merriam-webster.com/dictionary/chicken |archive-date=August 21, 2008 }}</ref> In older sources, and still often in trade and scientific contexts, chickens as a species are described as ''common fowl'' or ''domestic fowl''.<ref>{{cite book |last=Stevens |first=Lewis |title=Genetics and evolution of the domestic fowl |pages=11 and throughout |year=1991 |publisher=[[Cambridge University Press]] |isbn=978-0-521-40317-7 |url=https://books.google.com/books?id=S-DXqQ9UOmAC&dq=%22domestic+fowl%22&pg=PA11}}</ref>
 == Description ==
@@ Line 52: / Line 50: @@
 }}
-Chickens are relatively large [[bird]]s, [[Diurnality|active by day]]. The body is round, the legs are unfeathered in most breeds, and the wings are short.<ref name="Smithsonian"/> Wild [[junglefowl]] can [[bird flight|fly]]; chickens and their [[flight muscle]]s are too heavy to allow them to fly more than a short distance.<ref>{{cite web |last1=Geggel |first1=Laura |title=Forget About the Road. Why Are Chickens So Bad at Flying? |url=https://www.livescience.com/57139-why-chickens-cannot-fly.html |website=Live Science |access-date=February 3, 2024 |date=December 8, 2016 |archive-date=April 4, 2024 |archive-url=https://web.archive.org/web/20240404115622/https://www.livescience.com/57139-why-chickens-cannot-fly.html |url-status=live }}</ref> Size and coloration vary widely between breeds.<ref name="Smithsonian">{{cite web |title=Chicken |url=https://nationalzoo.si.edu/animals/domestic-chicken |publisher=Smithsonian's National Zoo & Conservation Biology Institute |access-date=February 2, 2024 |archive-date=February 2, 2024 |archive-url=https://web.archive.org/web/20240202165324/https://nationalzoo.si.edu/animals/domestic-chicken |url-status=live }}</ref> Newly-hatched chicks of both modern and heritage varieties weigh the same, about {{cvt|37|g|oz}}. Modern varieties however grow much faster; by day 35 a Ross 708 [[broiler]] may weigh {{cvt|1.8|kg|lb}} as against the {{cvt|1.05|kg|lb}} of a heritage chicken of the same age.<ref name="Schmidt Persia 2009">{{cite journal |last1=Schmidt |first1=C.J. |last2=Persia |first2=M.E. |last3=Feierstein |first3=E. |last4=Kingham |first4=B. |last5=Saylor |first5=W.W. |title=Comparison of a modern broiler line and a heritage line unselected since the 1950s |journal=Poultry Science |volume=88 |issue=12 |date=2009 |doi=10.3382/ps.2009-00055 |doi-access=free |pages=2610–2619|pmid=19903960 }}</ref>
+Chickens are relatively large [[bird]]s, [[Diurnality|active by day]]. The body is round, the legs are unfeathered in most breeds, and the wings are short.<ref name="Smithsonian"/> Wild [[junglefowl]] can [[bird flight|fly]], whereas domestic chickens and their [[flight muscle]]s are too heavy to allow them to fly more than a short distance.<ref>{{cite web |last=Geggel |first=Laura |title=Forget About the Road. Why Are Chickens So Bad at Flying? |url=https://www.livescience.com/57139-why-chickens-cannot-fly.html |website=Live Science |access-date=February 3, 2024 |date=December 8, 2016 |archive-date=April 4, 2024 |archive-url=https://web.archive.org/web/20240404115622/https://www.livescience.com/57139-why-chickens-cannot-fly.html |url-status=live }}</ref> Size and coloration vary widely between breeds.<ref name="Smithsonian">{{cite web |title=Chicken |url=https://nationalzoo.si.edu/animals/domestic-chicken |publisher=Smithsonian's National Zoo & Conservation Biology Institute |access-date=February 2, 2024 |archive-date=February 2, 2024 |archive-url=https://web.archive.org/web/20240202165324/https://nationalzoo.si.edu/animals/domestic-chicken |url-status=live }}</ref> Newly hatched chicks of both modern and heritage varieties weigh the same, about {{cvt|37|g|oz}}. Modern varieties however grow much faster; by day 35 a Ross 708 [[broiler]] may weigh {{cvt|1.8|kg|lb}} as against the {{cvt|1.05|kg|lb}} of a heritage chicken of the same age.<ref name="Schmidt Persia 2009">{{cite journal |last1=Schmidt |first1=C.J. |last2=Persia |first2=M.E. |last3=Feierstein |first3=E. |last4=Kingham |first4=B. |last5=Saylor |first5=W.W. |title=Comparison of a modern broiler line and a heritage line unselected since the 1950s |journal=Poultry Science |volume=88 |issue=12 |date=2009 |doi=10.3382/ps.2009-00055 |doi-access=free |pages=2610–2619|pmid=19903960 }}</ref>
-Adult chickens of both sexes have a fleshy crest on their heads called a comb or cockscomb, and hanging flaps of skin on either side under their beaks called [[Wattle (anatomy)|wattles]]; combs and wattles are [[Sexual dimorphism|more prominent in males]]. Some breeds have a [[mutation]] that causes extra feathering under the face, giving the appearance of a beard.<ref name=plosg>{{cite journal |last1=Guo |first1=Ying |last2=Gu |first2=Xiaorong |last3=Sheng |first3=Zheya |last4=Wang |first4=Yanqiang |last5=Luo |first5=Chenglong |last6=Liu |first6=Ranran |last7=Qu |first7=Hao |last8=Shu |first8=Dingming |last9=Wen |first9=Jie |last10=Crooijmans |first10=Richard P. M. A. |last11=Carlborg |first11=Örjan |last12=Zhao |first12=Yiqiang |last13=Hu |first13=Xiaoxiang |last14=Li |first14=Ning |display-authors=5 |title=A Complex Structural Variation on Chromosome 27 Leads to the Ectopic Expression of HOXB8 and the Muffs and Beard Phenotype in Chickens |journal=PLOS Genetics |volume=12 |issue=6 |date=June 2, 2016 |pmid=27253709 |pmc=4890787 |doi=10.1371/journal.pgen.1006071 |doi-access=free |page=e1006071}}</ref>
+Adult chickens of both sexes have a fleshy crest on their heads called a comb or cockscomb, and hanging flaps of skin on either side under their beaks called [[Wattle (anatomy)|wattles]]; combs and wattles are [[Sexual dimorphism|more prominent in males]]. Some breeds have a [[mutation]] that causes extra feathering under the face, giving the appearance of a beard.<ref name=plosg>{{cite journal |last1=Guo |first1=Ying |last2=Gu |first2=Xiaorong |last3=Sheng |first3=Zheya |last4=Wang |first4=Yanqiang |last5=Luo |first5=Chenglong |last6=Liu |first6=Ranran |last7=Qu |first7=Hao |last8=Shu |first8=Dingming |last9=Wen |first9=Jie |last10=Crooijmans |first10=Richard P. M. A. |last11=Carlborg |first11=Örjan |last12=Zhao |first12=Yiqiang |last13=Hu |first13=Xiaoxiang |last14=Li |first14=Ning |display-authors=5 |title=A Complex Structural Variation on Chromosome 27 Leads to the Ectopic Expression of HOXB8 and the Muffs and Beard Phenotype in Chickens |journal=PLOS Genetics |volume=12 |issue=6 |date=June 2, 2016 |pmid=27253709 |pmc=4890787 |doi=10.1371/journal.pgen.1006071 |doi-access=free |article-number=e1006071}}</ref>
-Chickens are [[omnivore]]s.<ref>{{cite web |url=http://www.ideas-4-pets.co.uk/info.-on-chicken-care |title=Info on Chicken Care |access-date=August 13, 2008 |website=Ideas-4-pets.co.uk |year=2003 |archive-url=https://web.archive.org/web/20150625195044/http://www.ideas-4-pets.co.uk/info.-on-chicken-care |archive-date=June 25, 2015 |url-status=dead }}</ref> In the wild, they scratch at the soil to search for seeds, insects, and animals as large as [[lizard]]s, small snakes,<ref>{{cite web |url=https://www.youtube.com/watch?v=45i1hZfUQhk |archive-url=https://ghostarchive.org/varchive/youtube/20211211/45i1hZfUQhk| archive-date=December 11, 2021 |url-status=live|title=Chicken Kills Rattlesnake |last=D Lines |date=July 27, 2013 |access-date=March 13, 2019 |publisher=[[YouTube]]}}{{cbignore}}</ref> and young [[mouse|mice]].<ref>{{cite web |url=https://gworrell.freeyellow.com/chickenfaq.html |title=Frequently asked questions about chickens & eggs |access-date=August 13, 2008 |website=Gworrell.freeyellow.com |author=Gerard P.Worrell AKA "Farmer Jerry" |archive-url=https://web.archive.org/web/20080916202420/http://gworrell.freeyellow.com/chickenfaq.html |archive-date=September 16, 2008 |url-status=live }}</ref> A chicken may live for 5–10 years, depending on the [[breed]].<ref>{{cite web |url=http://www.ruleworks.co.uk/cgi-bin/TUfaq.exe?Guide=Poultry&Category=Poultry%20-%20General#q9 |title=The Poultry Guide – A to Z and FAQs |website=Ruleworks.co.uk |access-date=August 29, 2010 |archive-url=https://web.archive.org/web/20101128085141/http://ruleworks.co.uk/cgi-bin/TUfaq.exe?Guide=Poultry&Category=Poultry%20-%20General#q9 |archive-date=November 28, 2010 |url-status=dead }}</ref> The world's oldest known chicken lived for 16 years.<ref>{{cite web|last1=Smith |first1=Jamon |url=https://www.tuscaloosanews.com/article/DA/20060806/News/606120381/TL |title=World's oldest chicken starred in magic shows, was on 'Tonight Show' |archive-url=https://web.archive.org/web/20190220002804/https://www.tuscaloosanews.com/apps/pbcs.dll/article?AID=%2F20060806%2FNEWS%2F608060400%2F1007%2FNEWS02 |archive-date=February 20, 2019 |website=[[Tuscaloosa News]] |location=Alabama, USA |date=August 6, 2006 |access-date=May 18, 2020 |url-status=live}}</ref>
+Chickens are [[omnivore]]s.<ref>{{cite web |url=http://www.ideas-4-pets.co.uk/info.-on-chicken-care |title=Info on Chicken Care |access-date=August 13, 2008 |website=Ideas-4-pets.co.uk |year=2003 |archive-url=https://web.archive.org/web/20150625195044/http://www.ideas-4-pets.co.uk/info.-on-chicken-care |archive-date=June 25, 2015 }}</ref> In the wild, they scratch at the soil to search for seeds, insects, and animals as large as [[lizard]]s, small snakes,<ref>{{cite web |url=https://www.youtube.com/watch?v=45i1hZfUQhk |archive-url=https://ghostarchive.org/varchive/youtube/20211211/45i1hZfUQhk| archive-date=December 11, 2021 |url-status=live|title=Chicken Kills Rattlesnake |last=D Lines |date=July 27, 2013 |access-date=March 13, 2019 |publisher=[[YouTube]]}}{{cbignore}}</ref> and young [[mouse|mice]].<ref>{{cite web |url=https://gworrell.freeyellow.com/chickenfaq.html |title=Frequently asked questions about chickens & eggs |access-date=August 13, 2008 |website=Gworrell.freeyellow.com |author=Gerard P.Worrell AKA "Farmer Jerry" |archive-url=https://web.archive.org/web/20080916202420/http://gworrell.freeyellow.com/chickenfaq.html |archive-date=September 16, 2008 |url-status=live }}</ref> A chicken may live for 5–10 years, depending on the [[breed]].<ref>{{cite web |url=http://www.ruleworks.co.uk/cgi-bin/TUfaq.exe?Guide=Poultry&Category=Poultry%20-%20General#q9 |title=The Poultry Guide – A to Z and FAQs |website=Ruleworks.co.uk |access-date=August 29, 2010 |archive-url=https://web.archive.org/web/20101128085141/http://ruleworks.co.uk/cgi-bin/TUfaq.exe?Guide=Poultry&Category=Poultry%20-%20General#q9 |archive-date=November 28, 2010 }}</ref> The world's oldest known chicken lived for 16 years.<ref>{{cite web|last1=Smith |first1=Jamon |url=https://www.tuscaloosanews.com/article/DA/20060806/News/606120381/TL |title=World's oldest chicken starred in magic shows, was on 'Tonight Show' |archive-url=https://web.archive.org/web/20190220002804/https://www.tuscaloosanews.com/apps/pbcs.dll/article?AID=%2F20060806%2FNEWS%2F608060400%2F1007%2FNEWS02 |archive-date=February 20, 2019 |website=[[Tuscaloosa News]] |location=Alabama, USA |date=August 6, 2006 |access-date=May 18, 2020 |url-status=live}}</ref>
-Chickens are [[gregarious]], living in [[herd|flocks]], and [[Egg incubation|incubate eggs]] and raise young communally. Individual chickens dominate others, establishing a [[Dominance hierarchy|pecking order]]; dominant individuals take priority for access to food and nest sites. The concept of dominance, involving pecking, was described in female chickens by [[Thorleif Schjelderup-Ebbe]] in 1921 as the "pecking order".<ref>{{cite journal |last=Perrin |first=P. G. |year=1955 |title='Pecking order' 1927–54 |journal=American Speech |volume=30 |issue=4 |pages=265–268|doi=10.2307/453561 |jstor=453561 | issn = 0003-1283}}</ref><ref>{{cite book |last=Schjelderup-Ebbe |first=T. |year=1975 |chapter=Contributions to the social psychology of the domestic chicken [Schleidt M., Schleidt, W. M., translators] |editor-last=Schein |editor-first=M. W. |title=Social Hierarchy and Dominance. Benchmark Papers in Animal Behavior |volume=3 |location=Stroudsburg, Pennsylvania |publisher=Dowden, Hutchinson and Ross |pages=35–49}} (Reprinted from ''Zeitschrift für Psychologie'', 1922, 88:225–252.)</ref> Male chickens tend to leap and use their claws in conflicts.<ref>{{cite journal |last=Rajecki |first=D. W. |year=1988 |title=Formation of leap orders in pairs of male domestic chickens |journal=Aggressive Behavior |volume=14 |issue=6 |pages=425–436|doi=10.1002/1098-2337(1988)14:6<425::AID-AB2480140604>3.0.CO;2-#|s2cid=141664966 }}</ref> Chickens are capable of mobbing and killing a weak or inexperienced predator, such as a young fox.<ref>{{cite web |last=AFP |date=March 12, 2019 |title=Chickens 'teamed up to kill fox' at Brittany farming school |url=https://www.theguardian.com/world/2019/mar/12/chickens-teamed-up-to-kill-fox-at-brittany-farming-school |url-status=live |archive-url=https://web.archive.org/web/20190313002528/https://www.theguardian.com/world/2019/mar/12/chickens-teamed-up-to-kill-fox-at-brittany-farming-school |archive-date=March 13, 2019 |access-date=March 13, 2019 |website=Theguardian.com}}</ref>
+Chickens are [[gregarious]], living in [[herd|flocks]], and [[Egg incubation|incubate eggs]] and raise young communally. Individual chickens dominate others, establishing a [[Dominance hierarchy|pecking order]]; dominant individuals take priority for access to food and nest sites. The concept of dominance, involving pecking, was described in female chickens by [[Thorleif Schjelderup-Ebbe]] in 1921 as the "pecking order".<ref>{{cite journal |last=Perrin |first=P. G. |year=1955 |title='Pecking order' 1927–54 |journal=American Speech |volume=30 |issue=4 |pages=265–268|doi=10.2307/453561 |jstor=453561 | issn = 0003-1283}}</ref><ref>{{cite book |last=Schjelderup-Ebbe |first=T. |year=1975 |chapter=Contributions to the social psychology of the domestic chicken [Schleidt M., Schleidt, W. M., translators] |editor-last=Schein |editor-first=M. W. |title=Social Hierarchy and Dominance. Benchmark Papers in Animal Behavior |volume=3 |location=Stroudsburg, Pennsylvania |publisher=Dowden, Hutchinson and Ross |pages=35–49}} (Reprinted from ''Zeitschrift für Psychologie'', 1922, 88:225–252.)</ref> Male chickens tend to leap and use their claws in conflicts.<ref>{{cite journal |last=Rajecki |first=D. W. |year=1988 |title=Formation of leap orders in pairs of male domestic chickens |journal=Aggressive Behavior |volume=14 |issue=6 |pages=425–436|doi=10.1002/1098-2337(1988)14:6<425::AID-AB2480140604>3.0.CO;2-#|s2cid=141664966 }}</ref> Chickens are capable of mobbing and killing a weak or inexperienced predator, such as a young fox.<ref>{{cite web |last=AFP |date=March 12, 2019 |title=Chickens 'teamed up to kill fox' at Brittany farming school |url=https://www.theguardian.com/world/2019/mar/12/chickens-teamed-up-to-kill-fox-at-brittany-farming-school |url-status=live |archive-url=https://web.archive.org/web/20190313002528/https://www.theguardian.com/world/2019/mar/12/chickens-teamed-up-to-kill-fox-at-brittany-farming-school |archive-date=March 13, 2019 |access-date=March 13, 2019 |website=[[The Guardian]]}}</ref> Chickens have been thought of primarily as providers of food, but their [[cognition]], [[emotion]]s, and [[sociality]] are comparable with other birds and mammals.<ref name="Maring 2017">{{cite journal |last=Marino |first=Lori |title=Thinking chickens: a review of cognition, emotion, and behavior in the domestic chicken |journal=[[Animal Cognition]] |volume=20 |issue=2 |date=2017 |pmid=28044197 |pmc=5306232 |doi=10.1007/s10071-016-1064-4 |pages=127–147}}</ref>
-[[File:Rooster_crowing_small.ogv|thumb|Crowing (with audio)]]
+[[File:Rooster crowing small.ogv|thumb|Crowing (with audio)]]
 A male's crowing is a loud and sometimes shrill call, serving as a territorial signal to other males,<ref>{{Cite news |url=https://phys.org/news/2015-07-cock-roosters-crow.html |title=Top cock: Roosters crow in pecking order |website=Phys.org |access-date=January 14, 2018 |archive-url=https://web.archive.org/web/20180115124738/https://phys.org/news/2015-07-cock-roosters-crow.html |archive-date=January 15, 2018 |url-status=live }}</ref> and in response to sudden disturbances within their surroundings. Hens cluck loudly after laying an [[egg]] and to call their chicks. Chickens give different [[warning call]]s to indicate that a [[Predation|predator]] is approaching from the air or on the ground.<ref>{{cite journal |last1=Evans |first1=Christopher S. |last2=Evans |first2=Linda |last3=Marler |first3=Peter |title=On the meaning of alarm calls: functional reference in an avian vocal system |journal=Animal Behaviour |date=July 1993 |volume=46 |issue=1 |pages=23–38 |doi=10.1006/anbe.1993.1158 |s2cid=53165305 |s2cid-access=free }}</ref>
@@ Line 87: / Line 85: @@
 [[File:Red Junglefowl.jpg|thumb|[[Red junglefowl]], the wild ancestor of the chicken ]]
-Water or ground-dwelling fowl similar to modern [[partridge]]s, in the [[Galliformes]], the [[order (biology)|order]] of bird that chickens belong to, survived the [[Cretaceous–Paleogene extinction event]] that killed all tree-dwelling birds and their [[dinosaur]] relatives.<ref>{{cite journal |last=Pennisi |first=Elizabeth |author-link=Elizabeth Pennisi |title=Quaillike creatures were the only birds to survive the dinosaur-killing asteroid impact |journal=Science |date=May 24, 2018 |doi=10.1126/science.aau2802}}</ref> Chickens are descended primarily from the [[red junglefowl]] (''Gallus gallus'') and are scientifically classified as the same species.<ref name=nature>{{cite journal |title=A genetic variation map for chicken with 2.8 million single nucleotide polymorphisms |journal=Nature |date=December 9, 2004 |volume=432 |issue=7018 |pages=717–722 |doi=10.1038/nature03156 |pmid=15592405 |pmc=2263125 |bibcode=2004Natur.432..717B |last1=Wong |first1=G. K. |last2=Liu |first2=B. |last3=Wang |first3=J. |last4=Zhang |first4=Y. |last5=Yang |first5=X. |last6=Zhang |first6=Z. |last7=Meng |first7=Q. |last8=Zhou |first8=J. |last9=Li |first9=D. |last10=Zhang |first10=J. |last11=Ni |first11=P. |last12=Li |first12=S. |display-authors=6}}</ref> Domesticated chickens freely interbreed with populations of red junglefowl.<ref name=nature /> The domestic chicken has subsequently hybridised with [[grey junglefowl]], [[Sri Lankan junglefowl]] and [[green junglefowl]];<ref name="Lawal">{{cite journal |last1=Lawal |first1=Raman Akinyanju |last2=Martin |first2=Simon H. |last3=Vanmechelen |first3=Koen |last4=Vereijken |first4=Addie |last5=Silva |first5=Pradeepa |last6=Al-Atiyat |first6=Raed Mahmoud |last7=Aljumaah |first7=Riyadh Salah |last8=Mwacharo |first8=Joram M. |last9=Wu |first9=Dong-Dong |last10=Zhang |first10=Ya-Ping |last11=Hocking |first11=Paul M. |last12=Smith |first12=Jacqueline |last13=Wragg |first13=David |last14=Hanotte |first14=Olivier |display-authors=6 |title=The wild species genome ancestry of domestic chickens |journal=BMC Biology |date=December 2020 |volume=18 |issue=1 |pages=13 |doi=10.1186/s12915-020-0738-1 |pmid=32050971 |pmc=7014787 |doi-access=free}}</ref> a gene for yellow skin, for instance, was incorporated into domestic birds from the grey junglefowl (''G. sonneratii'').<ref>{{cite journal |last1=Eriksson |first1=Jonas |last2=Larson |first2=Greger |last3=Gunnarsson |first3=Ulrika |last4=Bed'hom |first4=Bertrand |last5=Tixier-Boichard |first5=Michele |last6=Strömstedt |first6=Lina |last7=Wright |first7=Dominic |last8=Jungerius |first8=Annemieke |last9=Vereijken |first9=Addie |last10=Randi |first10=Ettore |last11=Jensen |first11=Per |last12=Andersson |first12=Leif |display-authors=6 |title=Identification of the Yellow Skin Gene Reveals a Hybrid Origin of the Domestic Chicken |journal=PLOS Genetics |date=February 29, 2008 |volume=4 |issue=2 |pages=e1000010 |doi=10.1371/journal.pgen.1000010 |pmid=18454198 |pmc=2265484 |doi-access=free }}</ref> It is estimated that chickens share between 71 and 79% of their genome with red junglefowl.<ref name="Lawal"/>
+Water or ground-dwelling fowl similar to modern [[partridge]]s, in the [[Galliformes]], the [[order (biology)|order]] of bird that chickens belong to, survived the [[Cretaceous–Paleogene extinction event]] that killed all tree-dwelling birds and their [[dinosaur]] relatives.<ref>{{cite journal |last=Pennisi |first=Elizabeth |author-link=Elizabeth Pennisi |title=Quaillike creatures were the only birds to survive the dinosaur-killing asteroid impact |journal=Science |date=May 24, 2018 |doi=10.1126/science.aau2802}}</ref> Chickens are descended primarily from the [[red junglefowl]] (''Gallus gallus'') and are scientifically classified as the same species.<ref name=nature>{{cite journal |title=A genetic variation map for chicken with 2.8 million single nucleotide polymorphisms |journal=Nature |date=December 9, 2004 |volume=432 |issue=7018 |pages=717–722 |doi=10.1038/nature03156 |pmid=15592405 |pmc=2263125 |bibcode=2004Natur.432..717B |last1=Wong |first1=G. K. |last2=Liu |first2=B. |last3=Wang |first3=J. |last4=Zhang |first4=Y. |last5=Yang |first5=X. |last6=Zhang |first6=Z. |last7=Meng |first7=Q. |last8=Zhou |first8=J. |last9=Li |first9=D. |last10=Zhang |first10=J. |last11=Ni |first11=P. |last12=Li |first12=S. |display-authors=6}}</ref> Domesticated chickens freely interbreed with populations of red junglefowl.<ref name=nature /> The domestic chicken has subsequently hybridised with [[grey junglefowl]], [[Sri Lankan junglefowl]] and [[green junglefowl]];<ref name="Lawal">{{cite journal |last1=Lawal |first1=Raman Akinyanju |last2=Martin |first2=Simon H. |last3=Vanmechelen |first3=Koen |last4=Vereijken |first4=Addie |last5=Silva |first5=Pradeepa |last6=Al-Atiyat |first6=Raed Mahmoud |last7=Aljumaah |first7=Riyadh Salah |last8=Mwacharo |first8=Joram M. |last9=Wu |first9=Dong-Dong |last10=Zhang |first10=Ya-Ping |last11=Hocking |first11=Paul M. |last12=Smith |first12=Jacqueline |last13=Wragg |first13=David |last14=Hanotte |first14=Olivier |display-authors=6 |title=The wild species genome ancestry of domestic chickens |journal=BMC Biology |date=December 2020 |volume=18 |issue=1 |page=13 |doi=10.1186/s12915-020-0738-1 |pmid=32050971 |pmc=7014787 |doi-access=free}}</ref> a gene for yellow skin, for instance, was incorporated into domestic birds from the grey junglefowl (''G. sonneratii'').<ref>{{cite journal |last1=Eriksson |first1=Jonas |last2=Larson |first2=Greger |last3=Gunnarsson |first3=Ulrika |last4=Bed'hom |first4=Bertrand |last5=Tixier-Boichard |first5=Michele |last6=Strömstedt |first6=Lina |last7=Wright |first7=Dominic |last8=Jungerius |first8=Annemieke |last9=Vereijken |first9=Addie |last10=Randi |first10=Ettore |last11=Jensen |first11=Per |last12=Andersson |first12=Leif |display-authors=6 |title=Identification of the Yellow Skin Gene Reveals a Hybrid Origin of the Domestic Chicken |journal=PLOS Genetics |date=February 29, 2008 |volume=4 |issue=2 |article-number=e1000010 |doi=10.1371/journal.pgen.1000010 |pmid=18454198 |pmc=2265484 |doi-access=free }}</ref> It is estimated that chickens share between 71 and 79% of their genome with red junglefowl.<ref name="Lawal"/>
 === Domestication ===
@@ Line 93: / Line 91: @@
 {{further|Domestication}}
-[[File:Chicken domestication and dispersal.svg|thumb|upright=2|Chicken domestication and dispersal;<ref name="Lawal"/> possibility of early arrival in Americas<ref name="Borrell 2007"/><ref name="Storey 2007"/>]]
+<!--[[File:Chicken domestication and dispersal.svg|thumb|upright=2|Chicken domestication and dispersal;<ref name="Lawal"/> possibility of early arrival in Americas<ref name="Borrell 2007"/><ref name="Storey 2007"/>]]
+-->
+According to one early study, a single domestication event of the [[red junglefowl]] in present-day [[Thailand]] gave rise to the modern chicken with minor transitions separating the modern breeds.<ref name="oneMatriarch">{{citation |title=One subspecies of the red junglefowl (Gallus gallus gallus) suffices as the matriarchic ancestor of all domestic breeds |first1=A. |last1=Fumihito |first2=T. |last2=Miyake |first3=S. |last3=Sumi |first4=M. |last4=Takada |first5=S. |last5=Ohno |first6=N. |last6=Kondo |journal=PNAS |date=December 20, 1994 |volume=91 |number=26 |pages=12505–12509 |doi=10.1073/pnas.91.26.12505 |pmid=7809067 |bibcode=1994PNAS...9112505F |pmc=45467 |doi-access=free }}</ref> The red junglefowl is well adapted to take advantage of the vast quantities of seed produced during the end of the [[Bamboo#Mass flowering|multi-decade bamboo seeding cycle]], to boost its own reproduction.<ref>{{citation |first=Rick |last=King |title=Rat Attack |date=February 24, 2009 |journal=Nova and National Geographic Television |url=https://www.pbs.org/wgbh/nova/nature/rat-attack.html |access-date=August 25, 2017 |archive-url=https://web.archive.org/web/20170823151419/http://www.pbs.org/wgbh/nova/nature/rat-attack.html |archive-date=August 23, 2017 |url-status=live }}</ref> In domesticating the chicken, humans took advantage of the red junglefowl's ability to reproduce prolifically when exposed to a surge in its food supply.<ref>{{citation |first=Rick |last=King |title=Plant vs. Predator |date=February 1, 2009 |journal=NOVA |url=https://www.pbs.org/wgbh/nova/article/plant-vs-predator/ |access-date=August 25, 2017 |archive-url=https://web.archive.org/web/20170821123509/http://www.pbs.org/wgbh/nova/nature/plant-vs-predator.html |archive-date=August 21, 2017 |url-status=live }}</ref>
-According to one early study, a single domestication event of the [[red junglefowl]] in present-day [[Thailand]] gave rise to the modern chicken with minor transitions separating the modern breeds.<ref name="oneMatriarch">{{citation |title=One subspecies of the red junglefowl (Gallus gallus gallus) suffices as the matriarchic ancestor of all domestic breeds |first1=A. |last1=Fumihito |first2=T. |last2=Miyake |first3=S. |last3=Sumi |first4=M. |last4=Takada |first5=S. |last5=Ohno |first6=N. |last6=Kondo |journal=PNAS |date=December 20, 1994 |volume=91 |number=26 |pages=12505–12509 |doi=10.1073/pnas.91.26.12505 |pmid=7809067 |bibcode=1994PNAS...9112505F |pmc=45467 |doi-access=free }}</ref> The red junglefowl is well adapted to take advantage of the vast quantities of seed produced during the end of the [[Bamboo#Mass flowering|multi-decade bamboo seeding cycle]], to boost its own reproduction.<ref>{{citation |first=Rick |last=King |title=Rat Attack |date=February 24, 2009 |journal=Nova and National Geographic Television |url=https://www.pbs.org/wgbh/nova/nature/rat-attack.html |access-date=August 25, 2017 |archive-url=https://web.archive.org/web/20170823151419/http://www.pbs.org/wgbh/nova/nature/rat-attack.html |archive-date=August 23, 2017 |url-status=live }}</ref> In domesticating the chicken, humans took advantage of the red junglefowl's ability to reproduce prolifically when exposed to a surge in its food supply.<ref>{{citation |first=Rick |last=King |title=Plant vs. Predator |date=February 1, 2009 |journal=NOVA |url=https://www.pbs.org/wgbh/nova/nature/plant-vs-predator.html |access-date=August 25, 2017 |archive-url=https://web.archive.org/web/20170821123509/http://www.pbs.org/wgbh/nova/nature/plant-vs-predator.html |archive-date=August 21, 2017 |url-status=live }}</ref>
+Exactly when and where the chicken was domesticated was controversial. Genomic studies estimated that the chicken was domesticated 8,000 years ago<ref name="Lawal"/> in Southeast Asia and spread to China and India 2,000 to 3,000 years later. Archaeological evidence appeared to support domestic chickens in Southeast Asia well before 6000 BC, China by 6000 BC and India by 2000 BC.<ref name=Lawal/><ref name="West Zhou 1988">{{cite journal |last1=West |first1=B. |last2=Zhou |first2=B.X. |year=1988 |title=Did chickens go north? New evidence for domestication |journal=J. Archaeol. Sci. |volume=14 |issue= 5 |pages=515–533 |doi=10.1016/0305-4403(88)90080-5 |bibcode=1988JArSc..15..515W }}</ref><ref>{{cite journal |last1=Al-Nasser |first1=A. |last2=Al-Khalaifa |first2=H. |last3=Al-Saffar |first3=A. |last4=Khalil |first4=F. |last5=Albahouh |first5=M. |last6=Ragheb |first6=G. |last7=Al-Haddad |first7=A. |last8=Mashaly |first8=M. |title=Overview of chicken taxonomy and domestication |journal=World's Poultry Science Journal |date=June 1, 2007 |volume=63 |issue=2 |pages=285–300 |doi=10.1017/S004393390700147X |s2cid=86734013 }}</ref> A landmark 2020 ''Nature'' study that fully sequenced 863 chickens across the world suggests that all domestic chickens originate from a single domestication event of red junglefowl (''[[Gallus gallus]]'') whose present-day distribution is predominantly in southeast Asia. These domesticated chickens spread across Southeast and South Asia where they interbred with local wild species of junglefowl, forming genetically and geographically distinct groups. Analysis of the most popular commercial breed shows that the White Leghorn breed possesses a mosaic of divergent ancestries inherited from subspecies of red junglefowl.<ref>{{cite journal |title=863 genomes reveal the origin and domestication of chicken |year=2020 |doi=10.1038/s41422-020-0349-y |s2cid=220050312 |last1=Wang |first1=Ming-Shan |last2=Thakur|first2=Mukesh |last3=Peng |first3=Min-Sheng |last4=Jiang |first4=Yu |last5=Frantz |first5=Laurent Alain François |last6=Li|first6=Ming |last7=Zhang|first7=Jin-Jin |last8=Wang |first8=Sheng |last9=Peters |first9=Joris |last10=Otecko |first10=Newton Otieno |last11=Suwannapoom |first11=Chatmongkon |last12=Guo |first12=Xing |journal=Cell Research |volume=30 |issue=8 |pages=693–701 |pmid=32581344 |pmc=7395088 |display-authors=6}}</ref><ref>{{cite journal |last1=Liu |first1=Yi-Ping |last2=Wu |first2=Gui-Sheng |last3=Yao |first3=Yong-Gang |last4=Miao |first4=Yong-Wang |last5=Luikart |first5=Gordon |last6=Baig |first6=Mumtaz |last7=Beja-Pereira |first7=Albano |last8=Ding |first8=Zhao-Li |last9=Palanichamy |first9=Malliya Gounder |last10=Zhang |first10=Ya-Ping |display-authors=6 |title=Multiple maternal origins of chickens: Out of the Asian jungles |journal=Molecular Phylogenetics and Evolution |date=January 2006 |volume=38 |issue=1 |pages=12–19 |doi=10.1016/j.ympev.2005.09.014 |pmid=16275023 |bibcode=2006MolPE..38...12L }}</ref><ref>{{cite journal |last1=Zeder |first1=Melinda A. |last2=Emshwiller |first2=Eve |last3=Smith |first3=Bruce D. |last4=Bradley |first4=Daniel G. |title=Documenting domestication: the intersection of genetics and archaeology |journal=Trends in Genetics |date=March 2006 |volume=22 |issue=3 |pages=139–155 |doi=10.1016/j.tig.2006.01.007 |pmid=16458995 }}</ref>
-Exactly when and where the chicken was domesticated remains controversial. Genomic studies estimate that the chicken was domesticated 8,000 years ago<ref name="Lawal"/> in Southeast Asia and spread to China and India 2,000 to 3,000 years later. Archaeological evidence supports domestic chickens in Southeast Asia well before 6000&nbsp;BC, China by 6000&nbsp;BC and India by 2000&nbsp;BC.<ref name=Lawal/><ref name="West Zhou 1988">{{cite journal |last1=West |first1=B. |last2=Zhou |first2=B.X. |year=1988 |title=Did chickens go north? New evidence for domestication |journal=J. Archaeol. Sci. |volume=14 |issue= 5 |pages=515–533 |doi=10.1016/0305-4403(88)90080-5 |bibcode=1988JArSc..15..515W }}</ref><ref>{{cite journal |last1=Al-Nasser |first1=A. |last2=Al-Khalaifa |first2=H. |last3=Al-Saffar |first3=A. |last4=Khalil |first4=F. |last5=Albahouh |first5=M. |last6=Ragheb |first6=G. |last7=Al-Haddad |first7=A. |last8=Mashaly |first8=M. |title=Overview of chicken taxonomy and domestication |journal=World's Poultry Science Journal |date=June 1, 2007 |volume=63 |issue=2 |pages=285–300 |doi=10.1017/S004393390700147X |s2cid=86734013 }}</ref> A landmark 2020 Nature study that fully sequenced 863 chickens across the world suggests that all domestic chickens originate from a single domestication event of red junglefowl whose present-day distribution is predominantly in southwestern China, northern Thailand and Myanmar. These domesticated chickens spread across Southeast and South Asia where they interbred with local wild species of junglefowl, forming genetically and geographically distinct groups. Analysis of the most popular commercial breed shows that the White Leghorn breed possesses a mosaic of divergent ancestries inherited from subspecies of red junglefowl.<ref>{{cite journal |title=863 genomes reveal the origin and domestication of chicken |year=2020 |doi=10.1038/s41422-020-0349-y |s2cid=220050312 |last1=Wang |first1=Ming-Shan |last2=Thakur|first2=Mukesh |last3=Peng |first3=Min-Sheng |last4=Jiang |first4=Yu |last5=Frantz |first5=Laurent Alain François |last6=Li|first6=Ming |last7=Zhang|first7=Jin-Jin |last8=Wang |first8=Sheng |last9=Peters |first9=Joris |last10=Otecko |first10=Newton Otieno |last11=Suwannapoom |first11=Chatmongkon |last12=Guo |first12=Xing |journal=Cell Research |volume=30 |issue=8 |pages=693–701 |pmid=32581344 |pmc=7395088 |display-authors=6}}</ref><ref>{{cite journal |last1=Liu |first1=Yi-Ping |last2=Wu |first2=Gui-Sheng |last3=Yao |first3=Yong-Gang |last4=Miao |first4=Yong-Wang |last5=Luikart |first5=Gordon |last6=Baig |first6=Mumtaz |last7=Beja-Pereira |first7=Albano |last8=Ding |first8=Zhao-Li |last9=Palanichamy |first9=Malliya Gounder |last10=Zhang |first10=Ya-Ping |display-authors=6 |title=Multiple maternal origins of chickens: Out of the Asian jungles |journal=Molecular Phylogenetics and Evolution |date=January 2006 |volume=38 |issue=1 |pages=12–19 |doi=10.1016/j.ympev.2005.09.014 |pmid=16275023 |bibcode=2006MolPE..38...12L }}</ref><ref>{{cite journal |last1=Zeder |first1=Melinda A. |last2=Emshwiller |first2=Eve |last3=Smith |first3=Bruce D. |last4=Bradley |first4=Daniel G. |title=Documenting domestication: the intersection of genetics and archaeology |journal=Trends in Genetics |date=March 2006 |volume=22 |issue=3 |pages=139–155 |doi=10.1016/j.tig.2006.01.007 |pmid=16458995 }}</ref>
+Re-examination of bones from over 600 sites, and dating of those from 23 sites, identified the earliest probable chicken bones as from central Thailand, at [[Ban Non Wat]], some 3,250 years ago. The paleo-anatomist Joris Peters and the [[Bioarchaeology|bioarchaeologist]] Greger Larson state that this coincided with the growing of rice, and propose that wild jungle fowl were attracted to eat the [[rice]] seeds, nested nearby, and became domesticated. Skeletons of birds in the ''Gallus'' genus were used as grave goods at the site, confirming domestication.<ref name="Peters 2022">{{cite journal |last1=Peters |first1=Joris |last2=Lebrasseur |first2=Ophélie |last3=Irving-Pease |first3=Evan K. |last4=Paxinos |first4=Ptolemaios Dimitrios |last5=Best |first5=Julia |last6=Smallman |first6=Riley |last7=Callou |first7=Cécile |last8=Gardeisen |first8=Armelle |last9=Trixl |first9=Simon |last10=Frantz |first10=Laurent |last11=Sykes |first11=Naomi |last12=Fuller |first12=Dorian Q. |last13=Larson |first13=Greger |display-authors=5 |title=The biocultural origins and dispersal of domestic chickens |journal=Proceedings of the National Academy of Sciences |volume=119 |issue=24 |date=June 14, 2022 |pmid=35666876 |pmc=9214543 |doi=10.1073/pnas.2121978119 |doi-access=free}}</ref>
 == Dispersal ==
@@ Line 105: / Line 105: @@
 [[File:Map showing prehistoric diffusion of domestic chickens (Gallus gallus) into the Pacific via the Austronesian migrations (Thomson, Lebrasseur, & Austin, 2014).png|thumb|upright=2|Prehistoric introduction of domesticated chickens into [[Oceania]] from the [[Philippines]] via [[Neolithic]] [[Austronesian expansion]] (starting at c. 4000 [[Before present|BP]]), inferred from genetic markers on ancient and modern chicken DNA (Thomson ''et al.'', 2014)<ref name="Thomson"/>]]
-A word for the domestic chicken (''*manuk'') is part of the reconstructed [[Proto-Austronesian language]], indicating they were [[Domesticated plants and animals of Austronesia|domesticated]] by the [[Austronesian peoples]] since ancient times. Chickens, together with dogs and pigs, were carried throughout the entire range of the prehistoric Austronesian maritime migrations to [[Island Southeast Asia]], [[Micronesia]], [[Island Melanesia]], [[Polynesia]], and [[Madagascar]], starting from at least 3000&nbsp;BC from [[Indigenous Taiwanese|Taiwan]].<ref name= Thomson>{{cite journal |last=Thomson |first=Vicki A. |others= et al. |title=Using ancient DNA to study the origins and dispersal of ancestral Polynesian chickens across the Pacific |journal=Proceedings of the National Academy of Sciences |date=April 2014 |volume=111 |issue=13 |pages=4826–4831 |doi=10.1073/pnas.1320412111 |pmid=24639505 |pmc=3977275 |bibcode=2014PNAS..111.4826T |doi-access=free }}</ref><ref name= Piper>{{cite book |first1=Philip J. |last1=Piper |editor1-first=Philip J. |editor1-last=Piper |editor2-first=Hirofumi |editor2-last=Matsumura |editor3-first=David |editor3-last=Bulbeck |title=New Perspectives in Southeast Asian and Pacific Prehistory |chapter=The Origins and Arrival of the Earliest Domestic Animals in Mainland and Island Southeast Asia: A Developing Story of Complexity |publisher=[[ANU Press]] |volume=45 |series=terra australis |year=2017 |isbn=9781760460945 |chapter-url =http://press-files.anu.edu.au/downloads/press/n2320/html/ch15.xhtml |access-date =May 5, 2023 |archive-date =November 28, 2022 |archive-url =https://web.archive.org/web/20221128075413/https://press-files.anu.edu.au/downloads/press/n2320/html/ch15.xhtml |url-status =live}}</ref><ref>{{cite book |url=https://books.google.com/books?id=FJ9ULYwX3zgC&pg=PA56 |title=The Cambridge History of the Pacific Islanders |first=Malama |last=Meleisea |date=March 25, 2004 |publisher=[[Cambridge University Press]] |page=56 |access-date=March 13, 2019 |archive-url=https://web.archive.org/web/20160913140948/https://books.google.com/books?id=FJ9ULYwX3zgC&pg=PA56 |archive-date=September 13, 2016 |url-status=live |isbn=9780521003544}}</ref><ref>{{cite book |url=https://books.google.com/books?id=tlSspaBLkhoC&pg=PA411 |title=Anthropological Genetics: Theory, Methods and Applications |first=Michael H. |last=Crawford |date=March 13, 2019 |publisher=[[Cambridge University Press]] |page=411 |access-date=March 13, 2019 |via=Google Books |archive-url=https://web.archive.org/web/20160913143140/https://books.google.com/books?id=tlSspaBLkhoC&pg=PA411 |archive-date=September 13, 2016 |url-status=live |isbn=9780521546973}}</ref> These chickens may have been introduced during [[pre-Columbian]] times to [[South America]] via [[Polynesians|Polynesian]] seafarers, but this is disputed.<ref name= Neumann>{{cite news |last=Neumann |first=Scott |title=Study: The Chicken Didn't Cross The Pacific To South America |url=https://www.npr.org/sections/thetwo-way/2014/03/18/291182073/study-the-chicken-didnt-cross-the-pacific-to-south-america |access-date=May 5, 2023 |work=The Two Way |agency=NPR |date=March 18, 2014 |archive-date=May 5, 2023 |archive-url=https://web.archive.org/web/20230505060006/https://www.npr.org/sections/thetwo-way/2014/03/18/291182073/study-the-chicken-didnt-cross-the-pacific-to-south-america |url-status=live }}</ref>
+A word for the domestic chicken (''*manuk'') is part of the reconstructed [[Proto-Austronesian language]], indicating they were [[Domesticated plants and animals of Austronesia|domesticated]] by the [[Austronesian peoples]] since ancient times. Chickens, together with dogs and pigs, were carried throughout the entire range of the prehistoric Austronesian maritime migrations to [[Island Southeast Asia]], [[Micronesia]], [[Island Melanesia]], [[Polynesia]], and [[Madagascar]], starting from at least 3000&nbsp;BC from [[Indigenous Taiwanese|Taiwan]].<ref name= Thomson>{{cite journal |last=Thomson |first=Vicki A. |others= et al. |title=Using ancient DNA to study the origins and dispersal of ancestral Polynesian chickens across the Pacific |journal=Proceedings of the National Academy of Sciences |date=April 2014 |volume=111 |issue=13 |pages=4826–4831 |doi=10.1073/pnas.1320412111 |pmid=24639505 |pmc=3977275 |bibcode=2014PNAS..111.4826T |doi-access=free }}</ref><ref name= Piper>{{cite book |first1=Philip J. |last1=Piper |editor1-first=Philip J. |editor1-last=Piper |editor2-first=Hirofumi |editor2-last=Matsumura |editor3-first=David |editor3-last=Bulbeck |title=New Perspectives in Southeast Asian and Pacific Prehistory |chapter=The Origins and Arrival of the Earliest Domestic Animals in Mainland and Island Southeast Asia: A Developing Story of Complexity |publisher=[[ANU Press]] |volume=45 |series=terra australis |year=2017 |isbn=978-1-76046-094-5 |chapter-url =http://press-files.anu.edu.au/downloads/press/n2320/html/ch15.xhtml |access-date =May 5, 2023 |archive-date =November 28, 2022 |archive-url =https://web.archive.org/web/20221128075413/https://press-files.anu.edu.au/downloads/press/n2320/html/ch15.xhtml |url-status =live}}</ref><ref>{{cite book |url=https://books.google.com/books?id=FJ9ULYwX3zgC&pg=PA56 |title=The Cambridge History of the Pacific Islanders |first=Malama |last=Meleisea |date=March 25, 2004 |publisher=[[Cambridge University Press]] |page=56 |access-date=March 13, 2019 |archive-url=https://web.archive.org/web/20160913140948/https://books.google.com/books?id=FJ9ULYwX3zgC&pg=PA56 |archive-date=September 13, 2016 |url-status=live |isbn=978-0-521-00354-4}}</ref><ref>{{cite book |url=https://books.google.com/books?id=tlSspaBLkhoC&pg=PA411 |title=Anthropological Genetics: Theory, Methods and Applications |first=Michael H. |last=Crawford |date=March 13, 2019 |publisher=[[Cambridge University Press]] |page=411 |access-date=March 13, 2019 |via=Google Books |archive-url=https://web.archive.org/web/20160913143140/https://books.google.com/books?id=tlSspaBLkhoC&pg=PA411 |archive-date=September 13, 2016 |url-status=live |isbn=978-0-521-54697-3}}</ref> These chickens may have been introduced during [[pre-Columbian]] times to [[South America]] via [[Polynesians|Polynesian]] seafarers, but this is disputed.<ref name= Neumann>{{cite news |last=Neumann |first=Scott |title=Study: The Chicken Didn't Cross The Pacific To South America |url=https://www.npr.org/sections/thetwo-way/2014/03/18/291182073/study-the-chicken-didnt-cross-the-pacific-to-south-america |access-date=May 5, 2023 |work=The Two Way |agency=NPR |date=March 18, 2014 |archive-date=May 5, 2023 |archive-url=https://web.archive.org/web/20230505060006/https://www.npr.org/sections/thetwo-way/2014/03/18/291182073/study-the-chicken-didnt-cross-the-pacific-to-south-america |url-status=live }}</ref>
+=== Africa ===
+Chickens reached Egypt via the [[Middle East]] for purposes of [[cockfighting]] about 1400&nbsp;BC and became widely bred in Egypt around 300&nbsp;BC.<ref name="CHOF"/> Three possible routes of introduction into Africa around the early first millennium AD could have been through the Egyptian [[Nile River|Nile]] Valley, the East Africa Roman-Greek or Indian trade, or from [[Carthage]] and the [[Berbers]], across the [[Sahara Desert|Sahara]]. The earliest known remains are from [[Mali]], [[Nubia]], East Coast, and [[South Africa]] and date back to the middle of the first millennium AD.<ref name= CHOF/>
 === Americas ===
-The possibility that domestic chickens were in the Americas before Western contact is debated by researchers, but blue-egged chickens, found only in the Americas and Asia, suggest an Asian origin for early American chickens. A lack of data from Thailand, Russia, the Indian subcontinent, Southeast Asia and Sub-Saharan Africa makes it difficult to lay out a clear map of the spread of chickens in these areas; better description and genetic analysis of local breeds threatened by [[extinction]] may also help with research into this area.<ref name= CHOF/> Chicken bones from the [[Arauco Peninsula]] in [[Zona Sur|south-central Chile]] were radiocarbon dated as pre-Columbian, and DNA analysis suggested they were related to prehistoric populations in Polynesia.<ref name="Borrell 2007">{{cite journal |last1=Borrell |first1=Brendan |title=DNA reveals how the chicken crossed the sea |journal=Nature |date=June 1, 2007 |volume=447 |issue=7145 |pages=620–621 |doi=10.1038/447620b |pmid=17554271 |bibcode=2007Natur.447R.620B |s2cid=4418786 |doi-access=free }}</ref><ref name="Storey 2007">{{cite journal |last=Storey |first=A. A. |others= et al. |title=Radiocarbon and DNA evidence for a pre-Columbian introduction of Polynesian chickens to Chile |journal=Proceedings of the National Academy of Sciences |date=June 19, 2007 |volume=104 |issue=25 |pages=10335–10339 |doi=10.1073/pnas.0703993104 |pmid=17556540 |pmc=1965514 |bibcode=2007PNAS..10410335S |doi-access=free }}</ref> However, further study of the same bones cast doubt on the findings.<ref>{{cite journal |last=Gongora |first=Jaime |others= et al. |year=2008 |title=Indo-European and Asian origins for Chilean and Pacific chickens revealed by mtDNA |journal=PNAS |volume=105 |issue=30 |pages=10308–10313 |doi=10.1073/pnas.0801991105 |pmid=18663216 |pmc=2492461 |bibcode=2008PNAS..10510308G |doi-access=free }}</ref><ref name= Thomson14>{{cite journal |last=Thomson |first=Vicki A.
+The possibility that domestic chickens were in the Americas before Western contact is debated by researchers, but blue-egged chickens, found only in the Americas and Asia, suggest an Asian origin for early American chickens. A lack of data from Thailand, Russia, the [[Indian subcontinent]], Southeast Asia and [[Sub-Saharan Africa]] makes it difficult to lay out a clear map of the spread of chickens in these areas; better description and genetic analysis of local breeds threatened by [[extinction]] may also help with research into this area.<ref name= CHOF/> Chicken bones from the [[Arauco Peninsula]] in [[Zona Sur|south-central Chile]] were [[Radiocarbon dating|radiocarbon dated]] as [[Pre-Columbian era|pre-Columbian]], and [[DNA]] analysis suggested they were related to prehistoric populations in Polynesia.<ref name="Borrell 2007">{{cite journal |last1=Borrell |first1=Brendan |title=DNA reveals how the chicken crossed the sea |journal=[[Nature (journal)|Nature]] |date=June 1, 2007 |volume=447 |issue=7145 |pages=620–621 |doi=10.1038/447620b |pmid=17554271 |bibcode=2007Natur.447R.620B |s2cid=4418786 |doi-access=free }}</ref><ref name="Storey 2007">{{cite journal |last=Storey |first=A. A. |others= et al. |title=Radiocarbon and DNA evidence for a pre-Columbian introduction of Polynesian chickens to Chile |journal=[[PNAS]] |date=June 19, 2007 |volume=104 |issue=25 |pages=10335–10339 |doi=10.1073/pnas.0703993104 |pmid=17556540 |pmc=1965514 |bibcode=2007PNAS..10410335S |doi-access=free }}</ref> However, further study of the same bones cast doubt on the findings.<ref>{{cite journal |last=Gongora |first=Jaime |others= et al. |year=2008 |title=Indo-European and Asian origins for Chilean and Pacific chickens revealed by mtDNA |journal=[[PNAS]] |volume=105 |issue=30 |pages=10308–10313 |doi=10.1073/pnas.0801991105 |pmid=18663216 |pmc=2492461 |bibcode=2008PNAS..10510308G |doi-access=free }}</ref><ref name= Thomson14>{{cite journal |last=Thomson |first=Vicki A.
-|others= et al. |title=Using ancient DNA to study the origins and dispersal of ancestral Polynesian chickens across the Pacific |journal=Proceedings of the National Academy of Sciences |date=April 1, 2014 |volume=111 |issue=13 |pages=4826–4831 |doi=10.1073/pnas.1320412111 |pmid=24639505 |pmc=3977275 |bibcode=2014PNAS..111.4826T |doi-access=free }}</ref>
+|others= et al. |title=Using ancient DNA to study the origins and dispersal of ancestral Polynesian chickens across the Pacific |journal=[[PNAS]] |date=April 1, 2014 |volume=111 |issue=13 |pages=4826–4831 |doi=10.1073/pnas.1320412111 |pmid=24639505 |pmc=3977275 |bibcode=2014PNAS..111.4826T |doi-access=free }}</ref>
 === Eurasia ===
-Chicken remains have been difficult to date, given the small and fragile bird bones; this may account for discrepancies in dates given by different sources. Archaeological evidence is supplemented by mentions in historical texts from the last few centuries BC, and by depictions in prehistoric artworks, such as across Central Asia.<ref name= Peters24>{{cite journal |last=Peters |first=Carli |others= et al. |title= Archaeological and molecular evidence for ancient chickens in Central Asia |journal= Nature Communications |volume=15 |issue=1 |date=April 2, 2024 |page=2697 |issn=2041-1723 |pmid=38565545 |pmc=10987595 |doi=10.1038/s41467-024-46093-2|bibcode=2024NatCo..15.2697P }}</ref> Chickens were widespread throughout southern Central Asia by the 4th century BC.<ref name= Peters24/>
+Chicken remains have been difficult to date, given the small and fragile bird bones; this may account for discrepancies in dates given by different sources. Archaeological evidence is supplemented by mentions in historical texts from the last few centuries BC, and by depictions in prehistoric artworks, such as across Central Asia.<ref name= Peters24>{{cite journal |last=Peters |first=Carli |others= et al. |title= Archaeological and molecular evidence for ancient chickens in Central Asia |journal= Nature Communications |volume=15 |issue=1 |date=April 2, 2024 |article-number=2697 |issn=2041-1723 |pmid=38565545 |pmc=10987595 |doi=10.1038/s41467-024-46093-2|bibcode=2024NatCo..15.2697P }}</ref> Chickens were widespread throughout southern Central Asia by the 4th century BC.<ref name= Peters24/>
-Middle Eastern chicken remains go back to a little earlier than 2000&nbsp;BC in [[Syria (region)|Syria]].<ref name="CHOF">The Cambridge History of Food, 2000, [[Cambridge University Press]], Vol. 1, pp. 496–499</ref> Phoenicians spread chickens along the Mediterranean coasts as far as Iberia. During the [[Hellenistic period]] (4th–2nd centuries BC), in the southern [[Levant]], chickens began to be widely domesticated for food.<ref name= pmid26195775>{{cite journal |last1=Perry-Gal |first1=Lee |last2=Erlich |first2=Adi |last3=Gilboa |first3=Ayelet |last4=Bar-Oz |first4=Guy |date=August 11, 2015 |title=Earliest economic exploitation of chicken outside East Asia: Evidence from the Hellenistic Southern Levant |journal=Proceedings of the National Academy of Sciences |volume=112 |issue=32 |pages=9849–9854 |bibcode=2015PNAS..112.9849P |doi=10.1073/pnas.1504236112 |pmc=4538678 |pmid=26195775 |doi-access=free}}</ref> The first pictures of chickens in Europe are found on [[Corinth, Greece|Corinthian]] [[pottery]] of the 7th century BC.<ref>{{cite book |url=https://books.google.com/books?id=NrIapgM4LwQC&pg=PA176 |title=Regional Greek Cooking |first1=Dean |last1=Karayanis |first2=Catherine |last2=Karayanis |date=March 13, 2019 |publisher=[[Hippocrene Books]] |page=176 |access-date=March 13, 2019 |via=Google Books |archive-url=https://web.archive.org/web/20160913141141/https://books.google.com/books?id=NrIapgM4LwQC&pg=PA176 |archive-date=September 13, 2016 |url-status=live |isbn=9780781811460}}</ref><ref>{{cite book |url=https://books.google.com/books?id=Xwq1lunLkuoC&pg=PA207 |title=Cooking with the Bible: Biblical Food, Feasts, and Lore |first1=Anthony F. |last1=Chiffolo |first2=Rayner W. |last2=Hesse |date=March 13, 2019 |publisher=[[Greenwood Publishing Group]] |page=207 |access-date=March 13, 2019 |via=Google Books |archive-url=https://web.archive.org/web/20160913080305/https://books.google.com/books?id=Xwq1lunLkuoC&pg=PA207 |archive-date=September 13, 2016 |url-status=live |isbn=9780313334108}}</ref>
+Middle Eastern chicken remains go back to a little earlier than 2000&nbsp;BC in [[Syria (region)|Syria]].<ref name="CHOF">The Cambridge History of Food, 2000, [[Cambridge University Press]], Vol. 1, pp. 496–499</ref> Phoenicians spread chickens along the Mediterranean coasts as far as Iberia. During the [[Hellenistic period]] (4th–2nd centuries BC), in the southern [[Levant]], chickens began to be widely domesticated for food.<ref name= pmid26195775>{{cite journal |last1=Perry-Gal |first1=Lee |last2=Erlich |first2=Adi |last3=Gilboa |first3=Ayelet |last4=Bar-Oz |first4=Guy |date=August 11, 2015 |title=Earliest economic exploitation of chicken outside East Asia: Evidence from the Hellenistic Southern Levant |journal=Proceedings of the National Academy of Sciences |volume=112 |issue=32 |pages=9849–9854 |bibcode=2015PNAS..112.9849P |doi=10.1073/pnas.1504236112 |pmc=4538678 |pmid=26195775 |doi-access=free}}</ref> The first pictures of chickens in Europe are found on [[Corinth, Greece|Corinthian]] [[pottery]] of the 7th century BC.<ref>{{cite book |url=https://books.google.com/books?id=NrIapgM4LwQC&pg=PA176 |title=Regional Greek Cooking |first1=Dean |last1=Karayanis |first2=Catherine |last2=Karayanis |date=March 13, 2019 |publisher=[[Hippocrene Books]] |page=176 |access-date=March 13, 2019 |via=Google Books |archive-url=https://web.archive.org/web/20160913141141/https://books.google.com/books?id=NrIapgM4LwQC&pg=PA176 |archive-date=September 13, 2016 |url-status=live |isbn=978-0-7818-1146-0}}</ref><ref>{{cite book |url=https://books.google.com/books?id=Xwq1lunLkuoC&pg=PA207 |title=Cooking with the Bible: Biblical Food, Feasts, and Lore |first1=Anthony F. |last1=Chiffolo |first2=Rayner W. |last2=Hesse |date=March 13, 2019 |publisher=[[Greenwood Publishing Group]] |page=207 |access-date=March 13, 2019 |via=Google Books |archive-url=https://web.archive.org/web/20160913080305/https://books.google.com/books?id=Xwq1lunLkuoC&pg=PA207 |archive-date=September 13, 2016 |url-status=live |isbn=978-0-313-33410-8}}</ref>
 Breeding increased under the [[Roman Empire]] and reduced in the [[Middle Ages]].<ref name= CHOF/> [[DNA sequencing|Genetic sequencing]] of chicken bones from archaeological sites in Europe revealed that in the [[High Middle Ages]] chickens became less aggressive and began to lay eggs earlier in the breeding season.<ref name= brown>{{cite journal |last1=Brown |first1=Marley |title=Fast Food |journal=Archaeology |date=Sep–Oct 2017 |volume=70 |issue=5 |page=18 |url=https://www.archaeology.org/issues/269-1709/from-the-trenches/5820-trenches-europe-chicken-domestication |access-date=July 25, 2019 |issn=0003-8113 |archive-date=July 25, 2019 |archive-url=https://web.archive.org/web/20190725160925/https://www.archaeology.org/issues/269-1709/from-the-trenches/5820-trenches-europe-chicken-domestication |url-status=live }}</ref>
-=== Africa ===
-[[File:A Brown Hen.jpg|thumb|A chicken from a poultry in Nigeria.]]
-Chickens reached Egypt via the Middle East for purposes of [[cockfighting]] about 1400&nbsp;BC and became widely bred in Egypt around 300&nbsp;BC.<ref name="CHOF"/> Three possible routes of introduction into Africa around the early first millennium AD could have been through the Egyptian [[Nile River|Nile]] Valley, the East Africa Roman-Greek or Indian trade, or from Carthage and the Berbers, across the [[Sahara Desert|Sahara]]. The earliest known remains are from [[Mali]], [[Nubia]], East Coast, and [[South Africa]] and date back to the middle of the first millennium AD.<ref name= CHOF/>
 == Diseases ==
 {{main |Poultry disease}}
+[[File:Pesse oujheas H9N2 tanfla.JPG|thumb|left|8 day old chick with [[avian influenza]] ]]
-[[File:Pesse oujheas H9N2 tanfla.JPG|thumb|8 day old chick with [[avian influenza]] ]]
+Chickens are susceptible both to [[Parasitism|parasite]]s such as [[mite]]s, and to [[Poultry disease|diseases]] caused by [[pathogen]]s such as [[bacteria]] and [[virus]]es. The parasite ''[[Dermanyssus gallinae]]'' feeds on blood, causing irritation and reducing egg production, and acts as a vector for bacterial diseases such as [[salmonellosis]] and [[Borrelia anserina|spirochaetosis]].<ref name="Schiavone Pugliese 2022">{{Cite journal |last1=Schiavone |first1=Antonella |last2=Pugliese |first2=Nicola |last3=Otranto |first3=Domenico |last4=Samarelli |first4=Rossella |last5=Circella |first5=Elena |last6=De Virgilio |first6=Caterina |last7=Camarda |first7=Antonio |date=January 20, 2022 |title=''Dermanyssus gallinae'': the long journey of the poultry red mite to become a vector |journal=Parasites & Vectors |volume=15 |issue=1 |page=29 |doi=10.1186/s13071-021-05142-1 |pmid=35057849 |issn=1756-3305 |pmc=8772161 |doi-access=free }}</ref>
+Viral diseases include [[avian influenza]].<ref>{{cite journal |last1=Barjesteh |first1=Neda |last2=O'Dowd |first2=Kelsey |last3=Vahedi |first3=Seyed Milad |title=Antiviral responses against chicken respiratory infections: Focus on avian influenza virus and infectious bronchitis virus |journal=Cytokine |date=March 2020 |volume=127 |article-number=154961 |doi=10.1016/j.cyto.2019.154961 |pmid=31901597|pmc=7129915 }}</ref>
-Chickens are susceptible both to [[Parasitism|parasite]]s such as [[mite]]s, and to [[Poultry disease|diseases]] caused by [[pathogen]]s such as [[bacteria]] and [[virus]]es. The parasite ''[[Dermanyssus gallinae]]'' feeds on blood, causing irritation and reducing egg production, and acts as a vector for bacterial diseases such as [[salmonellosis]] and [[Borrelia anserina|spirochaetosis]].<ref name="Schiavone Pugliese 2022">{{Cite journal |last1=Schiavone |first1=Antonella |last2=Pugliese |first2=Nicola |last3=Otranto |first3=Domenico |last4=Samarelli |first4=Rossella |last5=Circella |first5=Elena |last6=De Virgilio |first6=Caterina |last7=Camarda |first7=Antonio |date=January 20, 2022 |title=''Dermanyssus gallinae'': the long journey of the poultry red mite to become a vector |journal=Parasites & Vectors |volume=15 |issue=1 |pages=29 |doi=10.1186/s13071-021-05142-1 |pmid=35057849 |issn=1756-3305 |pmc=8772161 |doi-access=free }}</ref>
-Viral diseases include [[avian influenza]].<ref>{{cite journal |last1=Barjesteh |first1=Neda |last2=O'Dowd |first2=Kelsey |last3=Vahedi |first3=Seyed Milad |title=Antiviral responses against chicken respiratory infections: Focus on avian influenza virus and infectious bronchitis virus |journal=Cytokine |date=March 2020 |volume=127 |pages=154961 |doi=10.1016/j.cyto.2019.154961 |pmid=31901597|pmc=7129915 }}</ref>
 == Use by humans ==
@@ Line 138: / Line 135: @@
 {{Main|Poultry farming}}
+{{owidslider
+|start        = 2023
+|list         = Template:OWID/chicken meat production#gallery
+|location      = commons
+|caption      =
+|title        =
+|language     =
+|file         = [[File:chicken meat production, World, 2023 (cropped).svg|link=|thumb|upright=1.6|Chicken meat production]]
+|startingView = World
+}}
-Chickens are common and widespread domestic animals, with a total population of 23.7 billion {{As of|2018|lc=y}}.<ref>{{cite web|title=Number of chickens worldwide from 1990 to 2018.|url=https://www.statista.com/statistics/263962/number-of-chickens-worldwide-since-1990/|access-date=February 23, 2020|website=Statista|archive-date=November 27, 2020|archive-url=https://web.archive.org/web/20201127124744/https://www.statista.com/statistics/263962/number-of-chickens-worldwide-since-1990/|url-status=live}}</ref> More than 50 billion chickens are reared annually as a source of meat and eggs.<ref>{{Cite web |url=https://www.ciwf.org.uk/farm-animals/chickens/ |title=About chickens |publisher=[[Compassion in World Farming]] |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20170426063521/https://www.ciwf.org.uk/farm-animals/chickens/ |archive-date=April 26, 2017 |url-status=live }}</ref> In the United States alone, more than 8 billion chickens are slaughtered each year for meat,<ref>{{Cite web |url=https://usda.library.cornell.edu/concern/publications/pg15bd88s |title=Poultry Slaughter Annual Summary |last=Fereira |first=John |website=usda.mannlib.cornell.edu |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20170426063701/http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1497 |archive-date=April 26, 2017 |url-status=live }}</ref> and more than 300 million chickens are reared for egg production.<ref>{{Cite web |url=https://usda.library.cornell.edu/concern/publications/1v53jw96n |title=Chickens and Eggs Annual Summary |last=Fereira |first=John |website=usda.mannlib.cornell.edu |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20170426061324/http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1509 |archive-date=April 26, 2017 |url-status=live }}</ref> The vast majority of poultry is raised in [[Intensive animal farming|factory farms]]. According to the [[Worldwatch Institute]], 74% of the world's poultry meat and 68% of eggs are produced this way.<ref>{{cite web |title=Towards Happier Meals In A Globalized World |url=http://www.worldwatch.org/towards-happier-meals-globalized-world |publisher=[[Worldwatch Institute]] |access-date=May 29, 2014 |archive-url=https://web.archive.org/web/20140529153518/http://www.worldwatch.org/towards-happier-meals-globalized-world |archive-date=May 29, 2014 |url-status=dead }}</ref> An alternative to intensive poultry farming is [[free-range]] farming. Friction between these two main methods has led to long-term issues of [[ethical consumerism]]. Opponents of [[intensive farming]] argue that it harms the environment, creates human health risks and is inhumane towards [[Sentience in animals|sentient animals]].<ref>{{cite journal |last1=Ilea |first1=Ramona Cristina |title=Intensive Livestock Farming: Global Trends, Increased Environmental Concerns, and Ethical Solutions |journal=Journal of Agricultural and Environmental Ethics |date=April 2009 |volume=22 |issue=2 |pages=153–167 |doi=10.1007/s10806-008-9136-3 |bibcode=2009JAEE...22..153I |s2cid=154306257 }}</ref> Advocates of intensive farming say that their efficient systems save land and food resources owing to increased productivity, and that the animals are looked after in a controlled environment.<ref>{{cite journal |last1=Tilman |first1=David |last2=Cassman |first2=Kenneth G. |last3=Matson |first3=Pamela A. |last4=Naylor |first4=Rosamond |last5=Polasky |first5=Stephen |title=Agricultural sustainability and intensive production practices |journal=Nature |date=August 2002 |volume=418 |issue=6898 |pages=671–677 |doi=10.1038/nature01014 |pmid=12167873 |bibcode=2002Natur.418..671T |s2cid=3016610 }}</ref> Chickens farmed for meat are called [[broiler]]s. Broiler breeds typically take less than six weeks to reach slaughter size,<ref>{{cite web |url=https://www.animalsaustralia.org/factsheets/broiler_chickens.php |title=Broiler Chickens Fact Sheet |website=Animals Australia |access-date=August 29, 2010 |archive-url=https://web.archive.org/web/20100712123234/http://www.animalsaustralia.org/factsheets/broiler_chickens.php |archive-date=July 12, 2010 |url-status=live }}</ref> some weeks longer for [[free range]] and [[Organic (food)|organic]] broilers.<ref>{{cite web |title=Chickens Farmed for Meat |url=https://www.ciwf.org.uk/farm-animals/chickens/meat-chickens/ |publisher=[[Compassion in World Farming]] |access-date=February 2, 2024 |archive-date=September 21, 2024 |archive-url=https://web.archive.org/web/20240921105646/https://www.ciwf.org.uk/farm-animals/chickens/meat-chickens/ |url-status=live }}</ref>
+Chickens are common and widespread domestic animals, with a total population of 23.7 billion {{As of|2018|lc=y}}.<ref>{{cite web|title=Number of chickens worldwide from 1990 to 2018.|url=https://www.statista.com/statistics/263962/number-of-chickens-worldwide-since-1990/|access-date=February 23, 2020|website=Statista|archive-date=November 27, 2020|archive-url=https://web.archive.org/web/20201127124744/https://www.statista.com/statistics/263962/number-of-chickens-worldwide-since-1990/|url-status=live}}</ref> More than 50 billion chickens are reared annually as a source of meat and eggs.<ref>{{Cite web |url=https://www.ciwf.org.uk/farm-animals/chickens/ |title=About chickens |publisher=[[Compassion in World Farming]] |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20170426063521/https://www.ciwf.org.uk/farm-animals/chickens/ |archive-date=April 26, 2017 |url-status=live }}</ref> In the United States alone, more than 8 billion chickens are slaughtered each year for meat,<ref>{{Cite web |url=https://usda.library.cornell.edu/concern/publications/pg15bd88s |title=Poultry Slaughter Annual Summary |last=Fereira |first=John |website=usda.mannlib.cornell.edu |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20170426063701/http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1497 |archive-date=April 26, 2017 |url-status=live }}</ref> and more than 300 million chickens are reared for egg production.<ref>{{Cite web |url=https://usda.library.cornell.edu/concern/publications/1v53jw96n |title=Chickens and Eggs Annual Summary |last=Fereira |first=John |website=usda.mannlib.cornell.edu |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20170426061324/http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1509 |archive-date=April 26, 2017 |url-status=live }}</ref> The vast majority of poultry is raised in [[Intensive animal farming|factory farms]]. According to the [[Worldwatch Institute]], 74% of the world's poultry meat and 68% of eggs are produced this way.<ref>{{cite web |title=Towards Happier Meals In A Globalized World |url=http://www.worldwatch.org/towards-happier-meals-globalized-world |publisher=[[Worldwatch Institute]] |access-date=May 29, 2014 |archive-url=https://web.archive.org/web/20140529153518/http://www.worldwatch.org/towards-happier-meals-globalized-world |archive-date=May 29, 2014 }}</ref> An alternative to intensive poultry farming is [[free-range]] farming. Friction between these two main methods has led to long-term issues of [[ethical consumerism]]. Opponents of [[intensive farming]] argue that it harms the environment, creates human health risks and is inhumane towards [[Sentience in animals|sentient animals]].<ref>{{cite journal |last1=Ilea |first1=Ramona Cristina |title=Intensive Livestock Farming: Global Trends, Increased Environmental Concerns, and Ethical Solutions |journal=Journal of Agricultural and Environmental Ethics |date=April 2009 |volume=22 |issue=2 |pages=153–167 |doi=10.1007/s10806-008-9136-3 |bibcode=2009JAEE...22..153I |s2cid=154306257 }}</ref> Advocates of intensive farming say that their efficient systems save land and food resources owing to increased productivity, and that the animals are looked after in a controlled environment.<ref>{{cite journal |last1=Tilman |first1=David |last2=Cassman |first2=Kenneth G. |last3=Matson |first3=Pamela A. |last4=Naylor |first4=Rosamond |last5=Polasky |first5=Stephen |title=Agricultural sustainability and intensive production practices |journal=Nature |date=August 2002 |volume=418 |issue=6898 |pages=671–677 |doi=10.1038/nature01014 |pmid=12167873 |bibcode=2002Natur.418..671T |s2cid=3016610 }}</ref> Chickens farmed for meat are called [[broiler]]s. Broiler breeds typically take less than six weeks to reach slaughter size,<ref>{{cite web |url=https://www.animalsaustralia.org/factsheets/broiler_chickens.php |title=Broiler Chickens Fact Sheet |website=Animals Australia |access-date=August 29, 2010 |archive-url=https://web.archive.org/web/20100712123234/http://www.animalsaustralia.org/factsheets/broiler_chickens.php |archive-date=July 12, 2010 |url-status=live }}</ref> some weeks longer for [[free range]] and [[Organic (food)|organic]] broilers.<ref>{{cite web |title=Chickens Farmed for Meat |url=https://www.ciwf.org.uk/farm-animals/chickens/meat-chickens/ |publisher=[[Compassion in World Farming]] |access-date=February 2, 2024 |archive-date=September 21, 2024 |archive-url=https://web.archive.org/web/20240921105646/https://www.ciwf.org.uk/farm-animals/chickens/meat-chickens/ |url-status=live }}</ref>
-[[File:Florida chicken house.jpg|thumb|A commercial chicken house with open sides raising broiler pullets for meat]]
+Chickens farmed primarily for eggs are called layer hens. The UK alone consumes more than 34 million eggs per day.<ref>{{Cite web |url=https://www.egginfo.co.uk/egg-facts-and-figures/industry-information/data |title=UK Egg Industry Data |website=Official Egg Info |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20161230000509/https://www.egginfo.co.uk/egg-facts-and-figures/industry-information/data |archive-date=December 30, 2016 |url-status=live }}</ref> Hens of some breeds can produce over 300 eggs per year; the highest authenticated rate of egg laying is 371 eggs in 364 days.<ref>{{cite book |last1=Glenday |first1=Craig |title=Guinness World Records 2011 |date=April 26, 2011 |publisher=[[Jim Pattison Group]] |isbn=978-0-440-42310-2 |page=286}}</ref> After 12 months of laying, the commercial hen's egg-laying ability declines to the point where the flock is commercially unviable. Hens, particularly from [[battery cage]] systems, are sometimes infirm or have lost a significant amount of their feathers, and their life expectancy has been reduced from around seven years to less than two years.<ref name="Browne">{{cite news |url=https://www.theguardian.com/lifeandstyle/2002/mar/10/foodanddrink.features1 |work=The Guardian |location=London |title=Ten weeks to live |first=Anthony |last=Browne |date=March 10, 2002 |access-date=April 28, 2010 |archive-url=https://web.archive.org/web/20080516080228/http://observer.guardian.co.uk/foodmonthly/story/0,,662799,00.html |archive-date=May 16, 2008 |url-status=live }}</ref> In the UK and Europe, laying hens are then slaughtered and used in processed foods, or sold as 'soup hens'.<ref name="Browne" /> In some other countries, flocks are sometimes [[Forced molting|force moulted]] rather than being slaughtered to re-invigorate egg-laying. This involves complete withdrawal of food (and sometimes water) for 7–14 days<ref name="Patwardhan and King, (2011)">{{cite journal |last1=Patwardhan |first1=D. |last2=King |first2=A. |year=2011 |title=Review: feed withdrawal and non feed withdrawal moult |journal=World's Poultry Science Journal |volume=67 |issue=2 |pages=253–268 |doi=10.1017/s0043933911000286|s2cid=88353703 }}</ref> or sufficiently long to cause a body weight loss of 25 to 35%,<ref name="Webster, (2003)">{{cite journal |last1=Webster |first1=A.B. |year=2003 |title=Physiology and behavior of the hen during induced moult |journal=Poultry Science |volume=82 |issue=6 |pages=992–1002 |doi=10.1093/ps/82.6.992 |pmid=12817455|doi-access=free }}</ref> or up to 28 days under experimental conditions.<ref name="Molino et al., (2009)">{{cite journal |last1=Molino |first1=A.B. |last2=Garcia |first2=E.A. |last3=Berto |first3=D.A. |last4=Pelícia |first4=K. |last5=Silva |first5=A.P. |last6=Vercese |first6=F. |year=2009 |title=The Effects of Alternative Forced-Molting Methods on The Performance and Egg Quality of Commercial Layers |journal=Brazilian Journal of Poultry Science |volume=11 |issue=2 |pages=109–113 |doi=10.1590/s1516-635x2009000200006|doi-access=free |hdl=11449/14340 |hdl-access=free }}</ref> This stimulates the hen to lose her feathers but also re-invigorates egg-production. Some flocks may be force-moulted several times. In 2003, more than 75% of all flocks were moulted in the US.<ref name="Yousaf and Chaudhry, (2008)">{{cite journal |last1=Yousaf |first1=M. |last2=Chaudhry |first2=A.S. |title=History, changing scenarios and future strategies to induce moulting in laying hens |journal=World's Poultry Science Journal |date=March 1, 2008 |volume=64 |issue=1 |pages=65–75 |doi=10.1017/s0043933907001729 |s2cid=34761543 |url=http://eprint.ncl.ac.uk/file_store/production/56559/452E6892-26EF-40C6-891B-048E9FE17D2E.pdf |access-date=October 23, 2020 |archive-date=November 24, 2020 |archive-url=https://web.archive.org/web/20201124090812/https://eprint.ncl.ac.uk/file_store/production/56559/452E6892-26EF-40C6-891B-048E9FE17D2E.pdf |url-status=live }}</ref> Chickens are one of the most efficient sources of foods for many different purposes.
-Chickens farmed primarily for eggs are called layer hens. The UK alone consumes more than 34 million eggs per day.<ref>{{Cite web |url=https://www.egginfo.co.uk/egg-facts-and-figures/industry-information/data |title=UK Egg Industry Data |website=Official Egg Info |access-date=April 25, 2017 |archive-url=https://web.archive.org/web/20161230000509/https://www.egginfo.co.uk/egg-facts-and-figures/industry-information/data |archive-date=December 30, 2016 |url-status=live }}</ref> Hens of some breeds can produce over 300 eggs per year; the highest authenticated rate of egg laying is 371 eggs in 364 days.<ref>{{cite book |last1=Glenday |first1=Craig |title=Guinness World Records 2011 |date=April 26, 2011 |publisher=[[Jim Pattison Group]] |isbn=978-0440423102 |page=286}}</ref> After 12 months of laying, the commercial hen's egg-laying ability declines to the point where the flock is commercially unviable. Hens, particularly from [[battery cage]] systems, are sometimes infirm or have lost a significant amount of their feathers, and their life expectancy has been reduced from around seven years to less than two years.<ref name="Browne">{{cite news |url=https://www.theguardian.com/lifeandstyle/2002/mar/10/foodanddrink.features1 |work=The Guardian |location=London |title=Ten weeks to live |first=Anthony |last=Browne |date=March 10, 2002 |access-date=April 28, 2010 |archive-url=https://web.archive.org/web/20080516080228/http://observer.guardian.co.uk/foodmonthly/story/0,,662799,00.html |archive-date=May 16, 2008 |url-status=live }}</ref> In the UK and Europe, laying hens are then slaughtered and used in processed foods, or sold as 'soup hens'.<ref name="Browne" /> In some other countries, flocks are sometimes [[Forced molting|force moulted]] rather than being slaughtered to re-invigorate egg-laying. This involves complete withdrawal of food (and sometimes water) for 7–14 days<ref name="Patwardhan and King, (2011)">{{cite journal |last1=Patwardhan |first1=D. |last2=King |first2=A. |year=2011 |title=Review: feed withdrawal and non feed withdrawal moult |journal=World's Poultry Science Journal |volume=67 |issue=2 |pages=253–268 |doi=10.1017/s0043933911000286|s2cid=88353703 }}</ref> or sufficiently long to cause a body weight loss of 25 to 35%,<ref name="Webster, (2003)">{{cite journal |last1=Webster |first1=A.B. |year=2003 |title=Physiology and behavior of the hen during induced moult |journal=Poultry Science |volume=82 |issue=6 |pages=992–1002 |doi=10.1093/ps/82.6.992 |pmid=12817455|doi-access=free }}</ref> or up to 28 days under experimental conditions.<ref name="Molino et al., (2009)">{{cite journal |last1=Molino |first1=A.B. |last2=Garcia |first2=E.A. |last3=Berto |first3=D.A. |last4=Pelícia |first4=K. |last5=Silva |first5=A.P. |last6=Vercese |first6=F. |year=2009 |title=The Effects of Alternative Forced-Molting Methods on The Performance and Egg Quality of Commercial Layers |journal=Brazilian Journal of Poultry Science |volume=11 |issue=2 |pages=109–113 |doi=10.1590/s1516-635x2009000200006|doi-access=free |hdl=11449/14340 |hdl-access=free }}</ref> This stimulates the hen to lose her feathers but also re-invigorates egg-production. Some flocks may be force-moulted several times. In 2003, more than 75% of all flocks were moulted in the US.<ref name="Yousaf and Chaudhry, (2008)">{{cite journal |last1=Yousaf |first1=M. |last2=Chaudhry |first2=A.S. |title=History, changing scenarios and future strategies to induce moulting in laying hens |journal=World's Poultry Science Journal |date=March 1, 2008 |volume=64 |issue=1 |pages=65–75 |doi=10.1017/s0043933907001729 |s2cid=34761543 |url=http://eprint.ncl.ac.uk/file_store/production/56559/452E6892-26EF-40C6-891B-048E9FE17D2E.pdf |access-date=October 23, 2020 |archive-date=November 24, 2020 |archive-url=https://web.archive.org/web/20201124090812/https://eprint.ncl.ac.uk/file_store/production/56559/452E6892-26EF-40C6-891B-048E9FE17D2E.pdf |url-status=live }}</ref> Chickens are one of the most efficient sources of foods for many different purposes.
+<gallery class=center mode=nolines widths=200 heights=180>
+File:Wright, Stephenson & Co Ltd - Woman feeding chickens (52532).jpg|Woman feeding chickens by hand, c.1930
+File:Florida chicken house.jpg|A commercial chicken house with open sides raising broiler pullets for meat
+File:A 95 year old woman with her pet rooster, Havana, Cuba.jpg|Woman with her pet rooster, Cuba
+</gallery>
 === As pets ===
-{{seealso|Urban chicken keeping}}
+{{further|Urban chicken keeping}}
 Keeping chickens as pets became increasingly popular in the 2000s<ref>{{cite news |title=Some homeowners find chickens all the rage |work=[[Chicago Tribune]] |date=July 27, 2007 |last=Fly |first=Colin |url=https://pqasb.pqarchiver.com/chicagotribune/access/1310840201.html?.dids=1310840201:1310840201&FMT=ABS&FMTS=ABS:FT&type=current&date=Jul+27,+2007&author=Colin+Fly&pub=Chicago+Tribune&desc=Some+homeowners+find+chickens+all+the+rage&pqatl=google }}{{dead link|date=July 2024|bot=medic}}{{cbignore|bot=medic}}</ref> among urban and suburban residents.<ref>{{cite news |title=Cooped up in suburbia |work=[[Boston Globe]] |date=December 16, 2004 |last=Pollack-Fusi |first=Mindy |url=https://www.boston.com/yourlife/home/articles/2004/12/16/cooped_up_in_suburbia/ |access-date=June 4, 2020 |archive-date=March 4, 2016 |archive-url=https://web.archive.org/web/20160304063550/http://www.boston.com/yourlife/home/articles/2004/12/16/cooped_up_in_suburbia/ |url-status=live }}</ref> Many people obtain chickens for their egg production but often name them and treat them as any other pet like cats or dogs. Chickens provide companionship and have individual personalities. While many do not cuddle much, they will eat from one's hand, jump onto one's lap, respond to and follow their handlers, as well as show affection.<ref>{{Cite news|url=https://www.nytimes.com/2020/11/25/magazine/backyard-chickens-empathy.html |archive-url=https://web.archive.org/web/20201125101336/https://www.nytimes.com/2020/11/25/magazine/backyard-chickens-empathy.html |archive-date=November 25, 2020 |url-access=subscription |url-status=live|title = How Caring for Backyard Chickens Stretched My Emotional Muscles|newspaper = The New York Times|date = November 25, 2020|last1 = Kreilkamp|first1 = Ivan}}</ref><ref>{{Cite web|url=https://www.latimes.com/style/pets/la-hm-pets-chickens-20170827-story.html|title=Chickens will become a beloved pet — just like the family dog|last=Boone|first=Lisa|website=[[Los Angeles Times]]|date=August 27, 2017|access-date=April 3, 2019|archive-date=April 2, 2019|archive-url=https://web.archive.org/web/20190402104824/https://www.latimes.com/style/pets/la-hm-pets-chickens-20170827-story.html|url-status=live}}</ref> Chickens are social, inquisitive, intelligent<ref>{{Cite web|last=Barras|first=Colin|title=Despite what you might think, chickens are not stupid|url=https://www.bbc.com/earth/story/20170110-despite-what-you-might-think-chickens-are-not-stupid|archive-url=https://web.archive.org/web/20210605084929/https://www.bbc.com/earth/story/20170110-despite-what-you-might-think-chickens-are-not-stupid|archive-date=June 5, 2021|access-date=September 6, 2020|website=www.bbc.com|language=en}}</ref> birds, and many people find their behaviour entertaining.<ref name='UPC good homes' >{{cite web |url=https://www.upc-online.org/home.html |title=Providing a Good Home for Chickens |author=United Poultry Concerns |access-date=May 4, 2009 |archive-url=https://web.archive.org/web/20090605061816/http://www.upc-online.org/home.html |archive-date=June 5, 2009 |url-status=live }}</ref> Certain breeds, such as [[silkie]]s and many [[Bantam (poultry)|bantam]] varieties, are generally docile and are often recommended as good pets around children with disabilities.<ref>{{cite web |url=https://www.henkeeping.co.uk/henkeeping/choosing-your-chickens/ |website=Clucks and Chooks |title=Choosing Your Chickens |url-status=live |archive-url=https://web.archive.org/web/20090730222405/http://www.henkeeping.co.uk/which.html |archive-date=July 30, 2009}}</ref>
@@ Line 155: / Line 168: @@
 [[File:COCK FIGHT.JPG|thumb|A [[cockfight]] in [[Tamil Nadu]], India, 2011 ]]
-A [[cockfight]] is a contest held in a ring called a cockpit between two cocks. Cockfighting is outlawed in many countries as involving [[cruelty to animals]].<ref>{{cite news|author=Raymond Hernandez |url=https://www.nytimes.com/1995/04/11/nyregion/blood-sport-gets-blood-fans-cockfighting-don-t-understand-its-outlaw-status.html?pagewanted=all&src=pm |title=A Blood Sport Gets in the Blood; Fans of Cockfighting Don't Understand Its Outlaw Status |work=The New York Times |location=New York City Metropolitan Area |date=April 11, 1995 |access-date=May 10, 2014}}</ref> The activity seems to have been practised in the [[Indus Valley civilisation]] from 2500 to 2100 BC.<ref name="Crawford 1990">{{cite book |last=Crawford |first=R. D. |title=''Poultry Breeding and Genetics'' |publisher=[[Elsevier]] |year=1990 |pages=10–11 |isbn=978-0444885579 |ol=2207173M |url=https://openlibrary.org/books/OL2207173M/Poultry_breeding_and_genetics |access-date=February 2, 2024 |archive-date=April 18, 2023 |archive-url=https://web.archive.org/web/20230418123608/https://openlibrary.org/books/OL2207173M/Poultry_breeding_and_genetics |url-status=live }}</ref> In the process of domestication, chickens were apparently kept initially for cockfighting, and only later used for food.<ref name="Lawler Adler 2012">{{cite journal |last1=Lawler |first1=Andrew |last2=Adler |first2=Jerry |title=How the Chicken Conquered the World |journal=Smithsonian Magazine |issue=June 2012 |date=June 2012 |url=http://www.smithsonianmag.com/history/how-the-chicken-conquered-the-world-87583657/ |access-date=February 2, 2024 |archive-date=October 31, 2019 |archive-url=https://web.archive.org/web/20191031040210/https://www.smithsonianmag.com/history/how-the-chicken-conquered-the-world-87583657/ |url-status=live }}</ref>
+A [[cockfight]] is a contest held in a ring called a cockpit between two cocks. Cockfighting is outlawed in many countries as involving [[cruelty to animals]].<ref>{{cite news|author=Raymond Hernandez |url=https://www.nytimes.com/1995/04/11/nyregion/blood-sport-gets-blood-fans-cockfighting-don-t-understand-its-outlaw-status.html?pagewanted=all&src=pm |title=A Blood Sport Gets in the Blood; Fans of Cockfighting Don't Understand Its Outlaw Status |work=The New York Times |location=New York City Metropolitan Area |date=April 11, 1995 |access-date=May 10, 2014}}</ref> The activity seems to have been practised in the [[Indus Valley civilisation]] from 2500 to 2100 BC.<ref name="Crawford 1990">{{cite book |last=Crawford |first=R. D. |title=''Poultry Breeding and Genetics'' |publisher=[[Elsevier]] |year=1990 |pages=10–11 |isbn=978-0-444-88557-9 |ol=2207173M }}</ref> In the process of domestication, chickens were apparently kept initially for cockfighting, and only later used for food.<ref name="Lawler Adler 2012">{{cite journal |last1=Lawler |first1=Andrew |last2=Adler |first2=Jerry |title=How the Chicken Conquered the World |journal=Smithsonian Magazine |issue=June 2012 |date=June 2012 |url=http://www.smithsonianmag.com/history/how-the-chicken-conquered-the-world-87583657/ |access-date=February 2, 2024 |archive-date=October 31, 2019 |archive-url=https://web.archive.org/web/20191031040210/https://www.smithsonianmag.com/history/how-the-chicken-conquered-the-world-87583657/ |url-status=live }}</ref>
-=== In science===
+===In science===
 Chickens have long been used as [[model organism]]s to study developing embryos. Large numbers of embryos can be provided commercially; fertilized eggs can easily be opened and used to observe the developing embryo. Equally important, embryologists can carry out experiments on such embryos, close the egg again and study the effects later in development. For instance, many important discoveries in [[limb development]] have been made using chicken embryos, such as the discovery of the [[apical ectodermal ridge]] and the [[zone of polarizing activity]].<ref>{{cite journal |last1=Young |first1=John J. |last2=Tabin |first2=Clifford J. |title=Saunders's framework for understanding limb development as a platform for investigating limb evolution |journal=Developmental Biology |date=September 2017 |volume=429 |issue=2 |pages=401–408 |doi=10.1016/j.ydbio.2016.11.005 |pmid=27840200 |pmc=5426996 }}</ref>
@@ Line 164: / Line 177: @@
 === In culture, folklore, and religion ===
 {{Anchor|Crowing|Cockadoodledoo|Cocka-doodle-doo}}
 {{main|Cultural references to chickens}}
 Chickens are featured widely in [[folklore]], [[religion]], [[literature]], and popular culture. The chicken is a sacred animal in many cultures and deeply embedded in belief systems and religious practices.<ref name="smithsonianmag.com">{{cite magazine |last1=Adler |first1=Jerry |last2=Lawler |first2=Andrew |date=June 2012 |title=How the Chicken Conquered the World |url=https://www.smithsonianmag.com/history/how-the-chicken-conquered-the-world-87583657/ |magazine=Smithsonian |access-date=May 24, 2012 |archive-url=https://web.archive.org/web/20121103193648/http://www.smithsonianmag.com/history-archaeology/How-the-Chicken-Conquered-the-World.html |archive-date=November 3, 2012 |url-status=live}}</ref>
-Roosters are sometimes used for [[divination]], a practice called alectryomancy. This involves the sacrifice of a sacred rooster, often during a ritual [[cockfight]], used as a form of communication with the gods.<ref>{{cite book |url=https://books.google.com/books?id=vvVPAAAAMAAJ&q=Alectryomancy+cockfight&pg=PA394 |title=Encyclopædia Perthensis; Or Universal Dictionary of the Arts, Sciences, Literature, &c. Intended to Supersede the Use of Other Books of Reference |publisher=John Brown |year=1816 |edition=2nd |volume=1 |page=394 |access-date=February 2, 2024 |archive-date=September 21, 2024 |archive-url=https://web.archive.org/web/20240921105802/https://books.google.com/books?id=vvVPAAAAMAAJ&q=Alectryomancy+cockfight&pg=PA394#v=snippet&q=Alectryomancy%20cockfight&f=false |url-status=live }}</ref> In [[Gabriel García Márquez]]'s Nobel-Prize-winning 1967 novel ''[[One Hundred Years of Solitude]]'', cockfighting is outlawed in the town of Macondo after the patriarch of the Buendia family murders his cockfighting rival and is haunted by the man's ghost.<ref>{{cite news |title=Love and Immolation in Argentina |url=https://www.washingtonpost.com/archive/entertainment/books/1981/08/16/love-and-immolation-in-argentina/9cf0bdac-cfc3-4198-8824-d89d5e059c55/ |newspaper=[[Washington Post]] |date=August 16, 1981 |access-date=February 2, 2024 |archive-date=August 27, 2017 |archive-url=https://web.archive.org/web/20170827142619/https://www.washingtonpost.com/archive/entertainment/books/1981/08/16/love-and-immolation-in-argentina/9cf0bdac-cfc3-4198-8824-d89d5e059c55/ |url-status=live }}</ref> [[Chicken joke]]s have been made at least since ''[[The Knickerbocker]]'' published one in 1847.<ref>''The Knickerbocker, or The New York Monthly'', March 1847, p. 283.</ref> Chickens have been featured in art in farmyard scenes such as [[Adriaen van Utrecht]]'s 1646 ''Turkeys and Chickens'' and [[Walter Osborne]]'s 1885 ''Feeding the Chickens''.<ref>{{cite web |last1=Kellogg |first1=Diane M. |title=Chickens in Art History |url=https://www.paintingworldmag.com/post/chickens-in-art-history |publisher=Painting World Magazine |access-date=February 2, 2024 |date=May 22, 2020 |archive-date=February 2, 2024 |archive-url=https://web.archive.org/web/20240202161615/https://www.paintingworldmag.com/post/chickens-in-art-history |url-status=dead }}</ref> The [[nursery rhyme]] "[[Cock a doodle doo]]", its chorus line imitating the cockerel's call, was published in ''[[Mother Goose's Melody]]'' in 1765.<ref>{{cite book |last1=Opie |first1=Iona |last2=Opie |first2=Peter |title=The Oxford Dictionary of Nursery Rhymes |publisher=[[Oxford University Press]] |orig-year=1951 |edition=2nd |year=1997 |page=128}}</ref>
+Roosters are sometimes used for [[divination]], a practice called [[alectryomancy]]. This involves the sacrifice of a sacred rooster, often during a ritual [[cockfight]], used as a form of communication with the gods.<ref>{{cite book |url=https://books.google.com/books?id=vvVPAAAAMAAJ&q=Alectryomancy+cockfight&pg=PA394 |title=Encyclopædia Perthensis; Or Universal Dictionary of the Arts, Sciences, Literature, &c. Intended to Supersede the Use of Other Books of Reference |publisher=John Brown |year=1816 |edition=2nd |volume=1 |page=394 |access-date=February 2, 2024 |archive-date=September 21, 2024 |archive-url=https://web.archive.org/web/20240921105802/https://books.google.com/books?id=vvVPAAAAMAAJ&q=Alectryomancy+cockfight&pg=PA394#v=snippet&q=Alectryomancy%20cockfight&f=false |url-status=live }}</ref> In [[Gabriel García Márquez]]'s Nobel-Prize-winning 1967 novel ''[[One Hundred Years of Solitude]]'', cockfighting is outlawed in the town of Macondo after the patriarch of the Buendia family murders his cockfighting rival and is haunted by the man's ghost.<ref>{{cite news |title=Love and Immolation in Argentina |url=https://www.washingtonpost.com/archive/entertainment/books/1981/08/16/love-and-immolation-in-argentina/9cf0bdac-cfc3-4198-8824-d89d5e059c55/ |newspaper=[[Washington Post]] |date=August 16, 1981 |access-date=February 2, 2024 |archive-date=August 27, 2017 |archive-url=https://web.archive.org/web/20170827142619/https://www.washingtonpost.com/archive/entertainment/books/1981/08/16/love-and-immolation-in-argentina/9cf0bdac-cfc3-4198-8824-d89d5e059c55/ |url-status=live }}</ref> The pseudo-riddle "[[Why did the chicken cross the road?]]" dates to 1847, or earlier.<ref>{{cite magazine |title=Editor's Table |magazine=The Knickerbocker, or The New York Monthly |date=March 1847 |page=283 |url=https://babel.hathitrust.org/cgi/pt?id=mdp.39015030022381&seq=485 |quote=There are 'quips and quillets' which ''seem'' actual conundrums, but yet are none. Of such is this: 'Why does a chicken cross the street? [...] Because it wants to get on the other side!'}}</ref> Chickens have been featured in art in farmyard scenes such as [[Adriaen van Utrecht]]'s 1646 ''Turkeys and Chickens'' and [[Walter Osborne]]'s 1885 ''Feeding the Chickens''.<ref>{{cite web |last1=Kellogg |first1=Diane M. |title=Chickens in Art History |url=https://www.paintingworldmag.com/post/chickens-in-art-history |publisher=Painting World Magazine |access-date=February 2, 2024 |date=May 22, 2020 |archive-date=February 2, 2024 |archive-url=https://web.archive.org/web/20240202161615/https://www.paintingworldmag.com/post/chickens-in-art-history }}</ref> The [[nursery rhyme]] "[[Cock a doodle doo]]", its chorus line imitating the cockerel's call, was published in ''[[Mother Goose's Melody]]'' in 1765.<ref>{{cite book |last1=Opie |first1=Iona |last2=Opie |first2=Peter |title=The Oxford Dictionary of Nursery Rhymes |publisher=[[Oxford University Press]] |orig-date=1951 |edition=2nd |year=1997 |page=128}}</ref>
 The 2000 animated [[adventure film|adventure]] [[comedy film]] ''[[Chicken Run]]'', directed by [[Peter Lord]] and [[Nick Park]], featured [[Anthropomorphism|anthropomorphic]] chickens with many chicken jokes.<ref>{{cite magazine |last=Corliss |first=Richard |date=December 4, 2000 |title=Run, Chicken Run! |language=en-US |magazine=Time |url=https://content.time.com/time/world/article/0,8599,2047283,00.html |access-date=March 23, 2023 |issn=0040-781X |archive-date=January 24, 2023 |archive-url=https://web.archive.org/web/20230124033415/https://content.time.com/time/world/article/0,8599,2047283,00.html |url-status=live }}</ref><ref>{{Cite web|url=https://catalog.afi.com/Catalog/moviedetails/61096|title=AFI&#124;Catalog|access-date=August 17, 2018|archive-date=August 17, 2018|archive-url=https://web.archive.org/web/20180817060102/https://catalog.afi.com/Catalog/moviedetails/61096|url-status=live}}</ref><ref>{{Cite web |url=https://www.sfgate.com/movies/amp/Chicken-Recipe-Simply-Divine-Action-comedy-3239861.php|title='Chicken' Recipe Simply Divine / Action comedy blends great story, animation |website=SFGate |date=June 21, 2000 |access-date=June 2, 2021 |archive-date=June 2, 2021 |archive-url=https://web.archive.org/web/20210602214504/https://www.sfgate.com/movies/amp/Chicken-Recipe-Simply-Divine-Action-comedy-3239861.php |url-status=live}}</ref>
@@ Line 206: / Line 216: @@
 [[Category:Birds described in 1758]]
 [[Category:Bird common names]]
-[[Category:Taxa named by Carl Linnaeus]]
+[[Category:Animal taxa named by Carl Linnaeus]]
 [[Category:Articles containing video clips]]
 [[Category:Junglefowls]]

Chicken: Difference between revisions

Latest revision as of 09:14, 20 November 2025

Contents

Nomenclature

Description

Reproduction and life-cycle

Origin

Phylogeny

Domestication

Dispersal

Austronesia

Africa

Americas

Eurasia

Diseases

Use by humans

Farming

As pets

Cockfighting

In science

In culture, folklore, and religion

Notes

References

External links

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Chicken: Difference between revisions

Latest revision as of 09:14, 20 November 2025

Nomenclature

Description

Reproduction and life-cycle

Origin

Phylogeny

Domestication

Dispersal

Austronesia

Africa

Americas

Eurasia

Diseases

Use by humans

Farming

As pets

Cockfighting

In science

In culture, folklore, and religion

Notes

References

External links

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