CHICKEN English meaning

Genomic studies estimated that the chicken was domesticated 8,000 years ago in Southeast Asia and spread to China and India 2,000 to 3,000 years later. 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. The concept of dominance, involving pecking, was described in female chickens by Thorleif Schjelderup-Ebbe in 1921 as the «pecking order». Individual chickens dominate others, establishing a pecking order; dominant individuals take priority for access to food and nest sites.

Analysis of the most popular commercial breed shows that the White Leghorn breed possesses a mosaic of divergent ancestries inherited from different subspecies of red junglefowl. Archaeological evidence appeared to support domestic chickens in Southeast Asia well before 6000 BC, China by 6000 BC and India by 2000 BC. Exactly when and where the chicken was domesticated was controversial. Inbreeding of White Leghorn chickens tends to cause inbreeding depression expressed as reduced egg number and delayed sexual maturity. When eggs are placed in a hypoxic environment, chicken embryos from these populations express much E2BET more hemoglobin than embryos from other chicken populations.

Domestication

Fertilized embryos develop quickly, and chicks hatch approximately 21 days later. There is some debate about what the chicken’s scientific name should be. 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. The pseudo-riddle «Why did the chicken cross the road?» dates to 1847, or earlier.

• Mating typically involves a sequence in which the male approaches the female and performs a waltzing display.
• During the Hellenistic period (4th–2nd centuries BC), in the southern Levant, chickens began to be widely domesticated for food.
• The first pictures of chickens in Europe are found on Corinthian pottery of the 7th century BC.
• Chicks are born covered in down, but they mature quickly, becoming fully feathered after four to five weeks.
• The dance triggers a response in the hen and when she responds to his call, the rooster may mount the hen and proceed with the mating.

Chickens are capable of mobbing and killing a weak or inexperienced predator, such as a young fox. Some breeds have a mutation that causes extra feathering under the face, giving the appearance of a beard. Modern varieties however grow much faster; by day 35 a Ross 708 broiler may weigh 1.8 kg (4.0 lb) as against the 1.05 kg (2.3 lb) of a heritage chicken of the same age. Newly hatched chicks of both modern and heritage varieties weigh the same, about 37 g (1.3 oz). While the origin is Germanic, it is unclear exactly where the word came from, although it could ultimately have come from an imitation of the sound a chicken makes. The word chicken comes from Old English cicen (pronounced essentially the same as in Modern English).

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. Large numbers of embryos can be provided commercially; fertilized eggs can easily be opened and used to observe the developing embryo. Keeping chickens as pets became increasingly popular in the 2000s among urban and suburban residents.

Chickens have been thought of primarily as providers of food, but their cognition, emotions, and sociality are comparable with other birds and mammals. Chickens are gregarious, living in flocks, and incubate eggs and raise young communally. The body is round, the legs are unfeathered in most breeds, and the wings are short. Chicken can mean a chick, and this was historically the meaning of the word chicken, as in William Shakespeare’s play Macbeth, where Macduff laments the death of «all my pretty chickens and their dam». As of 2023, the global chicken population exceeds 26.5 billion, with more than 50 billion birds produced annually for consumption. It was first domesticated around 8,000 years ago and is one of the most common and widespread domesticated animals in the world.

Africa

The market for chicken meat has grown dramatically since then, with worldwide exports reaching nearly 12.5 million metric tons (about 13.8 million tons) by the early 21st century. By the mid-20th century, however, meat production had outstripped egg production as a specialized industry. For most of that period, chickens were a common part of the livestock complement of farms and ranches throughout Eurasia and Africa. Chicken domestication likely occurred more than once in Southeast Asia and possibly India over the most recent 7,400 years, and the first domestications may have been for religious reasons or for the raising of fighting birds. Each flock of chickens develops a social hierarchy that determines access to food, nesting sites, mates, and other resources. At about six months, males produce viable sperm, and females produce viable eggs.

Skeletons of birds in the Gallus genus were used as grave goods at the site, confirming domestication. The chicks imprint on the hen and subsequently follow her continually. 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. Hens often try to lay in nests that already contain eggs and sometimes move eggs from neighbouring nests into their own. As with all birds, reproduction is controlled by a neuroendocrine system, the Gonadotropin-Releasing Hormone-I neurons in the hypothalamus. Sperm transfer occurs by cloacal contact between the male and female, in an action called the ‘cloacal kiss’.

The first pictures of chickens in Europe are found on Corinthian pottery of the 7th century BC. Phoenicians spread chickens along the Mediterranean coasts as far as Iberia. These chickens may have been introduced during pre-Columbian times to South America via Polynesian seafarers, but this is disputed.

Females (mature hens and younger chickens, called pullets) are raised for meat and for their edible eggs. 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. The chicken (Gallus gallus domesticus) is a domesticated form of the red junglefowl (Gallus gallus), originally native to Southeast Asia. The chicken is perhaps the most widely domesticated fowl, raised worldwide for its meat and eggs.