The Chicken
The chicken (Gallus gallus domesticus) is a large and round short-winged bird, domesticated from the red junglefowl of Southeast Asia around 8,000 years ago. Most chickens are raised for food, providing meat and eggs; others are kept as pets or for cockfighting. Chickens are common and widespread domestic animals, with a total population of 23.7 billion as of 2018, and an annual production of more than 50 billion birds. A hen bred for laying can produce over 300 eggs per year. There are numerous cultural references to chickens in folklore, religion, and literature..
Description
Chickens are relatively large birds, active by day. The body is round, the legs are unfeathered, and the wings are short.[17] Wild junglefowl can fly; chickens and their flight muscles are too heavy to allow them to fly more than a short distance.[18] Size and coloration vary widely between breeds.[17] 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.[19]
Origin
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.[40] Chickens are descended primarily from the red junglefowl (Gallus gallus) and are scientifically classified as the same species.[41] Domesticated chickens freely interbreed with populations of red junglefowl.[41] The domestic chicken has subsequently hybridised with grey junglefowl, Sri Lankan junglefowl and green junglefowl;[42] a gene for yellow skin, for instance, was incorporated into domestic birds from the grey junglefowl (G. sonneratii).[43] It is estimated that chickens share between 71 and 79% of their genome with red junglefowl.[42]
Terms for chicken
There are ten terms of chicken:
- Biddy: a chicken, or a newly hatched chicken
- Capon: a castrated or neutered male chicken
- Chick: a young chicken
- Chook /tʃʊk/: a chicken (Australia/New Zealand, informal)
- Cock: a fertile adult male chicken
- Cockerel: a young male chicken less than a year old
- Hen: an adult female chicken
- Pullet: a young female chicken less than a year old. In the poultry industry, a pullet is a sexually immature chicken less than 22 weeks of age
- Rooster: a fertile adult male chicken, especially in North America. Originated in the 18th century as a euphemism to avoid the sexual connotation of the British English cock
- Yardbird: a chicken (southern United States, dialectal)