Chicken Wikipedia

Chickens are primarily kept for their meat and eggs, though they are also kept as pets. In situations where one adult bird challenges another—which happens most often when a new bird is introduced into the flock—fights involving males risk injury and death more often than fights involving females. In groups of male chicks, however, fights for dominance may continue into adulthood. The pecking order is established within groups of female chicks by the 10th week of life. The time between ovulation and egg-laying is approximately 23–26 hours.

Social hierarchy

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. This involves the sacrifice of a sacred rooster, often during a ritual cockfight, used as a form of communication with the gods.

• 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.
• These domesticated chickens spread across Southeast and South Asia where they interbred with local wild species of junglefowl, forming genetically and geographically distinct groups.
• Despite the chicken’s close relationship with the red jungle fowl, there is evidence that the gray jungle fowl (G. sonneratii) of southern India and other jungle fowl species, also members of Gallus, may have contributed to the bird’s ancestry.
• The time between ovulation and egg-laying is approximately 23–26 hours.
• Keeping chickens as pets became increasingly popular in the 2000s among urban and suburban residents.

Coconut Chicken Curry – quick and easy

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 more hemoglobin than embryos from other chicken populations. Under natural conditions, most birds lay only until a clutch is complete; they then incubate all the eggs. Adult chickens of both sexes have a fleshy crest on their heads called eaub.info/bd 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.

Sperm transfer occurs by cloacal contact between the male and female, in an action called the ‘cloacal kiss’. 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”.

In older sources, and still often in trade and scientific contexts, chickens as a species are described as common fowl or domestic fowl. Many immature males (cockerels) are castrated (usually chemically, with hormones that cause atrophying of the testicles) to become meat birds (capons). 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.