Chicken Wikipedia
Fertile chicken eggs hatch at the end of the khelaghor bd 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.
- A flock usually includes one dominant adult male, a few subdominant males, and two or more females that are carefully watched over by the dominant male.
- 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.
- These chickens may have been introduced during pre-Columbian times to South America via Polynesian seafarers, but this is disputed.
- 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.
- Phoenicians spread chickens along the Mediterranean coasts as far as Iberia.
Farming
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. The Sunday roast is often called the UK’s national dish, check out our roast dinner recipes for Sunday roasts that stand out at Jamie Oliver.
Farming
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. These domesticated chickens spread across Southeast and South Asia where they interbred with local wild species of junglefowl, forming genetically and geographically distinct groups.
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.
Hens of some breeds can produce over 300 eggs per year; the highest authenticated rate of egg-laying is 371 eggs in 364 days. During the Hellenistic period (4th–2nd centuries BC), in the southern Levant, chickens began to be widely domesticated for food. 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. The domestic chicken has subsequently hybridised with grey junglefowl, Sri Lankan junglefowl and green junglefowl; a gene for yellow skin, for instance, was incorporated into domestic birds from the grey junglefowl (G. sonneratii). Chickens are descended primarily from the red junglefowl (Gallus gallus) and are scientifically classified as the same species. Wild junglefowl can fly, whereas domestic chickens and their flight muscles are too heavy to allow them to fly more than a short distance.
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. Chickens are featured widely in folklore, religion, literature, and popular culture. The chicken was the first bird species to have its genome sequenced. 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.
