The story begins 10,000 years ago in a jungle in Asia and ends today in kitchens all over the world.
Chicken is the universal food of our era, crossing cultural boundaries with ease. With its mild taste and uniform texture, chicken presents a blank canvas for the national flavours of almost any cuisine. However, until the introduction of large-scale industrial production in the 20th century, the economic and nutritional contribution of chickens was small. Chickens were considered domestic birds that were useful to humanity, but unlike other animals such as the horse or the ox, they did little to change the course of history. Nonetheless, the chicken has inspired contributions to culture, art, cuisine, science and religion over the millennia. Chickens were, and still are, a sacred animal in some cultures. The hen is a worldwide symbol of nurturing and fertility. The rooster is a universal sign of masculinity.
The domesticated chicken has a complicated family tree stretching back 10,000 years. Recent DNA testing has shown that the chicken's wild ancestor is the red junglefowl. The bird's resemblance to modern chickens is seen in the red feathers on top of its head, the red flesh around its mouth, and its distinctive call in the morning. The females of this breed protect their eggs in the same way modern-day chickens do, and they make the same clucking sounds. In its habitat, which stretches from north-eastern India to the Philippines, the red junglefowl looks on the forest floor for insects, seeds and fruit, and flies up to nest in the trees at night. That is about as much flying as it can manage, a trait that made it relatively easy for humans to capture and domesticate it. However, the red junglefowl is not the sole ancestor of the modern chicken. Scientists have identified three closely related species that might have bred with the red junglefowl. Precisely how much genetic material these other birds contributed to the DNA of domesticated chickens is unknown. Recent research suggests that modern chickens inherited at least one trait their yellow skin-from the grey junglefowl of southern India.
Once chickens were domesticated, cultural contact, trade, migration and territorial conquest resulted in their introduction to different regions of the world over several thousand years. Chickens arrived in Egypt around 1750 BC as fighting birds and additions to zoos. Drawings of the birds decorated royal tombs containing treasures intended for the afterlife. However, it took another 100 years before chickens became popular among ordinary Egyptians.
During this period, Egyptians mastered the technique of artificial incubation, freeing hens to lay more eggs. Eggs hatch in three weeks only if the temperature remains around 38 degrees Celsius. They must be turned several times a day, and humidity must remain stable. Egyptians constructed large oven-like complexes with corridors and vents to control heat. These methods were kept secret for centuries.
Around the Mediterranean, archaeologists have uncovered chicken bones dating from about 800 BC. Chickens were considered a delicacy among the Romans, who developed culinary practices such as omelettes and stuffing birds. European farmers later adopted methods to fatten chickens, including feeding them bread soaked in wine. However, the chicken's status declined after the fall of the Roman Empire, and chicken farms disappeared. Birds returned to their former size.
Well into the 20th century, chickens played a minor role in diet and the economy. Production remained small-scale until antibiotics and vitamins were added to chicken feed, allowing birds to be raised indoors. This marked the rise of factory farming. Factory farming increased both supply and demand. Modern chickens convert grain into protein with great efficiency. Less than one kilogram of feed produces 400 grams of chicken, compared to three kilograms for the same amount of beef. A chick can now reach two kilograms in six weeks.
Chickens are also popular as pets. In the USA, exotic and heritage breeds are increasingly kept in backyards and sold for significant sums of money. Overall, the chicken's global success story spans evolution, agriculture and cuisine, with chickens now outnumbering humans nearly three to one.