Chickens

An asteroid collided with Earth, releasing energy and airborne debris that led to the extinction of dinosaurs—and roughly 75% of all living species. However, the ancestors of modern galliforms (an order of terrestrial birds), along with those of ostriches and ducks, were one of a handful of bird groups that survived the cataclysm. North American fossils of galliform predecessors have been dated to about 85 million years ago.

While remains of junglefowl—birds essentially identical to chickens—have been dated to 5,400 BCE, the dating of hard evidence of the presence of domesticated Gallus gallus ranges from 3,600 BCE (China) to 2,000 BCE (Indus Valley of India and Pakistan) to 1350 CE (Chile). Genetic testing of bones from various sites leaves room for debate about whether pre-Columbian chickens were present in the Americas and Polynesia.

Humans in ancient Egypt not only collected eggs to be incubated in fire-warmed caves, they also built large incubators of clay brick that could hold thousands of chicks. Some of these facilities are still in use today.

Many cultures have imbued chickens with metaphysical powers, from Cuban Santeria to the Azande of Sudan. The tradition of splitting a dried wishbone dates to the Romans’ predecessors, the Etruscans. When they killed a sacred fowl, the bird’s furcula (Latin for “little fork”) was dried in the sun, and passersby simply needed to pick up the bone, stroke (rather than break) it, and make a wish.

Aristotle described the burying of birds’ eggs in dung heaps to artificially incubate them. Two-hundred years later, in De Agri Cultura, Cato the Elder—a Roman senator, historian, and agricultural enthusiast—describes the force-feeding of birds, advising farmers to, “cram chickens and geese…cakes of moistened fine wheat flour or barley flour. One crams twice a day and gives water at midday. Water should not be allowed for more than an hour.”

Alectryon, a soldier in Greek mythology, was told by Ares to warn of the arrival of the sun god, as Ares wished to be alone with Aphrodite. Because Alectryon fell asleep and the sun god saw the lovers, Ares turned Alectryon into a rooster, cursed to forever foretell the sun’s arrival. Alectryomancy—spreading seed across written letters and divining a message from a chicken’s pecking—was used to predict the succession of emperors in ancient Rome.

Ibn al-‘Awwam, a Muslim Arab farmer living in Spain, wrote The Book of Andalusian Agriculture—35 chapters describing agronomy practices, including cattle and poultry raising, gathered from across Babylonia, Greece, Syria, Rome, and Iberia. Translations into French and Spanish range over 1,000 pages.

One linguistic study reported that after the arrival of the Spanish, the Inca called the chicken “wallpa,” and the word developed multiple meanings: “god who creates,” “being a nuisance,” and “lavishly dressed men,” among others. Thereafter, “wallpa” as a Quechua root word appears in names of prominent Inca places, warriors, and royals—a linguistic transformation of the bird’s New World presence.

Sir John Sebright, a member of British Parliament and a livestock breeder, wrote “The Art of Improving the Breeds of Domestic Animals.” Sebright is best known for the bantam chicken that now bears his name, the first poultry breed to have its own specialist club. Sebright’s writings on insights gained from intentional breeding influenced Charles Darwin’s formulation of the theory of natural selection, as Darwin cited Sebright’s work in On the Origin of Species.

Through the 19th century, most domestic chickens were tended in small flocks on local farms or in backyards. As commercial interest grew, so did the desire for standardization. In 1873, the APA was founded to promote standards for the breeding of chickens and other domesticated birds. Eventually the APA became the home of purebred and exhibition hobbyists, while the expanding commercial industry focused on breeding hybrids for maximum production.

Through the 19th century, most chickens had been raised outdoors, on small farms or in backyards. The largest farms were limited by the need to allow birds sunlight access, since chickens raised without exposure to ultraviolet light would develop “leg weakness.” In the early 1920s, researchers found that adding the recently discovered Vitamin D to their diets prevented the ailment, allowing chickens to be confined to a life indoors.

In an effort to breed a chicken that yielded maximum breast meat while consuming a minimal amount of feed, the USDA worked with the A&P grocery company and industry partners to promote a nationwide breeding contest. Contestants were allowed one year to “create” a most desirable bird, then prove its viability over a two-year period, eventually shipping 60-dozen eggs each in incubators on freight cars to be hatched and judged.

Concerned about future food shortages after enduring two World Wars, US leaders sought production improvements from the nation’s scientists. In 1950, American Cyanamid researchers, testing the results of feeding chickens vitamin B12, inadvertently used a batch containing an antibiotic, Aureomycin, from which the B12 had been produced. Those birds grew 50% faster, and the following year the antibiotic was approved as a growth enabler.

In 1954, the National Chicken Council (initially the National Broiler Council) was founded to influence policy and promote commercial “broiler” production. In 1976, the American Egg Board was created to market chicken eggs as a “healthy” protein and a national grocery category. Between 1960 and 2019, per capita chicken consumption more than tripled in the United States.

In 1964, Ruth Harrison wrote Animal Machines, raising public awareness of intensive livestock practices and prompting the British government to release its first report on livestock welfare in 1965. “The Brambell Report” enumerated five freedoms that should be allowed to farm animals: “to stand up, lie down, turn around, groom themselves and stretch their limbs.” Codified in 1979, these bolstered animal-welfare standards adopted throughout Europe.

As part of a tradition of confined animals benefiting from sympathetic stories in children’s literature and film (Charlotte’s Web, Free Willy, Madagascar), at the turn of the 21st century, a purely pro-chicken story enjoyed broad commercial success. Chicken Run, the claymation feature from the makers of Wallace & Gromit, shared a barnyard flock’s perspective on life-and-death issues with an audience that might not have otherwise considered it.

Fighting birds for entertainment may have impelled domestication of Gallus gallus, with evidence of its practice found in ancient India, China, and Greece. In the US, the Animal Welfare Act of 1966 explicitly exempted birds and farm animals from cruelty protection, but subsequent amendments and farm-bill language expanded regulation of animal fighting (2003), effectively prohibited it (2007) and made attending such events a federal crime (2014).

Initially passed in 2008, Prop 2 requires egg-producing hens to be provided with enough space to engage in natural behaviors: turning around, standing upright, and spreading their wings. Later these requirements were legally extended to apply to any eggs sold (not just to those produced) within the state. Indicative of the public’s support for these improvements, the initiative received more votes than any other in California history.

In 2019, over 9.1 billion—billion with a ‘b’—chickens were slaughtered for meat in the United States. Nine billion is approximately the number of seconds that have passed since America’s second President, John Adams, was born in 1735. It is a number greater than all the fingers and toes on every American, and far greater than Earth’s entire human population. And 9 billion is still 100 million fewer than the number of chickens killed for meat in 2019.