From chicken biryani to khao mun gai, chicken and rice is a winning combination all over the world. But the two are more inextricably linked than even the chefs realized. A couple of new archaeological studies suggest that without rice, chickens may never have existed.
The work reveals that chickens may have been domesticated thousands of years later than scientists thought, and only after humans began growing rice within the range of wild birds of the red jungle, in Thailand or the vicinity of the Southeast Asian peninsular, says Dale Serjeantson, an archaeologist at the University of Southampton who was not involved in the research. Studies, he says, have “dismantled many of the old myths about the origins of chickens.”
Charles Darwin proposed that the chickens descended from the red jungle chicken, a colorful tropical bird of the pheasant family, because the two are very similar. But agreeing with him was difficult. Five varieties of jungle birds range from India to northern China, and small chicken bones are rare at fossil sites.
In 2020, a genome study of 863 living chickens confirmed that the jungle chicken rooster rooster spaedicus the subspecies was the ancestor of live chickens; chickens share more of their DNA with that subspecies than other types of jungle birds. This in turn restricted the domestication site to Southeast Asia. Researchers have proposed fossils as the first 8,000-11,000-year-old chickens in northern China and Pakistan. But living bird genetics couldn’t narrow the window for domestication, says geneticist Ming-Shan Wang, a postdoctoral fellow at the University of California, Santa Cruz, first author of the genetic study. And they haven’t been able to get enough ancient DNA from fossilized chickens to pinpoint the date. Thus the paleo-anatomist Joris Peters of the Ludwig Maximilian University of Munich collaborated with Greger Larson, a bioarchaeologist at the University of Oxford, an expert in animal domestication. The duo organized an international team that initiated a comprehensive reassessment of chicken bones, their dates and records on them, from over 600 archaeological sites around the world. In a separate study, the team directly dated chicken bones found in Western Eurasia and North Africa.
They found that the oldest chicken bones likely came from a site called Ban Non Wat in central Thailand, where farmers grew rice from 3,250 to 3,650 years ago, the team reports today in Proceedings of the National Academy of Sciences. Farmers buried many skeletons of young members of the genus Rooster as grave goods alongside other domestic animals – strong evidence that these birds were domesticated chickens rather than wild jungle birds. The researchers propose that the rice seeds attracted wild jungle birds to rice paddies, where the birds nested in thickets on the edge of fields and got used to humans.
While scientists have traced the trail of chicken bones across Asia to the Middle East and Africa, they have found a “surprising” correlation between the widespread cultivation of dry rice, millet and other grains and appearance. chickens. Chickens appeared around 3,000 years ago in northern China and India, the team found, and around 2,800 years ago in the Middle East and northeast Africa. Studies that found the first chickens were flawed, the team argues, because either the fossils weren’t chickens or the dates were inaccurate.
To find out when the chickens first entered Europe, team members directly reshaped the bones of 23 of the first proposed chickens in Europe and Asia. The first chickens in Europe were found at an Etruscan site in Italy 2,800 years ago, the team reports Antiquity today.
The study is also supported by historical documents, including the Bible. “Chickens don’t appear in the Old Testament,” says study lead author Naomi Sykes, an archaeologist at the University of Exeter. “They entered the scene in the New Testament.”
It took another 1000 years for the chickens to spread north to Great Britain (with the Romans), Scandinavia and Iceland. Subtropical birds likely had to adapt to colder climates, says Cardiff University archaeologist Julia Best, who was involved in both studies.
However, it is only recently that humans have begun to think of birds primarily as food. Initially, people traded them as exotic goods, prized for their feathers, colors, and sonorous singing at first light, based on how they were depicted in art and buried as valuable burial items, Sykes says. The first chickens were smaller, she notes, and not a major source of meat. But the team’s review shows that around 500 years after chickens are introduced to each new place, they lose their special status and become a regular food.
Studies show that “the dispersal of domestic chickens is a more recent event than previously predicted,” says Masaki Eda, a zooarchaeologist at the University of Hokkaido.
However, Eda says he’d like to see follow-up research to make sure the bones in Thailand are definitely domesticated chickens, not wild jungle birds buried with humans. He also wants researchers to examine other sites in Southwest Asia to connect the dots showing where and how chickens were domesticated as rice and millet farming spread across Eurasia.
Although chickens were domesticated later than other animals, they became the most successful domestic species on the planet, Larson says. Today, with a strength of 80 billion, they are 10 to 1 more than us. “It’s not just about chickens or rice,” says Sykes. “How humans relate to chickens is a shining lens for understanding how humans relate to the natural world.”