origin and spread of chicken (Gallus Gallus) The question throughout the ancient world is one of the most puzzling questions about Eurasian livestock. The lack of agreement regarding the time and center of origin is due to problems in morphological identification, lack of direct dating, and poor preservation of thin and fragile bird bones. In a new study, archaeologists examined ancient chicken eggshells from 13 different sites spanning 1,500 and a half years. Their results indicate that chickens were widely domesticated in southern Central Asia from the 4th century BC to the Middle Ages and may have dispersed along the ancient Silk Road.

Dr Kari Peters, a researcher at the Max Planck Institute for Geoanthropology, said: “With the introduction of genetic and molecular techniques, the debate over the origin and spread of domesticated chickens has intensified in recent years. “An old debate over a mysterious bird is being reignited.” colleague.

“Historical sources demonstrate that chickens were prominent in southern Europe and southwest Asia by several centuries BC.”

“Similarly, art historical depictions of chickens and anthropomorphic rooster-human chimeras are recurring motifs in Central Asian prehistoric and historical traditions. It remains a mystery when this critically important bird spread along the trans-Eurasian exchange route.”

“Experts agree that domestication traits evolved in island populations of junglefowl in South Asia. Red Jungle Fowl (Gallus Gallus Subspecies Spediceus) It is located somewhere in a vast range from Thailand to India. ”

“However, scholars have also presented widely differing dates and routes of spread, and part of this confusion may be due to unclear identification of birds in ancient art, and the morphological characteristics of chicken bones that have not been identified. This is due to the overlap with that of wild birds.

“Furthermore, their fragile, hollow bones and eggshells are much less likely to be preserved, recovered, and identified than in other animals.”

In a new study, the authors found evidence that egg production was prominent in Central Asia starting in the centuries BC and continuing into the Middle Ages.

“We show that chickens were widely domesticated in Central Asia from about 400 BC to 1000 AD, and likely dispersed along the ancient Silk Road,” the researchers said.

“The abundance of eggshells further suggests that the birds were laying eggs out of season.”

“It was this ability to produce large numbers of eggs that made domestic chickens so attractive to ancient peoples.”

To reach these conclusions, researchers collected tens of thousands of eggshell fragments from 13 sites along the Silk Road's main Central Asian corridor.

They then used a biomolecular analysis method called ZooMS to determine the source of the eggs.

Similar to genetic analysis, ZooMS can identify species from animal remains such as bones, skin, and shells, but it relies on protein signals rather than DNA. This makes it a faster and more cost-effective option than genetic analysis.

“Our study shows the potential of ZooMS to shed light on human-animal interactions in the past,” said Dr. Peters.

“The identification of these shell fragments as chickens and their abundance throughout the sediment layers at each site led us to an important conclusion: this bird was They must have been laying eggs more frequently than their wild ancestor, the red junglefowl, which nests once every year.''In a year, they typically lay six eggs per clutch. ”

“This is the earliest evidence of seasonal spawning loss seen in the archaeological record,” said Dr. Robert Spengler, a researcher at the Max Planck Institute for Geoanthropology.

“This is an important clue for a deeper understanding of the human-animal mutualism that led to domestication.”

team's paper It was published in the magazine nature communications.

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C. Peters other. 2024. Archaeological and molecular evidence for ancient chickens in Central Asia. Nat Commune 15, 2697; doi: 10.1038/s41467-024-46093-2