There are billions of chickens across the world and a new genomic analysis indicates they were first domesticated in northern Southeast Asia or Southern China more than 9,000 years ago, Science reports.
The Kunming Institute of Zoology's Ya-Ping Zhang and his colleagues sequenced the genomes of a global sampling of 627 domestic chickens, 142 red jungle fowl, 12 green jungle fowl, two gray jungle fowl, and four Ceylon jungle fowl. As they report in Cell Research, the researchers found chickens were initially derived from the red jungle fowl subspecies Gallus gallus spadiceus that is currently found in southwestern China, Thailand, and Myanmar. They further estimate that that domestication took place about 9,500 years ago. After domestication and spread, chickens were interbred with other, local jungle fowl, such as G. g. murghi.
These findings, Science notes, contrast with previous archaeological studies that have indicated an origin for chickens in northern China or Pakistan. The Smithsonian Institution's Melinda Zeder tells Science the paper is "fascinating" and that it shows "the domestication and dispersal story is more complicated than we thought." She further suggests genetic and archaeological data be combined to put together a fuller picture of how chicken domestication occurred.