Chickens were first domesticated over 8,000 years ago in Southeast Asia. They originated from junglefowl species, pheasant-like birds that once thrived worldwide. People initially kept them for decoration and eggs.
Over time, certain species were selectively bred for larger size, increased egg production, and better meat quality. Distinct lineages emerged, such as the Indian gamefowl, Malay, Shamo, and Cornish. These foundational breeds underwent generations of cross-breeding and selective breeding, producing the wide range of chicken breeds seen today.