How Chicken got Domesticated?

Описание: https://doi.org/10.1073/pnas.1308939110
https://doi.org/10.1073/pnas.2121978119
Genetic studies suggest that domestic chickens mainly descended from red junglefowl, specifically the Gallus gallus spadiceus subspecies in Southeast Asia. The genetic divergence between these chickens and their wild counterparts occurred between 12,800 and 6,200 years ago, but this doesn't necessarily represent the start of domestication. It marks the split between the wild and domestic chicken lineages.

Reanalyses indicate that the first chickens likely came from the subspecies Gallus gallus spadiceus in southwestern China, northern Thailand, and Myanmar. The earliest confirmed chicken bones date back to around 1650-1250 BCE in central Thailand. Chickens then spread to Central China, South Asia, and Mesopotamia by the late second millennium BCE, reaching Melanesia by 700 BCE. Their western dispersal to Ethiopia and Mediterranean Europe was notably rapid.

The red junglefowl are often called "bamboo fowl" in Southeast Asian languages, in the native range these birds take advantage of cyclical bamboo flowering and seeding events. Red junglefowl also consume rice, a staple for Southeast Asian domestic chickens. As Neolithic communities in Southeast Asia adopted mixed foraging and cereal cultivation, such as cultivating rice and millet, the habitat changes attracted red junglefowl to human settlements.
The transition from primary forest to secondary vegetation due to land reclamation for cereal cultivation created a more suitable habitat for red junglefowl. They thrived in slash-and-burn agricultural systems, and the presence of cultivated fields, fallow fields, cereal harvest residues, and other human activities likely attracted them to villages. The availability of cereals created selective pressures, leading to changes in red junglefowl behavior over multiple generations, such as a relaxation of selection against larger clutch size and decreased territoriality in males.
Archaeobotanical evidence suggests that rice cultivation sites within the distribution of the likely chicken progenitor, Gallus gallus spadiceus, appeared around 2000 BCE in southern Yunnan and northeast Thailand. While cereal farming was present, there's no early evidence of domestic chicken populations. In interior zones with rainfed rice and millet cultivation, a closer relationship between people and red junglefowl is evidenced by early chicken bones at sites like Ban Non Wat and Non Nok Tha. In regions north of Yunnan, wet rice agriculture appeared as early as 4000 to 3000 BCE, but chickens only appear around 1000 BCE, indicating a delayed association between chickens and wet rice cultivation compared to other forms of cultivation in the tropical south.

The spread of chickens aligns with the development of agriculture across Asia and Africa. In South Asia, sedentism and the dominance of domesticated rice, wheat, barley, and other grains became prevalent in the Ganges plains around the second millennium BCE. This period, especially from the later second millennium BCE, corresponds with the arrival of unequivocal chicken remains in the Indian subcontinent. The introduction of domesticated indica rice around 1600-1500 BCE in the Upper and Middle Ganges, with its rainfed and fallow features, likely attracted chickens. Genomic evidence indicates that local domestic chickens in South Asia resulted from the mixing of local Gallus gallus murghi with introduced chickens from Gallus gallus spadiceus.
In Iron Age Mesopotamia, the cultivation of Chinese millets intensified after 1000 BCE, coinciding with the archaeological visibility of poultry farmingallus Irrigated rice also became established in Syria by around 1100 BCE, aligning with the broader diversification of grain crops and the emergence of poultry husbandry after the late Bronze Age collapse.

In Africa, the appearance of chickens correlates with the spread of rice agriculture. The eighth/ninth-century CE translocation of chickens to coastal Southeast Africa and Indian Ocean islands aligns with the introduction of Asian crops like rice. In the Niger Basin, archaeological evidence shows increased urbanism and widespread rice cultivation around 300-900 CE, coinciding with the first appearance of chickens in the region.
Early pictures and chicken remains in Mesopotamia and parts of Europe suggest chickens were linked with elite culture, special burials, holy places, and divine ceremonies. New discoveries show that early European chickens were respected, not eaten right away. However, these findings need further validation.

In conclusion, chickens' domestication and global spread from red junglefowl occurred relatively late compared to other farm animals. Further archaeological investigations may unveil earlier human-junglefowl connections and global chicken translocations.