柳叶刀

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    Timeline of the major painted rock art groups in Southwest China: A-A′: Jinsha River rock art; B-B′: Mangguan-Cangyuan rock art; C-C′: Zuojiang rock art Photos: Xinhua
Chinese researchers have obtained the first absolute dates for rock paintings at the Mangguan rock art site in Southwest China's Yunnan Province, pushing the known history of rock art created by prehistoric settled communities in the region back to about 4,220 years ago. The paintings also suggest cultural interactions more than 4,000 years ago between Southwest China and civilizations along the Yellow and Yangtze rivers, as well as possible exchanges with neighboring parts of Southeast Asia, including present-day Myanmar, Thailand and Vietnam, a member of the research team told the Global Times. 
The Yunnan Provincial Institute of Cultural Relics and Archaeology, in collaboration with Nanjing Normal University and other institutions, have recently made a significant archaeological breakthrough. Through systematic surveys and uranium-thorium (U-Th) dating at the Mangguan site in Gengma county, the research team obtained the first absolute dates for the site's rock paintings, tracing rock art created by prehistoric settled communities back to around 4,220 years ago.
The findings were recently published in the international journal Journal of Archaeological Science: Reports.
The Mangguan rock paintings represent one of the best-preserved prehistoric rock art sites in Yunnan. The research team presented high precision U Th dating of carbonate accretions that stratigraphically overlie the painted motifs at the Mangguan site, according to the paper published in the journal.
The dating results show that carbonate deposits overlying a human figure yielded a corrected age of 4,240 ± 19 years before present, confirming that ancient people living in the region had already produced mature figurative art at least 4,220 years ago, Wu Yun, first author of the paper and an associate researcher at the Yunnan Provincial Institute of Cultural Relics and Archaeology, was cited by the Xinhua News Agency report as saying.
Dating results from 11 samples taken from different motifs clustered between about 3,907 and 3,056 years ago. By comparison, the Cangyuan cliff paintings had previously been dated to roughly 3,800 to 2,700 years ago. The Mangguan paintings are therefore significantly older, filling an important chronological gap in the region's artistic record before the Cangyuan phase.
Shao Qingfeng, corresponding author of the paper and a professor at the School of Geography at Nanjing Normal University, told the Global Times that previous estimates dated the Mangguan rock paintings to a little over 3,000 years ago based mainly on imagery and comparisons with similar regional sites. Using microsamples of secondary carbonate deposits overlying the paintings, researchers have now obtained a precise minimum age of about 4,220 years before present without damaging the rock art.
The findings and the establishment of this chronological framework not only strengthen the archaeological foundation for studying rock art in Southwest China, but also provide a direct reference for rock art sites across Southeast Asia that have yet to undergo systematic dating, Shao said. 
The findings may also challenge long-held perceptions of Southwest China around 4,200 years ago - roughly the era of the Xia Dynasty (c.2070 BC-C.1600 BC) - and help fill a key gap in understanding the pluralistic yet integrated development of Chinese civilization. 
Shao said that while academic research has traditionally focused on the Yellow River and Yangtze River basins as cradles of early Chinese civilization, sites such as Mangguan and Cangyuan show that stable and culturally active communities also thrived in mountainous Southwest China. The newly established rock-art chronology brings an artistic dimension to the broader narrative of China's enduring cultural development. 
Moreover, stylistic similarities suggest that Southwest China maintained exchanges with the Yellow River and Yangtze River regions and with early societies in Southeast Asia, providing material evidence of cross-regional interaction more than 4,000 years ago.
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