Ancient DNA helps researchers elucidate the structure of a prehistoric community from Southeast Asia
A mortuary practice known as Log Coffin culture characterizes the Iron Age of highland Pang Mapha in northwestern Thailand. Between 2,300 and 1,000 years ago, individuals were buried in large wooden coffins on stilts, mostly found in caves and rock shelters. An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and the Prehistoric Population and Cultural Dynamics in Highland Pang Mapha Project in Bangkok, Thailand, has now analyzed DNA from 33 buried individuals from five Log Coffin sites, and found fascinating new connections between individuals from the same and different sites. The associated people seem to have been a large, well-connected community, where genetic relatedness played a significant role in the mortuary ritual.
Carlhoff, S., Kutanan, W., Rohrlach, A.B. et al. Genomic portrait and relatedness patterns of the Iron Age Log Coffin culture in northwestern Thailand. Nat Commun 14, 8527 (2023). https://doi.org/10.1038/s41467-023-44328-2
The Iron Age of highland Pang Mapha, northwestern Thailand, is characterised by a mortuary practice known as Log Coffin culture. Dating between 2300 and 1000 years ago, large coffins carved from individual teak trees have been discovered in over 40 caves and rock shelters. While previous studies focussed on the cultural development of the Log Coffin-associated sites, the origins of the practice, connections with other wooden coffin-using groups in Southeast Asia, and social structure within the region remain understudied. Here, we present genome-wide data from 33 individuals from five Log Coffin culture sites to study genetic ancestry profiles and genetic interconnectedness. The Log Coffin-associated genomes can be modelled as an admixture between Hòabìnhian hunter-gatherer-, Yangtze River farmer-, and Yellow River farmer-related ancestry. This indicates different influence spheres from Bronze and Iron Age individuals from northeastern Thailand as reflected by cultural practices. Our analyses also identify close genetic relationships within the sites and more distant connections between sites in the same and different river valleys. In combination with high mitochondrial haplogroup diversity and genome-wide homogeneity, the Log Coffin-associated groups from northwestern Thailand seem to have been a large, well-connected community, where genetic relatedness played a significant role in the mortuary ritual.