DNA Sheds Light On The Iron Age Log Coffin Culture In Pang Mapha, Thailand

Jan Bartek - AncientPages.com - The Iron Age in the highland region of Pang Mapha, northwestern Thailand, was characterized by a unique mortuary practice known as the Log Coffin culture. Between 2,300 and 1,000 years ago, individuals were buried in large wooden coffins on stilts, primarily within caves and rock shelters.

Deciduous and evergreen forests thrive in the limestone karst formations of Thailand's northwestern highlands. This region has a vast network of caves and rock shelters interspersed throughout the mountains. Remarkably, in over 40 Mae Hong Son province caves, large wooden coffins mounted on stilts, dating between 2,300 and 1,000 years ago, have been discovered. These coffins, dating back to the Iron Age period, were meticulously crafted from single teak trees, with some reaching several meters in length. They feature intricate carvings of geometric, animal-like, or human-like shapes adorning the handles at both ends, showcasing the refined craftsmanship of the era.

DNA Sheds Light On The Iron Age Log Coffin Culture In Pang Mapha, Thailand?

Caves and rock shelters dot the mountains in the northwestern highlands of Thailand. Over 40 in Mae Hong Son province contain wooden coffins on stilts, dating back 1,000 - 2,300 years. Credit: Selina Carlhoff

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 conducted a comprehensive analysis of DNA samples from 33 buried individuals across five Log Coffin sites. Their findings reveal fascinating insights into the connections between individuals from the same and different sites. The evidence suggests that the associated people formed a large, well-connected community, where genetic relatedness played a significant role in the mortuary rituals.

"Our research examines the relationship between humans and their environments in the seasonal tropics. One crucial aspect is the exploration of the social structure of these prehistoric communities, as well as explaining their connections with other pre-Neolithic, Neolithic and post-Neolithic groups in this region," says Rasmi Shoocongdej, an archaeologist and senior author of the study.

A comprehensive study has explored the genetic profiles of the Log Coffin-associated communities and the connections between individuals buried in different caves. Scientists analyzed the DNA of 33 ancient individuals from five Log Coffin sites, enabling the first detailed examination of the structure of a prehistoric community from Southeast Asia.

The recovered ancient genomes provide invaluable insights into these past communities, shedding light on their daily lives and cross-regional connections. As highlighted by Selina Carlhoff, the first author and a researcher at the Max Planck Institute for Evolutionary Anthropology, this project exemplifies how ancient DNA can significantly contribute to understanding prehistoric communities, their lifestyles, and their cross-regional connections.

DNA preservation in tropical regions poses significant challenges, limiting ancient population genetic studies from Southeast Asia. Most previous studies have focused on single individuals or small groups representing a specific country and period, only identifying broad patterns such as the genetic admixture of farmers from the Yangtze River valley in southern China with the local Hòabìnhian hunter-gatherer-associated gene pool during the pre-Neolithic period.

However, the current study has identified two distinct farmer-associated ancestries among the Log Coffin-associated individuals. One is connected to the Yangtze River Valley, while the other is linked to the Yellow River Valley in China. Interestingly, while previously published individuals from Myanmar, Laos, and Vietnam also carry the Yellow River-related ancestry, it was absent in Bronze and Iron Age individuals from Ban Chiang in northeastern Thailand.

These genetic differences mirror cultural differences between the two regions, such as mortuary practices and diet, suggesting separate influence spheres and connections to distinct initial migration routes during the Neolithic period.

DNA Sheds Light On The Iron Age Log Coffin Culture In Pang Mapha, Thailand

In Thailand’s Iron Age Log Coffin culture, coffins were made from a single teak tree and decorated with refined carvings of geometric or animal shapes on both ends. Credit: Selina Carlhoff

The study provided a groundbreaking community-level analysis of Southeast Asian archaeology. To investigate relationships between individuals, the authors utilized genetic regions that are identical in two individuals, inherited from a common ancestor. This analysis of identical-by-descent (IBD) blocks helped trace complex biological relatedness patterns within a site and across regions, a novel approach in archaeogenetic studies of Southeast Asia. The research identified close genetic relatives buried in the same cave system, such as parents and children or grandparents and grandchildren, forming a cluster of closely related individuals. However, this cluster was more distantly connected to all other individuals buried at the site.

While this suggests a selection of burial places based on genetic relatedness, the more distant genetic relationships between Log Coffin sites, low level of consanguinity, as well as high mitochondrial and low genome-wide diversity indicate that the Log Coffin-associated groups were rather large and constantly connected to each other across different river valleys.

See also: More Archaeology News

"This result is highly significant, since wooden coffins were also used in other archaeological cultures all over Southeast Asia. Comparing relatedness patterns and cross-regional genetic connections would be a fascinating future collaborative project which could potentially explain the cultural dynamics and population interactions within Southeast Asian and other regions," says Rasmi Shoocongdej.

Further archaeogenetic studies conducted in collaboration with local scholars, as well as novel admixture modeling and dating techniques, will shed more light on the emerging patterns. These advanced methods will enable direct connections between the genetic data and archaeological findings, allowing for a more comprehensive understanding and validation of existing hypotheses.

The study was published in Nature Communications

Written by Jan Bartek - AncientPages.com Staff Writer