Abstract
The Iron Age Saghil site in Uvs Aimag (Sagil Sum), Mongolia, is a Chandman-Sagly culture site consisting of several large tombs in wooden chambers surrounded by smaller satellite graves. To investigate the kinship, social structure, and circumstances of death at this unusual site, we performed a comprehensive archaeogenetic analysis of 25 individuals. Radiocarbon indicates that the burials date to the late 5th - early 4th century BCE. Genetic analysis, based on autosomal and Y-chromosomal STR and complete mitochondrial genomes, allowed us to reconstruct a large, three-generation patrilineage buried within the two central tombs. This core family is defined by a single Y-haplotype (Q-M346), distinguishing them from a genetically diverse population in the satellite graves. Crucially, the family structure is not one of successive generations being buried in the same family vault as adults, but rather of a number of related individuals having died and been buried in what could have been the same act. We propose that the organization of these two central vaults was dictated by a specific social logic: a "tomb of established couples" (Structure 9) and a "tomb of unmarried heirs" (Structure 10), reflecting a funerary response structured by marital status and social rank within the lineage. While perimortem trauma in two males suggests potential violence, it may also reflect complex funerary preparation. These results question the nature of other Chandman-Sagly plural burials, suggesting that some may represent rapid responses to mass death events rather than long-term family mausoleums, with kinship and social standing serving as the primary organizing principles of the funerary rite.
Keywords: archaeogenetics, Y-STR, Mitochondrial DNA, Patrilineage, Chandman-Sagly culture, Iron Age, Plural burial