Ancient DNA reveals a family ossuary and long-distance migration on the Pacific coast before the Inca Empire

AI interpretationAI-generated

Ancient DNA from Peru's Chincha Valley reveals coastal migration and a family ossuary before the Inca Empire.

This study analyzes genomes from 21 individuals buried in a family ossuary in Peru's Chincha Valley. They share ancestry with groups about 700 km north, showing long-distance coastal migration by the 13th century. Early migrants had unmixed ancestry, but later generations intermarried with neighboring coastal groups. The family practiced close-kin marriage. A Bayesian model using DNA and diet data provided precise dating, showing population continuity from the 13th to 15th centuries, alongside traditions of cranial modification and red pigment use.

• Long-distance migration along the Pacific coast began by the 13th century CE, with earliest migrants having unmixed ancestry.
• Subsequent generations intermarried with neighboring coastal groups, creating admixed ancestry.
• A family ossuary reveals consanguineous endogamy and close-knit coastal interaction networks that shaped pre-Inca society.

Sample interpretation

All 21 individuals were from the Chincha Valley. Y-chromosome analysis resolved 12 samples, all belonging to haplogroup Q, with Q-Z5910 (4 samples) and Q-Y805 (3) most common. Mitochondrial DNA showed B2 (5), B2b (2), C1b (2), D1 (2), and A2 (1). These lineages are typical of ancient and modern Indigenous South Americans, supporting local continuity and coastal connections.

For genealogy enthusiasts

For ancestry enthusiasts, this study shows how ancient DNA can trace family structures, migration, and marriage patterns in pre-Inca Peru. It highlights the power of combining genetics with archaeological context to reveal complex social networks along the Pacific coast.