Ancient mitochondrial DNA provides high-resolution timescale of the peopling of the Americas

Summary

Archaeological evidence indicates human presence as far as southern Chile and Argentina by 14.6-14.0 kya (thousand years ago), shortly after the Pleistocene ice sheets blocking access from eastern Beringia began to retreat. Genetic estimates of the timing and route of entry have been constrained by the lack of suitable calibration points and low genetic diversity of Native Americans. We sequenced 92 whole mitochondrial genomes from pre-Columbian South American skeletons dating from 8.6-0.5 kya, allowing a detailed, temporally calibrated reconstruction of the peopling of the Americas. The data suggest a small population entered the Americas via a coastal route around 16 kya, having been isolated in eastern Beringia for ~3-10 ky after separation from eastern Siberian populations. Following a rapid movement throughout the Americas, limited gene flow in South America resulted in marked phylogeographic structure, which persisted through time. Finally, European colonization caused a high extinction rate of pre-Columbian lineages, with all the ancient haplotypes detected in this study being absent from modern datasets.

This Resource is Part of the Following Collections

• Society for American Archaeology 81st Annual Meeting, Orlando, FL (2016)

Keywords

Spatial Coverage