Genomic evidence for the Pleistocene and recent population history of Native Americans

TLDR

The timing and route of the first peopling of the Americas remain contentious, with evidence that ancestral Native Americans split into two basal genetic branches around 13 ka, one now widespread across North and South America and the other confined to North America. Ancient and modern genome‑wide data show that all present‑day Native Americans descend from a single Siberian migration wave that entered the Americas no earlier than 23 ka after at most an 8 ka isolation in Beringia, that subsequent gene flow introduced East Asian and, more distantly, Australo‑Melanesian ancestry, and that putative Paleoamerican relict groups such as the Mexican Pericues and South American Fuego‑Patagonians are not directly related to modern Australo‑Melanesians.

Abstract

Howand when the Americas were populated remains contentious. Using ancient and modern genome-wide data, we found that the ancestors of all present-day Native Americans, including Athabascans and Amerindians, entered the Americas as a single migration wave from Siberia no earlier than 23 thousand years ago (ka) and after no more than an 8000-year isolation period in Beringia. After their arrival to the Americas, ancestral Native Americans diversified into two basal genetic branches around 13 ka, one that is now dispersed across North and South America and the other restricted to North America. Subsequent gene flow resulted in some Native Americans sharing ancestry with present-day East Asians (including Siberians) and, more distantly, Australo-Melanesians. Putative "Paleoamerican" relict populations, including the historical Mexican Pericues and South American Fuego-Patagonians, are not directly related to modern Australo-Melanesians as suggested by the Paleoamerican Model.