The Ancestors Of The First Americans
One of the most remarkable aspects of the Punín-2 man’s ancestry is what the deep history behind it involves. Rynn characterized him as “descended from an ancestral group of North Siberians and East Asians during the last ice age” — a formulation that points back to the specific population dynamics that produced the First Americans.
The ancestors of the First Americans were, roughly 20,000 to 30,000 years ago, part of the populations that inhabited the region around Lake Baikal and the broader territory of northeastern Siberia. These populations were themselves the descendants of people who had migrated eastward across Central Asia from populations in Southwest Asia and eventually from the original African homeland of all modern humans.
The specific genetic signature that distinguishes Native Americans from other populations — and that can be used to identify Native American ancestry even in ancient specimens — was formed in the ancestral population of Beringia before or during the period of the land bridge crossing. The founding population that eventually became the First Americans passed through a genetic bottleneck at this stage: the relatively small number of individuals who made the initial crossing, and who were the ancestors of all subsequent Native Americans, carried only a subset of the genetic variation that existed in the northeastern Asian populations they came from.
This founding bottleneck explains several features of Native American genetics: the reduced genetic diversity compared to most Old World populations, the specific genetic variants that are characteristic of Native Americans and not found in other populations, and the overall pattern of genetic relationships that place Native Americans as a distinct branch on the global human family tree.
The Punín-2 man, living three to four thousand years ago in the Chimborazo highlands, was fully embedded in this genetic heritage. His ancestors had been in the Americas for at least ten thousand years by the time of his birth — long enough for the specific adaptations to Andean environments, the specific cultural practices of high-altitude hunter-gatherer life, and the specific population structure of the Ecuadorian highlands to have developed.
He was, in every meaningful sense, a fully evolved Andean human — not an immigrant, not a visitor, but the product of thousands of years of human life in this specific landscape.