One of the frameworks that has been proposed for the founding of the Americas is the Beringian standstill hypothesis.

This model proposes that the ancestral population of the Americas spent an extended period — possibly thousands of years — isolated in the Beringian region, neither returning westward into Asia nor spreading southward into the Americas, before the southward expansion into the ice-free Americas began.

The evidence for this standstill comes partly from genetics.

The specific pattern of genetic diversity in Native American populations — including the particular combinations of haplogroups found and the specific mutations shared across different Native American groups — is more consistent with an extended period of population isolation before the southward expansion than with a rapid, continuous movement from northeastern Asia straight through Beringia and into the Americas.

If the standstill hypothesis is correct, the ancestral population of the Americas spent thousands of years in Beringia, accumulating the specific genetic characteristics that now distinguish Native Americans from other human populations.