The 2018 Moreno-Mayar paper proposed a specific demographic model for the founding of the Americas based on the USR1 genome and comparison with previously published ancient and modern genomes.

The model had several key components.

First, it proposed that the founding population of the Americas — the group that entered the hemisphere from Beringia and eventually gave rise to all Native American populations — was a single founding population, not multiple independent founding groups.

The diversity within the founding population, the model suggested, reflected differentiation that occurred within a single population that had been isolated in Beringia during the standstill period.

Second, within this founding population, the model identified two main branches.