The Pre-Clovis evidence and its implications for the founding models have also continued to develop.

The White Sands dates, confirmed by multiple independent methods, establish that people were in the interior of North America during the Last Glacial Maximum — well before the earliest Clovis sites and well before the USR1 burial.

This evidence forces the question of whether the White Sands people were related to the founding population that produced USR1 and the other well-documented early Americans, or whether they represent an earlier, separate founding event.

No ancient genome from a pre-Clovis context has been successfully analyzed, so the genetic character of the White Sands people and their relationship to the USR1 lineage and to other ancient Americans remains unknown.