[Vaquero]

Here’s the deal. 10-12k years ago the coastline was 100+ miles from where it is now. As people tend to inhabit the coast more than inland, this is where we will find the first Americans. Possibly some from the Solutrean hypothesis

[SunkenCiv]

Also, during the glaciation, the lower the altitude (or latitude), by and large, the warmer the temperatures.

[SunkenCiv]

Naturally the studies are being done on inland bodies of water rather than the continental shelves where the prehistoric navigators first came and went.