I just lowered my brower screen and found a notepad screen with another source that I cut and pasted because it looked interesting in the discussion above:

FOX, CARLES LALUEZA. 1996. "Mitochondrial DNA haplogroups in four tribes from Tierra del Fuego-Patagonia: Inferences about the peopling of the Americas." Human Biology 68(6):855-871.

It seems some of these studies show that groups in South America came straight across the ocean from east or west, not on a long trek down through North and Central America. This may be a text that discusses that.

SRS