>>17797478
>Authors say " R1b was most likely introduced through admixture during the post-1492 European settlement of North America", but I'd remain skeptical of that unless proof was somehow provided.

Politically correct academics say that, except the DNA evidence pretty clearly shows an ancient maritime migration from Europe. If it was post-Columbian, then the greatest concentration of R-DNA would be in Central and South America, not the backwoods of N.America.