[tallhappy]

If all the American Indian tribes came from the same Bering Sea crossers how come the ones in S. America became human sacrificers and the N. American Indians did not?

A lot of assumptions on your part.

Yet, I would suggest -- if there is any validity to your theory -- the drug use (psychoactive plant use) contributed a lot.

[piasa]

In the midwest, the artwork of the Spiro mounds people and their contemporaries deteriorated markedly at one point- it may have something to do with the increase in the number of jimson weed seeds found in their habitations.