[SampleMan]

...when richer Anglo foods made their way to North America...

Potatoes were from South America.

Tomatoes were also a New World food.

Sugar cane came from SE Asia.

And weren't the Spanish, not the Anglos, the ones that introduced new foods to the SW United States?

[muawiyah]

Anthropologists differentiate between "North America" and "Meso America" ~ rather similar to the way they differentiate between Asia and Europe.

So, corn arrived and that spelled their doom. Suddenly they had a high carb diet!

Indians developed corn and spread the plant and the culture that went with it just all over the place ~