"Potatoes originated in the Andes mountains of Peru and Bolivia and have been cultivated for at least 2400 years." Peru has literally hundreds of varieties of potatoes. This makes sense to me. As for sheep, again I agree. Sheep really aren't so big in N. America. Not nearly so much as cows and pigs. The south, the Andean mountains, goatherds and the like...that makes sense, imho. As for pigs, I think pigs were more European, Asian, and I think N. African. Basically, North America didn't have a lot of those resources, until they were brought over at one point or another. So are we going off what was in North America, or what was brought? It's like wheat. Wheat was brought over by the English, I believe, but now its a fairly major crop.