[hinckley buzzard]

Quite likely the newly arriving Caribe Indians in the South (back in the 9th and 10th centuries) put their Northe American captives to work moving rock and raising corn

Having grown up in farm country, I remember well seeing windrows of rocks like this, put there by past farmers clearing them out of fields so they could plant. They had to put the rocks somewhere so they made piles of them along tree-lines and property lines. Some of them marked abandoned fields which had since overgrown with second growth woods, making the rocks look rather mysterious in their origins.

[muawiyah]

You can still see such work underway in Wisconsin.

However, this early American stuff was done without benefit of draft animals.