Before the advent of pottery making in the Amazon around 2000 BC, its inhabitants can rarely be traced, since they made tools of perishable materials. But in the dry highlands of Peru, where preservation of organic materials is excellent, crop plants have been found around 6500 BC.
They include several that came from the tropical jungles, such as chilis, suggesting that the elusive inhabitants of the Amazon had already begun cultivation.
The principal native crop of this region was manioc (cassava). This is high in carbohydrate, but has to be supplemented by protein from hunted animals and aquatic foods like fish and turtles.
Manioc has no hard parts that survive in archaeological sites, so indirect clues are used to demonstrate that it was cultivated. These include tiny flint chips from grater boards, and specific types of pottery. Large pottery vats and bowls, known from around 2000 BC at Tutishcainyo on the Upper Amazon and from other areas, suggest the making of sweet manioc beer.
By 1000 BC, wide flat pottery griddles and small firedogs indicate bitter manioc bread was being made; this is supported by finds of bowls used in processing. Other equally elusive crops probably cultivated here include yams, sweet potatoes, peanuts and chilis.
