History of agriculture
Wild grains were collected and eaten from at least 20,000 BC. From around 9500 BC, the eight Neolithic founder crops – emmer wheat, einkorn wheat, hulled barley, peas, lentils, bitter vetch, chick peas, and flax – were cultivated in the Levant. Rye may have been cultivated earlier but this remains controversial. Rice was domesticated in China by 6200 BC with earliest known cultivation from 5700 BC, followed by mung, soy and azuki beans. Pigs were domesticated in Mesopotamia around 11,000 BC, followed by sheep between 11,000 BC and 9000 BC. Cattle were domesticated from the wild aurochs in the areas of modern Turkey and Pakistan around 8500 BC. Sugarcane and some root vegetables were domesticated in New Guinea around 7000 BC. Sorghum was domesticated in the Sahel region of Africa by 5000 BC. In the Andes of South America, the potato was domesticated between 8000 BC and 5000 BC, along with beans, coca, llamas, alpacas, and guinea pigs. Bananas were cultivated and hybridized in the same period in Papua New Guinea. In Mesoamerica, wild teosinte was domesticated to maize by 4000 BC. Cotton was domesticated in Peru by 3600 BC. Camels were domesticated late, perhaps around 3000 BC.
Eastern Agricultural Complex
The region of this early agriculture is in the middle Mississippi valley, from Memphis north to St. Louis and extending about 300 miles east and west of the river, mostly in Missouri, Illinois, Kentucky, and Tennessee. The oldest archaeological site known in the United States in which Native Americans were growing, rather than gathering, food is Phillips Spring in Missouri. At Phillips Spring, dating from 3,000 BCE, archaeologists found abundant walnuts, hickory nuts, acorns, grapes, elderberries, ragweed, bottle gourd, and the seeds of "Cucurbita pepo", a gourd with edible seeds that is the ancestor of pumpkins and most squashes. The seeds found at Phillips Spring were larger than those of wild "C. pepo". The agency for this change was surely human manipulation. Humans were selecting, planting, and tending seeds from plants that produced larger and tastier seeds. Ultimately, they would manipulate "C. pepo" to produce edible flesh.