Then, about 7000 B.C., within the space of a few generations, they switched abruptly to herding domesticated goats and sheep and to growing einkorn, pulses, and other cereal grasses.

"Life is very different in Kenya. People live a poor life here on the grasslands. They can't afford TVs, cars or mobile phones. They make a living mainly by herding cows and sheep." Marco says.

Dry farming, irrigation farming, and the cattle and sheep herding are the main activities of the Great Plains of the American West.