What group of people adapted to the life in the Kalahari increasing their knowledge of the natural world?

The Bushmen, San, Basarwa, ǃKung or Khwe are indigenous people of the Kalahari Desert, which spans areas of South Africa, Botswana, Namibia and Angola. They were traditionally hunter-gatherers, part of the Khoisan group, and are related to the traditionally pastoral Khoikhoi. Starting in the 1950s through the 1990s they switched to farming. Genetic evidence suggests they are one of the oldest, if not the oldest, peoples in the world - a "genetic Adam" according to Spencer Wells, from which all humans can ultimately trace their genetic heritage.