Indian people have lived in the Yosemite region for as long as 8,000 years. By the mid-nineteenth century,when native residents had their first contact with non-Indian people, they were primarily of Southern Miwok ancestry. The native people of Yosemite developed a complex culture rich in tradition,religion, songs, and political affiliations. Making use of the varied local ecosystems,they used plant and animal resources to the best of their abilities. The pattern of oaks and grassland noted by early visitors to Yosemite Valley is probably a direct result of the intentional burning of underbrush practiced by native people.