sentences:  Even under the hot conditions of the Kalahari Desert, many different species survive; in fact the country has more than 2500 species of plants and 650 species of trees.Vegetation and its wild fruits are also extremely important to rural populations living in the desert and are the principal source of food, fuel and medicine for many inhabitants.Three national parks and seven game reserves that are wildlife shelters occupy 17% of the land area of Botswana.