Karoo are exposed. These are locally known as the Cango Group, but are probably continuous with the Malmesbury Group that forms the base of Table Mountain on the Cape Peninsula, and similar outcrops in the Western Cape. In the Little Karoo, the outcrop is composed of limestone, into which an underground stream has carved the impressively extensive Cango Caves. The Great Karoo and Little Karoo lie almost entirely within two of South Africa’s eight botanical biomes, namely the Succulent Karoo biome and the Nama Karoo biome, both of which, like the Karoo Geological System, are more extensive than the geographical or
Karoo desert ephemerals, spaced 50 cm or more apart, and becoming very sparse going northwards into Bushmanland and, from there, into the Kalahari Desert. The driest region of the Karoo, however, is its southwestern corner, between the Great Escarpment and the Cederberg-Skurweberg mountain ranges, called the Tankwa Karoo, which receives only 75 mm of rain annually. The eastern and north-eastern Karoo are often covered by large patches of grassland. The typical Karoo vegetation used to support large game, sometimes in vast herds. Today, sheep thrive on the xerophytes, though each sheep requires about 4 ha of grazing to sustain itself. The