Karoo Karoo biome. The number of mainly succulent plant species is very high for an arid area of this size anywhere in the world. The Nama Karoo biome is located entirely on the central plateau mostly at altitudes between 1000 and 1500 m. It incorporates nearly the whole of the historical and geographical Great Karoo, but also includes a portion of southern Namibia's Namaqualand, and South Africa's Bushmanland" (both local geographical names, not names of biomes). It is the second-largest biome in South Africa, and forms the botanical transition between the Fynbos biome to the south and the savannah biome to
Karoo sediments. This exposed the dolerite sills, which were more resistant to erosion than the Karoo sediments, forming one of the most characteristic features of the Karoo landscape, namely the flat topped hills, called "Karoo Koppies". The geology of the region bears no resemblance to that of the Great Karoo (see the diagram on the left, of a NS geological cross-section through the Little and Great Karoos). The valley is an integral part of the Cape Fold Mountain Belt, with the two ranges on either side composed of extremely hard, erosion-resistant, quartzitic sandstone belonging to the 450- to 510-million-year-old Table Mountain