Sub-Saharan Africa or Subsahara is the area and regions of the continent of Africa that lie south of the Sahara. Geopolitically, in addition to the African countries and territories that are situated fully in that specified region, the term may also include polities that only have part of their territory located in that region, per the definition of the United Nations UN. The African Union AU uses a different regional breakdown, recognising all 55 member states on the continent—grouping them into five distinct and standard regions.
However, while they are also member states of the Arab League , the Comoros , Djibouti , Mauritania , and Somalia and sometimes Sudan are all geographically considered to be part of sub-Saharan Africa. Since around BCE , [ 7 ] [ 8 ] the Saharan and sub-Saharan regions of Africa have been separated by the extremely harsh climate of the sparsely populated Sahara, forming an effective barrier that is interrupted only by the Nile in Sudan, though navigation on the Nile was blocked by the Sudd and the river's cataracts.
The Sahara pump theory explains how flora and fauna including Homo sapiens left Africa to penetrate Eurasia and beyond. African pluvial periods are associated with a " Wet Sahara " phase, during which larger lakes and more rivers existed. Geographers historically divided the region into several distinct ethnographic sections based on each area's respective inhabitants. The geographers drew an explicit ethnographic distinction between the Sudan region and its analogue Zanj, from the area to their extreme east on the Red Sea coast in the Horn of Africa.
In the 19th and 20th centuries, the populations south of the Sahara were divided into three broad ancestral groups: Hamites and Semites in the Horn of Africa and Sahel related to those in North Africa, who spoke languages belonging to the Afroasiatic family; Negroes in most of the rest of the subcontinent hence, the toponym Black Africa for Africa south of the Sahara [ 20 ] , who spoke languages belonging to the Niger-Congo and Nilo-Saharan families; and Khoisan in Southern Africa , who spoke languages belonging to the Khoisan family.
Sub-Saharan Africa has a wide variety of climate zones or biomes. South Africa and the Democratic Republic of the Congo in particular are considered megadiverse countries. It has a dry winter season and a wet summer season. According to paleontology , early hominid skull anatomy was similar to that of their close cousins, the great African forest apes , gorilla and chimpanzee.
