Sub-Saharan Africa is the term used to describe the area of the
African continent which lies south of the
Sahara desert. Geographically, the
demarcation line is the southern edge of the
Sahara Desert.Since around 4,000 years before present, the north and sub-Saharan regions of Africa have been separated by the extremely harsh climate of the sparsely populated Sahara, forming an effective barrier interrupted by only the
Nile River. The peoples south of the Sahara (excluding the Nile Valley) developed in relative isolation from the rest of the world. The modern term sub-Saharan corresponds with the standard representation of North as above and South as below. Tropical Africa and Equatorial Africa are alternative modern labels, used for the distinctive ecology of the region. However, if strictly applied, this term would exclude South Africa, most of which lies outside the Tropics.
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