what geographical feature limited contact between sub-saharan africa and the outside world
Sub-Saharan Africa Since probably 3500Â BCE,[4][5] 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 interrupted by only the Nile in Sudan, though the Nile was blocked by the river's cataracts. The Sahara pump theory explains how flora and fauna (including Homo sapiens) left Africa to penetrate the Middle East and beyond. African pluvial periods are associated with a Wet Sahara phase, during which larger lakes and more rivers existed.[6]
My Ántonia
Strait Straits are the converse of isthmuses. That is, while a strait lies between two land masses and connects two larger bodies of water, an isthmus lies between two bodies of water and connects two larger land masses.
The empire on which the sun never sets In the modern era, due to the British Overseas Territory of the Pitcairn Islands, the sun has not yet set on all British territories. [26]