<P> Before the expansion of farming and pastoralist African peoples, Southern Africa was populated by hunter - gatherers and earlier pastoralists . </P> <P> It is thought that Central African Pygmies and Bantus branched out from a common ancestral population c. 70,000 years ago . Many Batwa groups speak Bantu languages; however, a considerable portion of their vocabulary is not Bantu in origin . Much of this vocabulary is botanical, deals with honey collecting, or is otherwise specialised for the forest and is shared between western Batwa groups . It has been proposed that this is the remnant of an independent western Batwa (Mbenga or "Baaka") language . </P> <P> Proto - Khoisan - speaking peoples, whose descendants have largely mixed with other peoples and taken up other languages; a few still live by foraging (often supplemented by working for neighbouring farmers) in the arid regions around the Kalahari desert, while a larger number of Nama continue their traditional subsistence by raising livestock in Namibia and adjacent South Africa . </P> <P> Historically south east Africa was once inhabited by southern Cushites and the most predominant one were the Azania who dominated from Kenya towards Tanzania . They were also other Cushitic tribes who were native to Tanzania whom were Iraqw, Gorowa, Alagwa, Burunge, Asa, and Kw'adza . These southern Cushites were native and ruled south east Africa until the wave of Bantu expansion that wiped them out and assimilated the rest and today they are extremely tiny in their own ancestral land . Also, there are an existing southern Cushites who are known as Tutsi native to Rwanda and Burundi, although they share a nation with the Hutus who are not native in the lands they are living today . </P>

How did the bantu migrations affect africa's population