The ancient origins, anatomical, linguistic and genetic distinctiveness of southern African San and Khoikhoi people are variously described as the world’s first or oldest people; Africa’s first or oldest people, or the progenitors of all Asian phenotypes and the first people of South Africa.
They are in fact two evolutionarily related but culturally distinct groups of populations that have occupied southern Africa for up to 140,000 years. Their first-people status is due to the fact that they commonly retain genetic elements of the most ancient Homo sapiens. the KhoiSan are the genetically distinctive source of anatomical andphenotypical features of Asians. These include light brown or golden brown to sepia-coloured skin, the presence of epicanthic eye folds, prominent cheekbones and diminutive stature.
The DNA evidence used to discover the human genetic “footprints” that characterise the KhoiSan, and other diverging populations, is today easily put together. Forensic pathologists use it to determine an unidentifiable corpse’s population group. This process has been popularised on television shows such as CSI and Bones.
This DNA evidence connecting these people to Asians as a whole comes from multiple sources including: Y chromosome polymorphisms inherited without recombination along male lineages;single nucleotide polymorphisms, or SNPs, from nuclear DNA; and most especially from mitochondrial DNA.
Mitochondria are organelles within a cell that have their own independent DNA separate from that in the nucleus that determines an organism’s external appearance and physiology. They are involved with cellular respiration and nothing more.
Mitochondrial DNA enables the identification of clear genetic links between different human population groups that have evolved over time without interference. This is due to a specific component of mitochondrial DNA evolving at a faster rate compared to the majority of nuclear DNA. Additionally, mitochondrial DNA is passed down exclusively from the mother, avoiding any mixing with paternal DNA during reproduction. It suggested by DNA evidence that Homo sapiens were in China at least 20,000 years earlier than previously believed and left their genetic African footprint as they spread around the world.
The story their DNA tells is as follows. About 140,000 years ago modern African human populations from East and Central Africa moved southwards and expanded into western southern Africa (simultaneously some moved into Asia migrating toward what is present day India). The probable nearest living relatives of these southward moving source populations are:Mbuti pygmies, San people, and the Hadzabe people of Tanzania.
About 3000-3500 years ago – there was a second movement of from the north into southwestern Africa. They gave rise to the pastoral Khoikhoi precursors to the Khoi-san people.
This second group of carried within its genome bits of Eurasian-sourced – and even some Denisovan – DNA derived from surviving Eurasian archaic and Neanderthal trait carrying humans who had returned to Africa about 4000 years ago.Subsequent to this second migrations arrival, there was intermixing between the Khoikhoi and San. This gave rise to their close anatomical similarities despite the fact that they retained their marked cultural and linguistic differences.
About 2500 years ago – there was a third major north-to-south migration. This time it was the Bantu-speaking, black Africans into south-eastern Africa. Those “settlers” that eventually became the Xhosa peoples moved westwards and encountered the Khoikhoi, whom they drove further west and intermixed with genetically. These peopled China and South east Asia. DNA evidence shows The largest genomic study ever conducted among Khoi and San groups reveals that these groups from southern Africa are descendants of the earliest diversification event in the history of all humans - some 100 000 years ago, well before the subsequent 'out-of-Africa' migration of modern humans.
So, it is now possible for genetic evolutionary “anthropologists” to distinguish population differences among humans to infer the timing of their movements throughout the globe!
(The Khoikhoi–Dutch Wars were a series of conflicts that took place in the latter half of the 17th century in what was known then as the Cape of Good Hope, the European settlers thought of the Khoi-san as animals and used them for target practice and trophy gathering These ‘Cape’ Khoikhoi would be the first African population to bear the brunt of White settlement. Learn more at www.blackcoralinc.org)
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