Geneticists and archaeologists have finally located the historical era when modern spirited humans began their dispersal out of Africa to fill up Planet Earth: when “God created mankind in the [spiritual] Divine image, in the image of God he created them, male and female he created them, and God blessed them and said to them, “Be fruitful, increase in number; fill the earth and subdue it.” [Genesis 1:27-8]
Physically modern Homo sapiens first arose in Africa more than 300,000 years ago, but were the earliest such people also ‘just like us’ in their mental capacities. Almost all archaeologists believe people like us were living in small communities in an Ice Age refuge on the South African coast by at least 100,000 years ago.
Between around 100,000 and 70,000 years ago, these people left plentiful evidence that they were thinking and behaving like modern spirited humans – evidence of personal and religious symbolism, such as the use of pigments for body painting and for rock drawings and engravings, shell beads, and tiny stone tools called microliths that might have been part of bows and arrows.
Some of this evidence for what some archaeologists call “modern human behavior” goes back even further, to more than 150,000 years ago.
But if these achievements somehow made these people special, suggesting a direct line to the people of today, the genetics of their modern “Khoi-San” descendants in southern Africa doesn’t seem to bear this out.
Our genomes imply that almost all modern non-Africans from all over the world – and indeed most Africans too – are derived from small groups of people living not in South Africa but in East Africa, around 60,000-70,000 years ago.
There’s been no sign so far that southern Africans contributed to the huge expansion of Homo sapiens out of Africa and across the world that took place around 60,000-70,000 years ago.
But now, a team of geneticists have studied the maternally-inherited mitochondrial DNA from Africans in unprecedented detail, and have identified a clear signal of a small-scale migration from South Africa to East Africa that took place at just around 65,000 years ago. The signal is only evident today in female mitochondrial DNA.
In the rest of the genome, it seems to have been eroded away to nothing by recombination – the reshuffling of chromosomal genes between parents every generation, which doesn’t affect the female mitochondrial DNA – in the intervening millennia.
The migration signal makes good sense in terms of climate. For most of the last few hundred years, different parts of Africa have been out of step with each other in terms of the aridity of the climate.
Only for a brief period at 60,000-70,000 years ago was there a window during which the continent as a whole experienced sufficient moisture to open up a corridor between the south, the far north and the east.
And intriguingly, it was around 65,000 years ago that some of the signs of spiritual symbolism and technological complexity seen earlier in South Africa start to appear in the east.
The identification of this signal opens up the possibility that a migration of small groups of spirited people from South Africa towards the northeast around 65,000 years ago transmitted aspects of their sophisticated modern human culture to people in East Africa.
Those East African people who were biologically little different from the South Africans; their brains were just as advanced and they were cognitively ready to receive the benefits of the new spiritual and religious ideas and upgrade.
When the groups from South Africa encountered the East Africa people it started the greatest diaspora of Homo sapiens ever known – both throughout Africa and out of Africa to settle much of Eurasia as far as Australia within the space of only a few thousand years.