Genetic Data Suggests That Early Modern Humans Migrated From South to East Africa

Science Daily is running a story that supports the idea that modern humans migrated from South to East Africa before exiting the continent.  Up until recently, all of the evidence seemed to suggest that South Africa, while having evidence of modern humans at Klasies Rivers Mouth, Border Cave and other sites, did not contribute to the migration out of Africa.  That has changed.

The Huddersfield-Minho team of geneticists, led by Professor Martin Richards at Huddersfield and Dr Pedro Soares in Braga, along with the eminent Cambridge archaeologist Professor Sir Paul Mellars, 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 that time, around 65,000 years ago. The signal is only evident today in the 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 mitochondrial DNA — in the intervening millennia.

Before going further, it is worth noting that purveyors of the mtDNA evidence have been burned before by incorrectly using the programs to input the information. Originally, those results supported a hard-line Out-of-africa model of modern human origins (Stringer and Andrews 1988), a model we now know is incorrect. Onward.The paper is available through Scientific Reports, which is open-access.  What is missing from this hypothesis is good human fossil material from South Africa which is between 160 and 200 ky.  The most current remains we have are around 120k.  More work needs to be done on this.