According to this press release, a new paper reports on the discovery of a 10,000 year old SNP on the Y-chromosomes of men from Tanzania and southern Africa. It will be appearing in PNAS‘ online early edition tomorrow (DOI: 10.1073/pnas.0801184105). The SNP is thought to have originated in eastern Africa,
“The team analyzed Y chromosomes from men in 13 populations in Tanzania in eastern Africa and in the Namibia-Botswana-Angola border region of southern Africa. They discovered a novel mutation shared by some men in both locations, which implied those men had a common ancestor. Further analysis showed the novel mutation arose in eastern Africa about 10,000 years ago and was carried by migration to southern Africa about 2,000 years ago. The mutation was not found in Bantu-speakers, suggesting that a different group – Nilotic-language speakers – first brought herds of animals to southern Africa before the Bantu migration.
This new genetic evidence correlates well with pottery, rock art and animal remains that suggest pastoralists – herders who migrated to new pasture with their flocks – first tended sheep and cattle in southern Africa around 2,000 years ago. The genetic finding also helps explain linguistic similarities between peoples in the two regions.”
You may know that previous research based upon archaeology, skeletal morphology, linguistics and mtDNA has suggested that prehistoric people in eastern and southern Africa were virtually isolated between 30,000 and 1,500 years ago, with only two known migrations between the regions during that time frame. One of the authors of this paper, Brenna Henn, acknowledges this over at the Spitton. She writes,
“Our new genetic study, while still supporting the archaeological record for the timing and place of the origins of pastoralism in sub-Saharan Africa, puts a new twist on the current thinking. It suggests that a small group of men actually migrated into southern Africa about 2,000 years ago. These men probably married into local hunter-gatherer populations, contributing their livestock and cultural knowledge of pastoralism.”