Long-Time Investigation of African Tribes

Khoe-San are subsets of a tribal configuration that split off from the rest of the human genome more or less 100kya and/or as late as 35 thousand years ago. Hit the link above for some complex stuff on this radical discovery. Khoe-San are the two tribes who used to be called Bushmen living in the god-forsaken Kalahari desert between Namibia & South Africa. Here is the abstract:

The history of click-speaking Khoe-San, and African populations in general, remains poorly understood. We genotyped ∼2.3 million SNPs in 220 southern Africans and found that the Khoe-San diverged from other populations ≥100,000 years ago, but structure within the Khoe-San dated back to about 35,000 years ago. Genetic variation in various sub-Saharan populations did not localize the origin of modern humans to a single geographic region within Africa; instead, it indicated a history of admixture and stratification. We found evidence of adaptation targeting muscle function and immune response, potential adaptive introgression of UV-light protection, and selection predating modern human diversification involving skeletal and neurological development. These new findings illustrate the importance of African genomic diversity in understanding human evolutionary history.

UPDATE Here's an article in The Financial Times to explain rather poorly what this is and means.