By Ian Steadman, Wired UK

The Khoe-San people of southern Africa have been recognised as one of the earliest-formed distinct human genetic groups for several years now, but new research appears to peg them as the earliest split from the main human family tree so far discovered.

[partner id="wireduk" align="right"]While homo sapiens evolved roughly 200,000 years ago, it appears that the Khoe-San people branched off and went their separate way around 100,000 years ago, according to research in the journal Science. That divergence, reports Live Science, comes far earlier than the human migration out of Africa, and also predates the migration into the area of other early human branches such as the Bantu or Pygmies who now live in the surrounding regions.

The geneticists, led by Carina M Schlebusch from Uppsala University, analysed around 2.3 million single-nucleotide polymorphisms (SNPs) from a sample of 220 southern Africans from 11 ethnic groups for genetic variations. The result was a noticeable split between the group who we now know as the Khoe-San and the rest of humanity dating back 100,000 years.

The Khoe-San (also spelled Khoisan, Khoesaan and Khoesan) live mainly in southern Africa, with their own distinct cultures, lifestyles and physical characteristics compared to the Bantu ethnic groups that surround them. The Khoe-San are largely divided into two groups – foragers and keepers of livestock – and their languages include distinctive click noises that aren't found in the languages of their neighbours. Genetic adaptations were found among the Khoe-San DNA which are associated with skeletal development – a finding which may explain why they are noticeably taller than Bantu groups.

Any reasons why the split occurred are unknown. It is however likely that the harsh, dry climate and geography of Africa during that era played a part in forcing communities into isolation from one another.

Source: Wired.co.uk