Khoisan hunter-gatherers have been the largest population throughout most of modern-human demographic history
Kim, H.Lim.; Ratan, A.; Perry, G.H.; Montenegro, A.; Miller, W.; Schuster, S.C.
Nature Communications 5: 5692
2014
ISSN/ISBN: 2041-1723 PMID: 25471224 DOI: 10.1038/ncomms6692Document Number: 451946
The Khoisan people from Southern Africa maintained ancient lifestyles as hunter-gatherers or pastoralists up to modern times, though little else is known about their early history. Here we infer early demographic histories of modern humans using whole-genome sequences of five Khoisan individuals and one Bantu speaker. Comparison with a 420 K SNP data set from worldwide individuals demonstrates that two of the Khoisan genomes from the Ju/'hoansi population contain exclusive Khoisan ancestry. Coalescent analysis shows that the Khoisan and their ancestors have been the largest populations since their split with the non-Khoisan population ~100-150 kyr ago. In contrast, the ancestors of the non-Khoisan groups, including Bantu-speakers and non-Africans, experienced population declines after the split and lost more than half of their genetic diversity. Paleoclimate records indicate that the precipitation in southern Africa increased ~80-100 kyr ago while west-central Africa became drier. We hypothesize that these climate differences might be related to the divergent-ancient histories among human populations.