The most ancient branch of anatomically modern humans are the Khoe-San of southwestern Africa, an ethnic group who speak languages characterized by frequent clicks.
Genomic evidence places their geographical isolation from other humans at around 100,000 years ago, even before the human migration from Africa to Europe and Asia, according to a study published today on the website of the Washington-based Science magazine. Today they live mainly in Namibia, South Africa and Botswana.
The study, which tested the DNA of 220 people from 11 southern African populations, showed that the Khoe-San’s genetic divergence pre-dates the “out of Africa event” of about 70,000 years ago when anatomically modern humans migrated to Europe and Asia, Mattias Jakobsson, one of the researchers, said on a conference call yesterday. The khoe-San have traditionally lived a nomadic, hunter-gather lifestyle while some became herders.
Scientists from South Africa, Sweden, the U.S. and France studied approximately 2.3 million samples of DNA from each individual. The Khoe-San’s genetic makeup differs from that of other southern African populations, like the Bantu-speakers, a broad group of languages that includes South Africa’s Zulu and Shona of Zimbabwe, according to the study.
“The Khoe-San retained their ancestral genomes,” Himla Soodyall, a researcher on the study from Johannesburg-based University of the Witwatersrand, said in a conference call yesterday. “They drifted and remained isolated until 3,000 to 3,500 years ago when they came into contact with West Africans.”