'Early humans began in southern Africa'
Hunter-gatherer groups in southern Africa were among the most genetically diverse populations.
A recent genetic study has revealed that modern humans might have been originated from the hunter-gatherer populations of southern Africa.
According to the study published in the Proceedings of the National Academy of Sciences, people living in southern regions of the black continent had the most genetic diversity, which indicates longevity.
Findings contradict previous studies which traced the origins of modern humans to eastern Africa, the state-run BBC reported.
"Africa is inferred to be the continent of origin for all modern human populations," the international team of researchers wrote.
"But the details of human prehistory and evolution in Africa remain largely obscure owing to the complex histories of hundreds of distinct populations."
Scientists say the study is the most comprehensive of its kind and has yielded two main results.
"One is that there is an enormous amount of diversity in African hunter-gatherer populations, even more diversity than there is in agriculturalist populations," said co-author Brenna Henn of Stanford University, California.
"These hunter/gatherer groups are highly structured and are fairly isolated from one another and probably retain a great deal of different genetic variations -- we found this very exciting," she explained.
"The other main conclusion was that we looked at patterns of genetic diversity among 27 (present-day) African populations, and we saw a decline of diversity that really starts in southern Africa and progresses as you move to northern Africa."
According to Dr. Henn, the team's modeling was consistent with the serial founder effect which shows that there is a loss of genetic variation when a new population is established by a very small number of individuals from the original, larger population.
"Populations in southern Africa have the highest genetic diversity of any population, as far as we can tell,” she said.
"So this suggests that this might be the best location for (the origins) of modern humans."
Chris Stringer, a leading paleontologist based at London's Natural History Museum, also said the new study"... suggests that the genes of the Namibian and Khomani bushmen (southern Africa), Biaka pygmies (Central Africa) and the Sandawe (East Africa) appear to be the most diverse, and by implication these are the most ancient populations of Homo sapiens."
"This is a landmark study, with far more extensive data on... hunter gatherer groups than we have ever had before, but I am cautious about localizing origins from it," Stringer added.
He said that although the range of these groups is limited nowadays, rock paintings by ancient populations linked to the Bushman suggest that they were once very diverse.
"It seems more likely that the surviving hunter-gatherer groups are now localized remnants of populations that formerly ranged across much of sub-Saharan Africa 60,000 years ago," he said.
TE/AKM
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