Experts question study claiming to pinpoint birthplace of all humans.

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The location of a proposed homeland for the maternal ancestors of living humans in what is now the Kalahari Desert of Botswana, and their routes out as climate changedGarvan Institute of Medical Research
▼ A new genetic study suggests all modern humans trace our ancestry to a single spot in southern Africa 200,000 years ago. But experts say the study, which analyzes the DNA of living people, is not nearly comprehensive enough to pinpoint where our species arose.
“I’m persuaded that southern Africa was an important area for human evolution,” says population geneticist Aylwyn Scally of the University of Cambridge in the United Kingdom who was not involved with the work. But, he says, studies of living people’s DNA can’t reveal the precise location of our ancestors. “It would be astonishing if all our genetic ancestry at this time arose in one small homeland.”
Modern humans arose in Africa at least 250,000 to 300,000 years ago, fossilsand DNA reveal. But scientists have been unable to pinpoint a more specific homeland because the earliestHomo sapiensfossils are found across Africa, and ancient DNA from African fossils is scarce and not old enough.
In the new study, researchers gathered blood samples from 200 living people in groups whose DNA is poorly known, including foragers and hunter-gatherers in Namibia and South Africa who speak Khoisan languages with click consonants. The authors analyzed the mitochondrial DNA (mtDNA), a type of DNA inherited only from mothers, and compared it to mtDNA in databases from more than 1000 other Africans, mostly from southern Africa. Then the researchers sorted how all the samples were related to each other on a family tree.
Confirming earlier studies, the data reveal that one mtDNA lineage in the Khoisan speakers—L0—is the oldest known mtDNA lineage in living people. The work also tightens the date of origin of L0 to about  (▪ ▪ ▪)

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chanakyakripa

Interesting article. Mitochondrial dna is the only way to backtrack the origin of Homo sapiens. Getting fossil evidence with even some amount of dna intact to work upon earlier than the date mentioned in this article is a chance factor. However since homo sapiens diversified from other branches of the Homo genus, it's probable that they did not original atr at one single place but rather diversified over a long period of time, genetically speaking.