A new study says modern humans may have originated from southern Africa. The study has challenged the age-old view that people came from the eastern part of the continent. An extensive genetic study, published in 'Proceedings of the National Academy of Sciences' journal, has showed that hunter-gatherer populations in the region had greatest degree of genetic diversity, which is an indicator of longevity. According to the study's co-author Dr Brenna Henn of Stanford University, the study reached two main conclusions. One is that there is an enormous amount of diversity in African hunter-gatherer populations, even more diversity than there is in agriculturalist populations. The other main conclusion was that genetic diversity among 27 present-day African populations starts in southern Africa and progresses as one moves to northern Africa.