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LEIPZIG, Germany — In a discovery that challenges our understanding of human history, scientists have successfully decoded the oldest DNA ever found in South Africa. This 10,000-year-old genetic time capsule offers a fascinating glimpse into the lives of our ancient ancestors and paints an unexpected picture of stability in one of the world’s most diverse regions.
While Europe and Asia have long been hotbeds for ancient DNA research, southern Africa — with its wealth of early human evidence — has remained largely unexplored. Now, a team of researchers from the University of Cape Town and Germany’s Max Planck Institute has cracked open this genetic treasure trove, revealing surprising connections between the past and present.
The study published in the journal Nature Ecology & Evolution focused on DNA extracted from the remains of 13 individuals found at Oakhurst rockshelter, a site near George, South Africa. Nine of these samples, dating from approximately 10,000 to 1,300 years ago, yielded enough genetic material for comprehensive analysis. This represents the oldest DNA ever recovered from South Africa.
“Oakhurst rock shelter is an ideal site to study human history, as it contained more than 40 human graves and preserved layers of human artifacts, such as stone tools, going back 12,000 years,” says Victoria Gibbon, Professor of Biological Anthropology at the University of Cape Town and co-senior author of the study, in a media release. “Sites like this are rare in South Africa, and Oakhurst has allowed a better understanding of local population movements and relationships across the landscape over nearly 9,000 years.”
What makes this discovery so intriguing is the lack of genetic change observed over millennia. Unlike many other parts of the world, where ancient DNA studies have revealed multiple waves of migration and population replacement, the inhabitants of Oakhurst showed remarkable genetic stability from the early Holocene (about 10,000 years ago) until the end of the Later Stone Age (around 2,000 years ago).
This genetic continuity persisted despite significant cultural and technological changes evident in the archaeological record. For instance, around 8,000 years ago, there was a shift from larger stone tools to smaller, more intricate ones. However, these innovations appear to have developed locally rather than being introduced by newcomers.
The study also sheds light on the complex history of admixture in the region over the last 2,000 years. Around 1,300 years ago, the researchers detected the first signs of genetic input from outside southern Africa. This coincides with the arrival of pastoralism (herding) and farming in the region. Interestingly, the genetic evidence suggests that these new lifestyles may have spread through cultural exchange before significant population mixing occurred.
Perhaps most surprisingly, the researchers found that some present-day indigenous groups in South Africa, such as the ‡Khomani and Karretjiemense, still show direct genetic links to these ancient Oakhurst hunter-gatherers. This connection persists despite centuries of disruption, including the arrival of European settlers in the mid-1600s and the subsequent colonial period.
The study paints a picture of southern Africa as a unique genetic time capsule, preserving ancestral lineages that have been lost or diluted in many other parts of the world. It challenges us to reconsider our assumptions about human population dynamics and the relationship between genetic and cultural change.
Paper Summary
Methodology
The researchers extracted DNA from teeth and petrous bones (a dense part of the skull) of ancient individuals. They then used advanced sequencing techniques to read this genetic material and compare it to modern populations. By looking at specific genetic markers and patterns of variation, they could trace relationships between ancient and modern groups, as well as estimate when different populations mixed.
Key Results
The key finding was the lack of genetic change in the Oakhurst population for nearly 9,000 years. When the researchers compared the oldest sample (about 10,000 years old) to later ones, they found no significant differences. This suggests a stable, isolated population. Only after 1,300 years ago did they see evidence of genetic input from East African and West African sources, coinciding with the spread of herding and farming. Despite this later mixing, some modern groups still show strong genetic links to the ancient Oakhurst people.
Study Limitations
The study was limited by the number of samples available and their geographic concentration at one site. While 13 individuals were sampled, only 9 yielded enough DNA for full analysis. Additionally, the methods used might not detect very small amounts of genetic mixing or changes in population size over time.
Discussion & Takeaways
This study challenges the idea that human populations are constantly changing through migration and mixing. It shows that in some cases, populations can remain genetically stable for thousands of years, even while adopting new technologies and ways of life. The research also highlights the importance of ancient DNA studies in understanding human history, especially in regions like Africa where such studies have been less common. Finally, it underscores the deep roots and unique genetic heritage of southern Africa’s indigenous peoples, providing valuable insights into human diversity and adaptation.
Funding & Disclosures
Open access funding was provided by the Max Planck Society. The study authors declare that they have no competing interests.
This article was originally published by a studyfinds.org . Read the Original article here. .