Somewhere on the southern coast of South Africa, a single tooth sat buried in ancient cave dirt for tens of thousands of years. No one expected it to hold any secrets. Scientists had long assumed that Africa's hot climate would have destroyed any genetic material long ago. They were wrong.
An international team of researchers has now extracted DNA from that tooth, dating it to roughly 50,000 years ago — the oldest genetic material ever recovered from sub-Saharan Africa. The discovery, published in the journal Quaternary Science Reviews, suggests scientists may have dramatically underestimated what ancient treasures might still be hiding in warmer regions of the world.
The team, led by Deon de Jager, wanted to test whether it was even possible to find usable DNA in fossils from South Africa's coastal caves. They collected 320 fossil teeth and bones from six different species of wild bovids — the animal family that includes antelopes and buffalo. The fossils came from six cave and rock shelter sites along South Africa's southern coast and spanned the past 110,000 years.
Of the 144 specimens the researchers tested, 65 contained ancient DNA — a 45 percent success rate that surprised even the scientists. The team used a technique that focuses on tiny single strands of damaged DNA, which proved far more effective than older methods. This single-stranded approach extracted up to 6.7 times more genetic material than the traditional double-stranded technique.
Before this study, the oldest genome ever recovered from a wild South African animal belonged to an extinct blue antelope that lived about 9,300 years ago. The new research smashed that record. Among the successful samples, four were far older than the rest: three teeth from an extinct long-horhorned buffalo and one from a mountain reedbuck, all dating between 12,000 and 50,000 years old.
The implications stretch far beyond this single discovery. If ancient DNA can survive in South Africa's warmer climate, it may also survive in other regions previously considered hopeless for genetic research. "We show that paleogenetic studies on fauna at lower latitudes are possible," the researchers wrote. They also offered practical guidance for future scientists: specimens from the more recent Holocene period, spanning the last 12,000 years, offer the best chances of success.
For a tooth sitting quietly in a cave for 50 millennia, the wait paid off in a big way.