Ancient DNA discovery in Cameroon reveals "Ghost Population" of early humans

The quest to uncover humanity’s origins often starts in Africa, where modern Homo sapiens first appeared around 250,000 years ago.

In tracing the origins of humanity, researchers often start in Africa, where Homo sapiens are believed to have first appeared around 250,000 years ago, Caliber.Az reports, citing foreign media.

 However, a significant challenge has long hindered deeper investigation into this crucial area: the harsh climate of Central Africa was once thought to be too hot and humid for ancient DNA to endure. This environmental factor has made it difficult to conduct detailed genetic analyses of prehistoric human remains in the region.

Recently, a breakthrough has emerged from Cameroon, where a burial site containing four well-preserved skeletons, dating back thousands of years, has been discovered. This find not only sheds light on the historical diversity of the region but also reveals a previously unknown "ghost population" of early humans. In a study published in Nature, geneticists and archaeologists extracted high-quality DNA samples from the inner ear bones of four children buried at the Shum Laka site, a notable archaeological location in western Central Africa. This area is known as the heartland of the Bantu languages, which underpin a vast array of African languages spoken by about a third of the continent’s population.

The researchers were surprised to find that the DNA from these children, who lived between 3,000 and 8,000 years ago, exhibited significant differences from the ancestry of modern Bantu speakers. “This finding indicates that the Bantu-speaking populations in Cameroon and elsewhere in Africa today do not directly descend from the population to which the Shum Laka children belonged,” said Dr. Mark Lipson of Harvard Medical School, the study’s lead author.

“It highlights the ancient genetic diversity in this region and points to a previously unknown population that contributed only small fractions of DNA to modern African groups.” The study revealed that the children were most closely related to hunter-gatherer groups like the Baka and Aka, traditionally known as “pygmies.” Notably, one of the samples contained a rare Y-chromosome genetic marker found almost exclusively in the same region today. 

This discovery provides scientists with a clearer picture of the diversity among African groups that inhabited this region before the Bantu migrations into the highlands. “These findings underscore how the human landscape in Africa just a few thousand years ago was markedly different from today and demonstrate the value of ancient DNA in uncovering the complex history obscured by recent population movements,” said Dr. David Reich, the senior author of the study.

The evidence of this “ghost population” emerged after comparing the children’s DNA with samples from a 4,500-year-old specimen found in Mota Cave, Ethiopia, and sequences from other ancient and contemporary Africans. This comparison led to a revised model suggesting that the origins of Central African hunter-gatherers extend back from about 200,000 to 250,000 years ago.