7,000-Year-Old Mummies

The Sahara is a vast expanse of sand where the fight for survival can be brutal. But there was a time in the distant past when it was green and flourishing.

Back between 14,000 and 5,500 years ago, during the African Humid Period, the Sahara had enough water to support a way of life, rather than being one of the driest places on Earth. At that time, it was a savannah where early humans settled for the favorable farming conditions. Among those people was a mysterious sub-group who lived in what is now southwestern Libya. Genetically, they should have been Sub-Saharan. But modern analysis shows that their genes don’t reflect that.

A team of researchers found two 7,000-year-old naturally preserved mummies of Neolithic female herders at the Takarkori rock shelter. Usually, genetic material does not preserve well in arid conditions, but in this case, there was enough fragmented DNA to give some insights into their past and clear up some of the mystery of human populations in the Sahara.

The Takarkori individuals don’t share DNA with modern humans. The majority of their ancestry stems from a previously unknown North African genetic lineage that diverged from sub-Saharan African lineages about the same time as modern humans roamed outside of Africa. But the Takarkori people appear to have remained isolated throughout most of their existence.

These Takarkori individuals were close relatives of 15,000-year-old foragers from the Taforalt Cave in Morocco. Both the Takarkori and the Taforalt people have about the same genetic distance from Sub-Saharan groups that existed at that time. This suggests there was not much gene flow between Sub-Saharan and Northern Africa at the time. Also, the Taforalts have half the Neanderthal genes of non-Africans. The Takarkori have ten times less. But, both of them still have more Neanderthal DNA than other Sub-Saharan peoples who were around at the time. Although the Tarkarkori apparently had less contact with Neanderthals than their more western brethren, they must have had more contact than other groups in their region. There are also traces of evidence of the Tarkarkori mixing with farmers from the Levant (the east coast of the Mediterranean Sea). But otherwise, the genes of the Takarkori reveal they were mostly isolated. Although genetically close to Northwestern African foragers like the Taforalt, they were distinct from Sub-Saharan populations.

It appears there was not much genetic exchange in the Green Sahara during the African Humid Period. It was thought that farming spread through the region by migrations, but this research suggests another explanation. Perhaps pastoralism spread through cultural diffusion into a deeply divergent, isolated North African lineage that was widespread in Northern Africa during the late Pleistocene epoch. In other words, farming spread through the exchange of practices between cultures rather than the mixture of people from migrations.

The Takarkori may have inherited their genes from a hunter-gatherer group from before animals were domesticated and farming began. Despite being hunter-gatherers, their ancestors made advances in making pottery, baskets, and tools made of wood and bone. They also seemed to stay in one place for longer periods of time.

Possibly the Takarkori stayed isolated because of the diversity of environments in the Green Sahara. These ranged from lakes and wetlands to woodlands, grasslands, savannas and even mountains. Such differences were probably barriers to interactions between human groups.

Elsewhere in the Sahara, there might be additional mummies or artifacts that could tell us more about life in the desert before it dried out.

 

https://www.msn.com/en-us/news/technology/scientists-found-7-000-year-old-mummies-in-the-desert-that-don-t-share-dna-with-modern-humans/ar-AA1N0sir?ocid=hpmsn&cvid=68d560f961774dfd9a9711556f780d2a&ei=40