Archaeologists have uncovered 20 Stone-Age skeletons in and around a rock shelter in Libya’s Sahara desert, according to a new study.
The skeletons date between 8,000 and 4,200 years ago, indicating that the burial site was used for millennia.
“It must have been a place of memory,” said study co-author Mary Anne Tafuri, an archaeologist at the University of Cambridge. “People throughout time have kept it, and they have buried their people, over and over, generation after generation.”
About 15 women and children were buried in the rock shelter, while five men and juveniles were buried under giant stone heaps called tumuli outside the shelter during a later period when the region turned to desert.
The findings, detailed in the March issue of the Journal of Anthropological Archaeology, suggest that the culture changed with the climate.
From about 8,000 to 6,000 years ago, the Sahara desert region, called Wadi Takarkori, was filled with scrubby vegetation and seasonal green patches. Rock art depicts ancient herding animals, such as cows, which require much more water to graze than the current environment could support.
To date the skeletons, Tafuri measured the remains for concentrations of isotopes, or molecules of the same element with different weights. The team concluded that the skeletons were buried over four millennia, with most of the remains in the rock shelter buried between 7,300 and 5,600 years ago.
The males and juveniles under the stone heaps were buried starting 4,500 years ago, when the region became more arid. Rock art confirms the dry-up, as the cave paintings began to depict goats, which need much less water to graze than cows.
The ancient people also grew up not far from the area where they were buried, based on a comparison of isotopes in tooth enamel, which forms early in childhood, with elements in the nearby environment.
The findings suggest the burial place was used for millennia by the same group of people and revealed a divided society. The exclusive use of the rock shelter for female and sub-adult burials points to a persistent division based on gender.
One possibility is that during the earlier period, women had a more critical role in the society, and families may have even traced their descent through the female line. But once the Sahara began its inexorable expansion into the region about 5,000 years ago, the culture shifted, and men’s prominence may have risen as a result.
The region as a whole is full of hundreds of sites yet to be excavated, and there is a need to protect the fragile region, which has been closed to archaeologists since the revolution that ousted dictator Moammar el Gadhafi.