In the mid-19th century, German explorer Heinrichbath discovered prehistoric Saharan rock sculptures and sculptures while traveling through the Sahara deserts of North Africa.
Bath, considered one of Africa's great explorers, reported how one sculpture includes how a “cow” or depiction of a cow travels towards the pond and waters from it. “Some of these bulls have been executed brilliantly, with a loyalty that is hardly explained unless the artist assumes that he had the animal he carved in his eyes,” he said. I wrote it.
Bath is curious. The landscapes depicted in the sculptures and sculptures looked very different from the arid, almost vibrant desert he encountered.
Hundreds of years later, scientists will learn that these images depict life in the Sahara during African moisture (AHP).
What was the humidity in Africa?
AHP started ~14,500 years ago. It was primarily caused by changes in the orbit of the Earth's axial tilt that strengthened the African monsoon system. Moist air was drawn further north, turning the desert into a green savanna, filled with trees and dotted with large lakes. The motivation slowly turned the Sahara into a desert, ending the AHP five thousand years ago. Researchers now know that the Sahara and North Africa fluctuate more generally between wet and dry climates every 20,000 years.
The AHP ultimately promoted human settlements throughout the Sahara, leading to the spread of idyllicism. This is a transition from a hunter-gatherer lifestyle based on food production, primarily through domestication of animals and plants.
Ancient DNA analysis from archaeological sites around the world helps scientists construct more accurate pictures of the past of genetic histories and demographics of various regions and populations. However, the process of extracting and analyzing DNA from Saharan sites has proven historically challenging. The harsh conditions mean that DNA is rarely preserved.
In 2019, mitochondrial DNA (mtDNA) was analyzed from the ruins of two female individuals extracted from the Takalkori rock shelter in the Tadrato Acasus Mountains in southwestern Libya. The remains are estimated to be around 7,000 years old, making this study the first successful ancient DNA analysis from green Sahara herders.
MtDNA is passed only by the mother and does not change much from generation to generation. Therefore, using it to infer population dynamics can provide a limited view of the past.
Currently, a collaborative team of researchers is obtaining the first genome-wide data from the same two women.
“Two factors allowed us to generate DNA data from one of the harshest climates on the planet. First of all, the people on this site were very well preserved and one of the oldest natural mummies in the world. Dr. Harald Ringbauera population geneticist at the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) and a co-author of the study, told Technology Networks.
“This revealed a whole new insight into who the Green Sahara idyllics were and where they came from,” Ringbauer added.
The ancient North African genome rewrites the genetic history of the Sahara
According to Ringbauer, long-standing hypotheses suggest that green Sahara idyllics were born from people in sub-Saharan Africa or the Eastern Mediterranean and Nile Valley.
However, Takarkori Rock Shelter's personal ancestors paint another picture.
“The ancient genomes revealed that they were part of a previously unknown North African lineage, which was clear and isolated. Though this lineage was extinct, the present North Africans still have a significant portion of this ancestor, highlighting their unique heritage,” Lingbauer said.
The women are also associated with foraging people in Tafort Caves in eastern Morocco, with 15,000 years old ruins being sequenced in previous studies. These individuals lived during the Ice Age before the AHP.
Interestingly, the female Takalkori rocks and the individuals in the Taffort cave are equally distant in terms of their relationship with sub-Saharan African lineage. Despite Sahara's greening, gene flow between North Africa and sub-Saharan individuals appears to have been limited despite conflicting with previous hypotheses.
Takalkori women also showed a 10-fold decrease in Neanderthal DNA compared to people living outside of Africa. They have more Neanderthal DNA than modern sub-Saharan Africans.
“Our findings suggest that early North African populations were largely isolated, but received traces of neanderthal DNA due to gene flows from outside of Africa.” I said Advanced Author Professor Johannes KlausDirector of MPI-EVA.
“Our research challenges previous assumptions about the history of the North African population and highlights the existence of a deeply rooted, long-term genetic lineage.” mpi-eva. “The findings reveal how idyllicism spreads across the green Sahara, not through cultural exchanges, rather than on a large scale.”
This study not only changes understanding of North African ancestors and early pastoral communities, but also shows important findings in ancient DNA research.
It shows how far the field has come, successfully extracting and analyzing genome-wide data from ruins preserved in one of the world's most harsh environments. “The extreme Sahara climate is a unique challenge for ancient DNA. However, using cutting-edge ancient DNA technology allowed us to squeeze out sufficient genetic data for analysis,” concluded Ringbauer.
About interviewees
Dr. Harald Ringbauer is Population geneticists who develop and apply calculators analyze genetic data. His important research is the ancient DNA of humans. This sector is growing rapidly. Now, thousands of human genomes from the past are made public every year. Ringbauer is developing new ways to study the human past, in order to study these ancient genomes and learn about past populations and social structures. Currently he works at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, where he leads a research group in the Department of Archaeology.
