A new study claims that modern humans first made their way out of Africa along a northern route.
Previously scientists believed that the first humans traveled across Ethiopia in order to leave the continent, but a new study tells a different story, writes Kamal Nayan for News Everyday.
Genetic analysis informs conclusion
“Two geographically plausible routes have been proposed: an exit through the current Egypt and Sinai, which is the northern route, or one through Ethiopia, the Bab el Mandeb strait, and the Arabian Peninsula, which is the southern route,” said Dr. Luca Pagani, of the Wellcome Trust Sanger Institute and the University of Cambridge.
“In our research, we generated the first comprehensive set of unbiased genomic data from Northeast Africans and observed, after controlling for recent migrations, a higher genetic similarity between Egyptians and Eurasians than between Ethiopians and Eurasians,” he continued.
In order to determine which route our ancestors took, scientists sequenced the genomes of 225 people from northeast Africa, including 100 Egyptians and 125 Ethiopians. This data was then compared to the DNA of Han Chinese, Gujarati Indians and Tuscan Italians.
Most human ancestors used northern route
If Ethiopians were found to be more genetically similar to Eurasians, it would have meant that the southern route was the main highway out of Africa. However, the researchers found more genetic similarities between Egyptians and Eurasians, showing that the northern route was the one that most of our ancestors took.
It is estimated that the genetic diversification of Eurasians from Egyptians occurred 55,000 years ago, while it happened 65,000 years ago from Ethiopians.
As well as providing good data on the evolutionary past of Eurasians, the researchers have also contributed an extensive public catalog of genome sequences for the populations of Ethiopia and Egypt. “This information will be of great value as a freely available reference panel for future medical and anthropological studies in these areas,” Dr. Pagani added.
The full results of the study were published in the American Journal of Human Genetics.
Scientific research in the region has also revealed that a new human ancestor lived in the Afar region of Ethiopia between 3.3 million and 3.5 million years ago. A paper on Australopithecus deyiremeda was published yesterday in the journal Nature.
