It is believed that modern humans developed 200,000 years ago in Africa, south of the Sahara Desert, and as evolved beings wanted to explore. However the when and the how modern humans crossed the Sahara and scattered from the country is controversial. Scientists are divided between an exodus through Egypt and Ethiopia to Eurasia.
It is believed that modern humans migrated from Africa through Egypt to Eurasia according to genomic reports. Modern humans most likely began migrating 50,000 to 60,000 years ago states Luca Pagani from the Wellcome Trust Sanger Institute in Hinxton UK. It was Pagani’s colleagues that observed the genomes of 125 Ethiopians and 100 Egyptians to see if there were still traces of the migration in the current citizens of those countries.
Then the genomes were compared with the DNA from South and East Asians and Europeans specifically Han Chinese Tuscan and Gujarati Indians. This data was also distinguished with DNA from modern West Africans, south of the Sahara and should show the ancient sub-Saharan gene pool.
If modern humans left through Ethiopia, then Eurasian genomes would be more common with theirs. If the migration went through Egypt, than Eurasian genomes would be common with them. In the study to control for recent migration in and out of Ethiopia, Egypt, Eurasia and Africa, researchers used computer simulation to show later movement and controlled for already anticipated genomic effects. The Egyptian genomes were most similar to the Eurasians’ showing that modern humans went through Egypt. The findings of this study agrees with other evidence says Michael Petraglia from Oxford University.
Eurasians intermixed with Neanderthals after leaving their homeland. Neanderthals stayed in the Levant when people migrated out of the country. Petraglia ackowledges there is no evidence supporting that people lived further south.
University of Porto Portugal’s Luisa Pereira, does not fully trust the new results. Pereira says the study depended too much on computer simulations and that could cause them to miss some genetic mixing that has occurred along the way. She does believe that it makes sense that Egyptian genomes would have more in common with Eurasians, as Egypt is close to the region.
Pagani, who was not present for this study, believed the computer simulations were strong. His team has tried introducing a fake ‘error’ so Ethiopian genomes would be more like Eurasians’ regardless Egyptian genetics proved to be more similar.
Pagani believes that the research generated by his team is the first all-inclusive set of unbiased genomic data collected. If Pagani’s research is correct it would advance the understanding of the human evolutionary background, culturally and geographically. Pagani’s research is freely available to benefit other anthropological and medical studies.
Some recent studies have acknowledged the idea that modern humans in Ethiopia had left Africa through Bab-el-Mandeb which is a strait that links the Horn of Africa with the Arabian Peninsula. However, an international study from researcher Pagani might have proven otherwise.
Pereira’s critical eye suggests that more evidence will need to be gathered before any agreement can be made on routes taken by modern humans out of the country. A study published May 29, in the American Journal of Human Genetics states that there are genome correlations between Eurasians and Europeans, suggesting that Pleistocene emigrants went through Egypt.
The out-of-Africa theory is the most widely accepted model to explain the movement of modern humans to Eurasia. It presupposes that after the evolution of the first modern humans, there was a significant migration out of the country. Paleoanthropologists agree that the migration occurred approximately 60,000 years ago, but they do not agree on the direction of the exodus. Some believe many paths were taken out of Africa and others believe there is just one path used. The prehistoric migrants, may have used bridges or simple rafts to cross over but they were the first modern humans to populate Europe and Asia. There is evidence from fossils suggesting Neanderthals had already inhabited the continent.
Previous research shows that the migration from Africa began 40,000 to 70,000 years ago. A more recent study indicated that modern humans could have begun leaving Africa 130,000 years ago and spread out from there in several waves.
Scientists suggested two routes for leaving Africa. The northern route through Egypt and Sinai and the southern path that travels through Ethiopia and Arabia. The evidence gathered currently for any migratory path is still inconclusive.
The southern route possibility out of Africa did not go through Arabia, as Ethiopians are not genetically similar to Eurasians. However researchers discovered that Egyptians were genetically similar to Eurasians. This suggests that the northern route out of Africa was used the most.
Researchers believe that Eurasians genetically deviated from Egyptians 55,000 years ago, from Ethiopians 65,000, and from West Africans 75,000. The details of this study will be available online Thursday June 4, in the American Journal of Human Genetics.
By Jeanette Smith
New Scientist: Gene Study Shows Humans took Egyptian Path out of Africa
Christian Science Monitor: Early Human left Africa Through Egypt, Study Says
NBC News: Modern Humans Trekked out of Africa via Egypt, DNA Suggests
The Independent: Early Humans Migrated Out of Africa Through Egypt Rather Than Ethiopia, New Study Says
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