Ancient human species still in our genes

All of us in Europe carry genes from this human species, writes Richard Collins

A Neanderthal man

“And Cain went out from the presence of the Lord and dwelt in the land of Nod on the East of Eden. And Cain knew his wife and she conceived and bare Enoch, and he built a city.”

BUT who was Cain’s wife? Unless Adam had a daughter that Cain took with him, the only females available would have been Neanderthals.

Our species, Homo sapiens, appeared in Africa around 200,000 years ago. The first modern humans remained in the ‘dark continent’ for countless millennia. Then, about 70,000 years ago, some of them travelled northwards. The only viable route out of Africa was around the eastern perimeter of the Mediterranean to the Middle East and Turkey. The pioneers, the archaeologists say, settled in Western Asia. Later on, people moved eastwards from this region, establishing colonies from India to Australia. About 45,000 years ago, another group headed westwards towards Europe.

On arrival in Western Asia, our ancestors discovered that they were not alone; Neanderthals had been living in the region for countless millennia. These distant cousins were more heavily-built than the immigrants. They had equally big brains but differently-shaped heads. Their eyes were further apart and their foreheads sloped backwards above huge noses. Neanderthal limbs were shorter, but stronger, than those of the new arrivals. Their women may not have been everything a lonely love-sick Cain would have desired but ‘in a storm, any port is haven’. We don’t know how the long-established residents responded to the arrival of the blow-ins, but scientists writing in Genome Biology and Evolution think that interbreeding took place between the two groups soon after the first encounters. DNA analysis suggests that ‘Neanderthals contributed genetic material to modern humans via multiple admixture events’, say the authors.

Inhabitants of the Northern Hemisphere today carry Neanderthal genes, some of which are beneficial. Researchers, analysing human genomes from various parts of the world, say that people carry genes ‘related to metabolism and immune system responses’ inherited from Neanderthals long ago. ‘Broadly speaking, these are functions that can have an impact on health’, according to the experts; they confer resistance to celiac disease and malaria. But the extent to which an individual has alien genes seems to depend on where his or her remote ancestors lived. Sub-Saharan people have none: their ancestors never encountered Neanderthals.

Western Asia was a crossroads from which settlers from Africa dispersed eastwards and westwards. It was there, the scientists think, that interbreeding first took place.

Trying to verify this, they studied the genomes of ten present-day European African and Western Asian Druze people. Those of various other populations, including 16 from Western Turkey, were also examined. Oddly, the results showed that people from Asia have, on average, fewer Neanderthal genes than those living in Europe.

Does this mean that the Western Asian interbreeding hypothesis is wrong? Not necessarily.

This is evidence, they suggest, of a constant flow of people coming into the region. People, with no Neanderthal genes, arriving from Africa may have diluted the gene pool in the transit area. Settled communities to the East and West, living side by side with Neanderthals and not receiving infusions of ‘new blood’, would be likely to accumulate more of the alien genes.

‘He has made from one blood every nation of men to dwell on all the face of the earth’. (Acts 17: 26-28.)

  • Recep Ozgur Taskent et al. Variation and functional impact of Neanderthal ancestry in Western Asia. Genome Biology and Evolution. 2017.


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