STATES CHRONICLE – The Neanderthal genes which were present in our DNA had disappeared due to evolution. It is well-known that modern humans and Neanderthals had the same origin, having a common ancestor. The Neanderthals lived in the colder weather of Eurasia, developing big skulls, strong hands, and broad chests. The modern human lived in Africa, growing narrow heads, slender limbs, and a protruded chin.
Approximately 50,000 years ago the two species have met and mated. In the past years, scientists have analyzed the effect of these species’ interbreeding. After thorough research, experts revealed that 4% of the genes of non-Africans are categorized as having a Neanderthal origin. Some habits and characteristics have lingered along the evolution.
Many of them, like the risk for diseases, sneezing after eating dark chocolate or the keratin production in the body have continued to be part of our systems. All researchers were wondering where the Neanderthals genes disappeared. After conducting some studies, they have unveiled that answer bears in the populations which got to be the product of Neanderthals and modern humans’ breeding.
Scientists have also revealed that the natural selection is less present in small populations. Graham Coop, who is a genetics professor at the University of California, Davis, has argued that Neanderthals registered to have had a decreased number of individuals because they had lived in severe weather conditions for hundreds of thousands of years.
Thus, Neanderthals managed to mate a lot more than modern humans. Therefore, they have collected more mutations which brought side effects, like an increased risk of diseases. This mutation could not prevent them from mating, transmitting the genes along. Ivan Juric, who is a geneticist at 23andme and he is also a co-author of the study, has claimed that after modern humans and Neanderthals started breeding, natural selection present in modern humans’ population has begun erasing those mutations.
In this way, the Neanderthals gene managed to vanish in time. In 2014, a team of researchers led by David Reich, who is a genetics professor at Harvard, have discovered that the DNA coming from Neanderthals was now located at great distance from significant genes from our genome. Therefore, this proved that natural selection was purging Neanderthals genes. They have excluded any other explanation, proving that infertility in Neanderthals was precluded.
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