Beacon Transcript – A recent study sought to find out the fate of the Neanderthal genes as the humanoids seemed to have little if any traces in the modern man’s genetic code.
A study seeking to understand the disappearance was undertaken by a team of University of California Davis geneticists and was led by the UC Davis Department of Evolution and Ecology and the center for Population Biology professor, Graham Coop.
The study results were published on November 8 in the PLOS Genetics journal and seem to indicate that the reduced number of genes could be a consequence of the population mix.
According to the research, only a small number of Neanderthals have mixed with the much larger population of modern humans, and their genes seem to have suffered from the natural selection process.
The Neanderthal population was spread throughout Central Asia and Europe and originally split from humanity’s African ancestors more than 500,000 years ago. Archeological research revealed them to have developed quite a cultural tradition and civilization.
The fossils remnants discovered during digs also revealed enough traces and samples of DNA so as to be able to determine their genome and compare it to ours.
As the first modern humans left their African territories, they started spreading through the aforementioned geological areas and proceeded to interbreed with the Neanderthal population.
With the first such hybrid offspring being believed to have had an equal DNA mix between the modern and Neanderthal genes, their respective children could have proceeded to further mix up the gene pool.
However, only a small percent of the Neanderthal genes can now be found in the common East Asian ancestry, a little less than in the European descendant, and none at all in Africa.
One of the theories that tried to explain the disappearance suggested that the respective genome became incompatible and as such, the offspring were either infertile or failed to appear.
But the current research reached a different conclusion. According to their results, the Neanderthal genome did not become incompatible with the modern one but instead, it started being removed by natural selection.
As Coop went to explain, their findings are consistent with the idea that a small population of Neanderthals may have mixed with a larger modern human one.
As the population size of the modern humans was demonstrated to have been much larger, the smaller population’s inbreeding and genetic variants were more probable targets of the natural selection process.
Inbreeding amongst a smaller population leading way to a number of somewhat harmful, albeit common genetic variants.
By mixing them up with a larger genetic pool, these weaker genome variants started being weeded out as they could not measure up to the stronger, more varied human DNA sequences.
The study results also seem to confirm previous, similar theories and to confirm the fact that the reduced number of Neanderthal genes may be owned to their smaller population numbers.
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