Mating between Neanderthals and the ancestors of Europeans and East Asians gave our forebears important evolutionary advantages but may have created a lot of sterile males, wiping out much of that primitive DNA, new genetic studies suggest."Our forebears"? I'm an African. I do not have European or East Asian ancestors. How do you write an article in a country in which there are people of various racial extractions and write "our forebears"? Oh right, you weren't thinking of the non-European descended masses.
“So it suggests that something came over from Neanderthals to present-day people that had to do with the skin and was advantageous and rose to high frequency.”"Present-day" what? Black people have the same skin they had when humans first appeared on the scene. So what "present-day people" are you talking about? And now onto other important matters:
The reports build on the publication in December of the full genome of Neanderthals that showed that they were genetically closer to modern Europeans and Asians than to modern Africans. The best explanation for that phenomenon was gene flow — a fancy term for interbreeding between the divergent species, which shared a common ancestor some 300,000 to 500,000 years ago.So let us understand exactly what is being said here: Europeans and Asians have bunch of genes in common with Neanderthals that African humans do not. And that 20% of Neanderthal genes are "introgressed", that is:
At least 20% of the Neanderthal genome "introgressed" into the genome of our European and Asian ancestors, and East Asians retained slightly more of it, according to Akey’s analysis, based on genomes from 379 Europeans and 286 East Asians.
The slightly larger Neanderthal footprint among East Asians is not easily explained without a second "pulse" of gene transfer after they parted from Europeans, Akey's study suggests. “It’s a two-night-stand theory now,” Akey said.
Infiltration of the genes of one species into the gene pool of another through repeated backcrossing of an interspecific hybrid with one of its parents.into the European and Asian populations and not the African. But remember: There is no such thing as race. Significantly:
“The 2% we see today is what’s remaining after there’s been some purging,” Sankararaman said. “We think that it was reduced by about a third.” That purge of Neanderthal DNA is “a huge amount in a relatively short period of time,” he said…No, doesn't meant it had any function but it doesn't mean that they did not either.
“It was established a couple years ago that there was a small but significant admixture with Neanderthals, but that doesn’t mean that the genes that were brought into modern humans had any function, that they were an improvement on what modern humans had," said Montgomery Slatkin, a UC Berkeley biologist who has done similar research on Neanderthal genetics but was not involved in either study. "But now there is convincing evidence that indeed some of them at least were selected in humans.”
Genes linked to several modern diseases were among the Neanderthal legacy, including those correlated to Type 2 diabetes. But how much of a risk we inherited is debatable — the diabetes gene likely helped us survive food shortages, and may have proved detrimental as food became all too abundant in recent time.Wait! such a minor amount of genes are linked to such a deadly disease? So the question is clear: What else are "linked" to relatively small numbers of genes?