Posted on 02/27/2026 7:02:08 PM PST by nickcarraway
New genetic research is reshaping how scientists understand ancient relationships between early humans and Neanderthals. A study published in Science suggests that mating between Homo sapiens women and Neanderthal men occurred more often than the reverse, leaving a lasting mark on the human genome.
The finding helps explain a long-standing mystery in genetics. Modern humans carry small amounts of Neanderthal DNA across most of their genome, but almost none on the X chromosome. These gaps, known as Neanderthal deserts, puzzled scientists for years.
Modern humans and Neanderthals split from a shared ancestor about 600,000 years ago. Human ancestors evolved in Africa, while Neanderthals adapted to Eurasia. Over time, humans moved into Neanderthal regions, and the two groups interbred.
As a result, most people outside Africa today have about 2 percent Neanderthal DNA. Some African populations also carry smaller amounts through later migrations.
Why Homo sapiens women and Neanderthal pairings matter in DNA What stood out was where that DNA survived. Neanderthal genes appear widely on non-sex chromosomes but are scarce on the X chromosome. For years, researchers believed this happened because Neanderthal genes on the X chromosome harmed human health and were removed by natural selection.
The new study challenges that view by turning the comparison around. Researchers examined the genomes of three Neanderthals and looked for modern human DNA, especially on their X chromosomes. They compared these results with genomes from African populations that had no direct contact with Neanderthals.
The pattern was clear. Neanderthals carried far more modern human DNA on their X chromosomes than on other chromosomes. One analysis showed an excess of more than 60 percent. That result ruled out genetic incompatibility.
If Neanderthal genes were toxic, modern human genes should also be missing from Neanderthal X chromosomes. But they were not.
Sex-biased mating offers a simpler genetic explanation
Researchers concluded that mating patterns offer a simpler explanation. Because females have two X chromosomes and males have one, the direction of mating matters.
If Neanderthal men more often had children with homo sapiens women, fewer Neanderthal X chromosomes would enter the human gene pool. At the same time, more human X chromosomes would appear in Neanderthals.
Mathematical models showed that this sex-biased mating could produce the genetic patterns seen today. Other explanations, such as migration differences or complex selection pressures, remain possible but require more assumptions.
The study does not explain why these pairings were more common. Researchers say the data cannot yet show whose preferences drove the pattern. The team now plans to examine broader genetic clues to better understand social structure, movement, and gender roles in Neanderthal groups.
The results suggest that social behavior, not just survival, played a role in shaping human evolution.
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Ping
Women always prefer Neanderthal men. Didn’t you know that? I thought everybody knew that…;)
Toxic masculinity explains everything.
Chad gets the girls. Homo Sapiens get the Friend Zone.
I suspect much of it was brawn over free association.
Prehistoric mudsharks and coal burners?
So simple even a cave man can do it.
Hahahaha!!!!
No s***. In other breaking news, the sky is blue, water is wet, and the Pope is Catholic. Film at 11.
As a Physics major geek I gave up long ago, lol. I understand the laws of the universe. Some things cannot be fought.
Every guy that has ever been married to a beautiful woman for over 50 years already knows she didn’t marry us for our brain power.
I just tell them this:
You wanted to pass me over? Fine. Your kids aren’t getting the genes that gave me 165 IQ and three full-boat college scholarship offers. Go F yourselves.
That is not certain.
They still do, don’t they?
“But I can change him…”
In before the Al Green pics.
I read a theory that Neanderthal women were more likely to get preeclampsia, a dangerous disease of pregnancy.
It could be that modern woman - neanderthal man pairings were more likely to produce healthy babies with less maternal mortality and morbidity than the reverse pairing, rather than reflecting attraction or captivity.
And if the pairings happened often enough, people would recognize which were the healthier, and avoid the less healthy.
Ha ha ha ha! I think almost every guy I know has come to that conclusion at some point in his life!
For many of us, it is a puzzle…;)
Did they have a say in the matter?
Only the blondes.
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