Before anyone jaunts too far down the road of literal survivorship bias, I'd like to point out that it'd be incredibly premature—or perhaps way too late—to speculate much on the social side of things.
Elsewhere I've seen some people making hay about exactly whose-males were with whose-females, and want to point out that it's normal for genes to cause asymmetries.
In particular, consider the modern problem of RH incompatibility [0], where one pairing is more likely to end up with a child than an identical but gender-bent one.
Boy it so tempting to come up with "just so" stories to explain this. And so frustrating that we will probably never be able to determine the answer. but still cool.
Presumably this hypothesis is meant to explain why there is this observed asymmetry in the type of Neanderthal DNA we find in modern human populations that contain them, which is entirely autosomal. With none in the mitochondrial form, which is exclusively passed down along the female line, and also none in the Y-chromosome form, which is exclusively passed down along the male line.
Without weighing on the validity of their hypothesis that one or both sides found the other“especially attractive”, an alternative mechanism that could explain why we only see Neanderthal autosomal DNA in modern humans could be that only the female offspring of male-Neanderthal and female-sapiens pairings were reproductively fertile. This is more commonly the case in interspecies hybrids, see Haldane’s rule.
> Without weighing on the validity of their hypothesis that one or both sides found the other“especially attractive”
I get that it's survivor bias and all, but modern racial preference also paints a clear picture, I don't understand why we are so against this hypothesis that male homo sapiens did not particularly like the female neanderthal (I can clearly see why as any modern male would).
We found neanderthal fossils with sapiens DNA (afir it was something like 7% so not sterile hybrids, but a few generations after the hybridisation).
I don't think we have ANY evidence for non viability of male sapiens + female neanderthal non-viability, we just don't like the fact that this viability proves the asymetri.
Perhaps because modern psyche loves to picture males as sexual brutes and women as these higher wonderful rosy elves and this "shocking" neanderthal(i.e. "beastly") preference goes strongly against this meme?
Why would it be so inconcievable that the male part of homo sapiens drove the sexual selection for the more "refined" features of the species and the preference for intelligence of women was not intrinsic but partially "forced" -- i.e. warbrides and all -- so it would make perfect sense that some homo sapiens women would be attracted to the physical strength cues of male neanderthals, just like... gasp... modern women are?
Because these hybrids would contain mtDNA from their human female line. Neanderthal mtDNA could only be passed down by Neanderthal females.
And because none of those are found in any modern human populations, we can conclude no humans today are descended from female Neanderthals. Though whether hybridized descendants from male-sapiens female-Neanderthal pairings never existed, or they did exist for some time then eventually went extinct, we cannot currently say with certainty.
Strictly speaking we don't know that. It may always turn up an extremely rare Y or mtdna variant which was thought to be extinct. Ötzi's mt like was thought to be extinct (Wikipedia page even still says so) but very recently a North African man took a full mtdna test and it turned out he had the same. That could happen with neanderthal variants too for all we know.
> we can conclude no humans today are descended from female Neanderthals.
that looks worded wrong, strictly speaking. if there's a male neanderthal ancestor, then he very likely has a neanderthal mom or grandma or ... great^N grandma for some N.
We don't know that. I cannot imagine we have a perfectly accurate mapping of all mDNA neanderthals had. All current mDNA could actually have been neanderthal at one point in history.
How would we know otherwise? With absolute accuracy?
We certainly don't have access to thousands upon thousands of samples. Do we?
If we all seem to have neanderthal DNA in us, then we're all the progeny of someone which, to a degree, preferred certain "cross-pollination" behaviours.
Certainly, there would have been no revulsion. And potentially, there would have been preference. So if so, well.. why wouldn't that preference continue in the line?
One reason for that might be the size of the baby homo sapiens scull/head upon birth. Bigger brain might have meant female Neanderthals couldn’t give birth to Homo Sapiens babies. Just a theory.
I always wondered if Neanderthals disappeared or if they melted in the general human population since it was quite possible their numbers were much smaller than Homo Sapiens.
I can’t believe people are being so flippant describing this story (“sex life”) when there’s a high probability that the differential is because neanderthal males were raping homo sapiens females. Neanderthals had much higher muscle mass and were much stronger than homo sapiens.
We don't know that, and we don't know that neanderthal males were more prone to rape than homo sapiens males. And it's weird to even apply the 21st century concept of rape to prehistoric societies.
However, if one happens to be a race science type, there’s a lot of profit that can be made telling suggestive “just so” stories about which homo sapiens genetic lines are allegedly tainted with a larger proportion of neanderthal genes, or however that’s supposed to work.
Elsewhere I've seen some people making hay about exactly whose-males were with whose-females, and want to point out that it's normal for genes to cause asymmetries.
In particular, consider the modern problem of RH incompatibility [0], where one pairing is more likely to end up with a child than an identical but gender-bent one.
[0] https://my.clevelandclinic.org/health/diseases/21053-rh-fact...
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