[jyscao]

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.

[raducu]

> 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?

[avadodin]

Ancestral Neanderthal Y-DNA was completely replaced by an incursion of Sapiens Y-DNA long before they(/we?) went extinct, so your whole theory of "we ain’t hitting that" is not very convincing to say the least.

"DNA deserts" likely indicate spots where there were issues with hybrid viability and not some half-disguised fantasy.

[hulitu]

> don't understand why we are so against this hypothesis that male homo sapiens did not particularly like the female neanderthal

Maybe the documentary 101 sexual accidents might enlighten you.

> (I can clearly see why as any modern male would).

What is a "modern male" ?

[faangguyindia]

Y chromosome is passed as is (baring few mutations) and same is true for mtdna.

Autosomal region is what acquires most ancestral dna as it's the one which recombines.

[microgpt]

why no mitochondrial then?

[jyscao]

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.

[vintermann]

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.

[jjtheblunt]

> 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.

[jyscao]

Ok yes, you're right. Guess I meant to say: no humans today are descended from someone between a male sapenis-female Neanderthals hybrid.

[b112]

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?

(I genuinely wonder this now)