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King
02-18-2015, 12:00 AM
So I'm curious and wondering if anyone has come across any insider information about the haplogroups of the Neanderthals (I can't find anything specific about it). Or if you have a suspicion or any sort of hypothesis on which y & mtdna haplogroups originates from the Neanderthals. Your insight is highly appreciated.

Hector
02-18-2015, 05:03 PM
No Sapiens mtDNA and Y haplogroup originates from Neanderthal. This has been established more than 20 years ago. Neanderthals will have their own haplogroups but I doubt there are enough samples so far to sort them out yet.

Joe B
02-18-2015, 05:16 PM
No Sapiens mtDNA and Y haplogroup originates from Neanderthal. This has been established more than 20 years ago. Neanderthals will have their own haplogroups but I doubt there are enough samples so far to sort them out yet. I'm not disagreeing. What is the scenario for the Neanderthal atDNA that some of us may have?

DMXX
02-18-2015, 06:01 PM
^ One possibility I always held in mind was some sort of sporadic integration-elimination model. Isolated cases of Neanderthal individuals mating with post-OoA humans, with most (not all) of the hybrid children not producing progeny to pass down the Neanderthal uniparental markers for various reasons. This could include socio-cultural or developmental (deemed too "different" to be fully accepted into a community?) attributes.

There are only two possible generational pairings I can foresee working with the current Y-DNA and mtDNA data:
1) Neanderthal male and H.S.S. female -> hybrid female (end result = loss of Neanderthal Y-DNA, retained human mtDNA, ~50% Neanderthal auDNA)
2) Neanderthal female and H.S.S. male -> hybrid male, who mates with H.S.S. female (end result = maintained human Y-DNA, replacement of Neanderthal with human mtDNA in second generation, ~25% Neanderthal auDNA)

I am not an anthropologist and don't even have a layperson understanding of early human culture, so have no ideas regarding which scenario would be more applicable to our apparently randy ancestors. I've seen a lot of confidence online from various users that the mixing was H.S.S. male->Neanderthal female, but I do question the source of that conviction (Hollywood caveman stereotype?).

Hector
02-18-2015, 07:57 PM
The pattern of sex-biased mating can be deduced from the ratio of the Neanderthal portion on X chromosome and autosomes but since male hybrids are generally infertile this becomes inconclusive not to mention the likely scenario where Neanderthal genes on X experience higher negative selections. But children are generally raised by mothers so it is more likely Sapiens females and Neanderthal males not to mention the fact Neanderthals were probably far stronger than Sapiens. However if patriarchial societies were the norm then it could be Sapiens males and Neanderthal females as abducted females live in abductors' society. But I don't see Sapiens males abducting much stronger Neanderthal females.

Lank
02-20-2015, 12:23 AM
We have some Neanderthal mtDNA samples, they fall outside the range of modern variation:

http://i61.tinypic.com/2wd1wci.jpg

Tomenable
03-27-2016, 09:21 PM
We have some Neanderthal mtDNA samples

Do we have also Neanderthal Y-DNA samples?

rozenfeld
03-27-2016, 09:53 PM
Do we have also Neanderthal Y-DNA samples?

As far as I know - we don't have. There is only one good-quality Neanderthal genome(Altai Neanderthal) and it's from a woman.

Hairyman
03-28-2016, 09:50 AM
John Hawks recently... "Neandertal sex acts are beyond counting"
http://johnhawks.net/weblog/reviews/neandertals/neandertal-dna/neandertal-sex-acts-beyond-counting-2016.html

GailT
03-28-2016, 06:11 PM
John Hawks recently... "Neandertal sex acts are beyond counting"
http://johnhawks.net/weblog/reviews/neandertals/neandertal-dna/neandertal-sex-acts-beyond-counting-2016.html

Quoting from the John Hawks post:


Importantly, there is no sign that the population was ever much smaller than 10,000 effective individuals, and that puts a lower limit on the number of hybrids that must have been introduced into this population to account for the Neandertal ancestry of its descendants. If these ancestors mixed with Neandertals during the minimum of such a bottleneck, then the effective number of F1 hybrids responsible for this mixture may have been as small as 400.

I wonder if Hawks considered the geographic distribution of the effective population size? Is it plausible that the OoA population never had an effective population size less than 10,000? That seems unlikely, and we could be looking at a much smaller number of interbreeding events with the OoA population.

epoch
03-28-2016, 07:35 PM
I'm not disagreeing. What is the scenario for the Neanderthal atDNA that some of us may have?

There is a paper out on the El Sidron Neanderthals showing that the male lineages are all related but the females aren't. That means that marriages, relationships among Neanderthals were patrilocal. [1] That would mean anatomical modern human (AMH) females that would have married Neanderthals would settle with the Neanderthal tribes and Neanderthal women living with AMH men. That way Neanderthal wives to AMH men would introduce Neanderthal mtDNA. So this would only explain the absence of Neanderthal Y-DNA among modern humans.

However, there a number of papers out that suggest that male offspring of Archaic-AMH suffered fertility issues. [2][3] We know this principle as Haldane's Rule [4], which states that of hybrids of two species the heterogametic (one with two different sex genes) is infertile. See mules as example.

That leaves us only violent encounters and rape. Suppose in a war Neanderthal tribes overwhelm AMH tribes, kill the men and rape the women and leave them, only the female offspring of these women can reproduce. No Neanderthal Y-DNA, no Neanderthal mtDNA in that case. Mind you, it's just a private little theory. But Haldane's rule must have played a role here IMHO.

[1] http://www.pnas.org/content/108/1/250.full
[2] http://science.sciencemag.org/content/early/2016/03/16/science.aad9416
[3] http://www.nature.com/nature/journal/v507/n7492/full/nature12961.html
[4] https://en.wikipedia.org/wiki/Haldane's_rule

EDIT: Another possibility is that women were basically raided for. Assume AMH tribes losing a fight and losing their women to Neanderthals. Imagine revenge raids to take them back. It happened with Aboriginals.

EDIT2: Greg Cochran disagrees with this scenario and has this: https://westhunt.wordpress.com/2016/01/30/caught-in-the-act/#comment-75961

Megalophias
03-28-2016, 08:27 PM
There is a paper out on the El Sidron Neanderthals showing that the male lineages are all related but the females aren't. That means that marriages, relationships among Neanderthals were patrilocal.
That would mean that Neanderthals at El Sidron were patrilocal. That doesn't mean that Neanderthals at a completely different place and time and belonging to a different culture (wherever modern humans interbred with them, probably the Near East) were necessarily patrilocal.

Supposing that they *were* strictly patrilocal, MH women could still have willingly have married into Neanderthal tribes and then returned to their MH parent's tribe when they were widowed or what have you, bringing half-Neanderthal daughters with them. But there is in any case no reason to suppose that everyone concerned was strictly patrilocal all the time.

Selection is obviously a likely explanation as well - or plain old drift. How many Eurasian maternal lineages survive from that era? Two. Eurasian paternal lineages? Three. If the Neanderthal interbreeding happened before the big Upper Palaeolithic expansion then we'd expect their uniparental lineages to be lost. Even if after, could still easily be lost to mere chance.

epoch
03-29-2016, 06:02 AM
That would mean that Neanderthals at El Sidron were patrilocal. That doesn't mean that Neanderthals at a completely different place and time and belonging to a different culture (wherever modern humans interbred with them, probably the Near East) were necessarily patrilocal.

Supposing that they *were* strictly patrilocal, MH women could still have willingly have married into Neanderthal tribes and then returned to their MH parent's tribe when they were widowed or what have you, bringing half-Neanderthal daughters with them. But there is in any case no reason to suppose that everyone concerned was strictly patrilocal all the time.

Selection is obviously a likely explanation as well - or plain old drift. How many Eurasian maternal lineages survive from that era? Two. Eurasian paternal lineages? Three. If the Neanderthal interbreeding happened before the big Upper Palaeolithic expansion then we'd expect their uniparental lineages to be lost. Even if after, could still easily be lost to mere chance.

As I said, it is just a little pet theory to play around with. However, should selection or drift play a part in the removal of Neanderthal mtDNA one would expect to find it at least somewhere among Paleolithic samples. We just saw a large number published, all strictly MH.

This obviously doesn't do away with your theory, nor does it prove mine.

Megalophias
03-29-2016, 02:28 PM
As I said, it is just a little pet theory to play around with. However, should selection or drift play a part in the removal of Neanderthal mtDNA one would expect to find it at least somewhere among Paleolithic samples. We just saw a large number published, all strictly MH.

This obviously doesn't do away with your theory, nor does it prove mine.

Fair enough. So far though we have only one ancient mtDNA that isn't M or N, though, so not a good sampling of the early stuff that was lost to drift.

mr_y82
03-30-2016, 05:28 AM
...

...

Working off what you guys have said and what I have read and heard on documentaries... Obviously modern homo sapien society was dominant on the basis of a 10:1 advantage alone, so...

Neanderthal males mating with modern female (limitation proposed by documentary) = only female offspring fertile? (as is typical of hybrids) = she does not carry Y, and carries modern maternal haplogroup? = no preserved Neanderthal haplogroup....

No matter if it was rape, or migration, or whatever, this could explain the lack of haplogroups, yes?

mr_y82
03-30-2016, 02:49 PM
Quoting from the John Hawks post:


I wonder if Hawks considered the geographic distribution of the effective population size? Is it plausible that the OoA population never had an effective population size less than 10,000? That seems unlikely, and we could be looking at a much smaller number of interbreeding events with the OoA population.

hmm... Interesting.

epoch
03-30-2016, 03:03 PM
Working off what you guys have said and what I have read and heard on documentaries... Obviously modern homo sapien society was dominant on the basis of a 10:1 advantage alone, so...

Neanderthal males mating with modern female (limitation proposed by documentary) = only female offspring fertile? (as is typical of hybrids) = she does not carry Y, and carries modern maternal haplogroup? = no preserved Neanderthal haplogroup....

No matter if it was rape, or migration, or whatever, this could explain the lack of haplogroups, yes?

There is some circumstantial evidence of violence between MH and Neanderthals:
https://www.sciencedaily.com/releases/2009/07/090720163729.htm
https://www.theguardian.com/science/2009/may/17/neanderthals-cannibalism-anthropological-sciences-journal

But again, slight evidence for theory A does not necessarily disprove theory B and both mechanisms could be working alongside each other.

EDIT: In your explanation, if I understand it correctly, the key point is that Neanderthal males only mated with AMH women (As Greg Cochran once put it: Anatomically Modern in all the right places!). But why that one way traffic? Furthermore, it would suggest that AMH mtDNA would pop up in the late Neanderthal population.

mr_y82
03-31-2016, 03:25 AM
There is some circumstantial evidence of violence between MH and Neanderthals:
https://www.sciencedaily.com/releases/2009/07/090720163729.htm
https://www.theguardian.com/science/2009/may/17/neanderthals-cannibalism-anthropological-sciences-journal

But again, slight evidence for theory A does not necessarily disprove theory B and both mechanisms could be working alongside each other.

EDIT: In your explanation, if I understand it correctly, the key point is that Neanderthal males only mated with AMH women 1)(As Greg Cochran once put it: Anatomically Modern in all the right places!). 2) But why that one way traffic? Furthermore, 3) it would suggest that AMH mtDNA would pop up in the late Neanderthal population.

1) haha

2) good question...blind faith in someone I figured was much more knowledgeable than me? heh...

3) yes, it would...

Thanks for the links. Good stuff!

Edit: It's amazing how often people thing theories have to be mutually exclusive... the old "coastal route" versus "ice free corridor debate"... and then there's the Pacific possibility, for the peopling of the Americas. It's all very fascinating, complicated, and based on such a tiny amount of evidence. But why limit yourself to one option? Amazing. :)

epoch
03-31-2016, 08:14 AM
1) haha

2) good question...blind faith in someone I figured was much more knowledgeable than me? heh...

3) yes, it would...

Thanks for the links. Good stuff!

Edit: It's amazing how often people thing theories have to be mutually exclusive... the old "coastal route" versus "ice free corridor debate"... and then there's the Pacific possibility, for the peopling of the Americas. It's all very fascinating, complicated, and based on such a tiny amount of evidence. But why limit yourself to one option? Amazing. :)

The point is that the absence of both Y-DNA and mtDNA of non AHM origin among humans was once, only ten years ago, considered proof of the absence of admixture. So the point of all these pet theories is basically only to show it is conceivable to find Neanderthal admixture without any trace of Neanderthal uniparental markers.

Also funny to see that Svante Paabo originally set out to back up the proof they thought they had that no admixture occurred. They thought they had narrowed it down to only possible minuscule traces.
http://www2.readingeagle.com/article.aspx?id=125240

EDIT: The Cochran reference, from which came some of the links: https://westhunt.wordpress.com/2016/03/21/everybodys-doin-it/

mr_y82
04-01-2016, 02:11 PM
Thanks for the links epoch!

That makes sense (it all being theoretical)... I just assumed there was some biological reasoning behind the theory that it was Male Neanders and Female Moderns that produced offspring.

epoch
04-13-2016, 07:26 PM
At last, we now have El Sidron Neanderthal Y-DNA and it is not seen among modern people. There is a paper out on it that mentions Haldane's rule:


Polypeptides from several Y-chromosome genes act as male-specific minor histocompatibility (H-Y) antigens that can elicit a maternal immune response during gestation. Such effects could be important drivers of secondary recurrent miscarriages30 and might play a role in the fraternal birth order effect of male sexual orientation. Interestingly, all three genes with potentially functional missense differences between the Neandertal and modern humans sequences are H-Y genes, including KDM5D, the first H-Y gene characterized. It is tempting to speculate that some of these mutations might have led to genetic incompatibilities between modern humans and Neandertals and to the consequent loss of Neandertal Y chromosomes in modern human populations. Indeed, reduced fertility or viability of hybrid offspring with Neandertal Y chromosomes is fully consistent with Haldane’s rule, which states that “when in the [first generation] offspring of two different animal races one sex is absent, rare, or sterile, that sex is the [heterogametic] sex.”

http://www.cell.com/ajhg/fulltext/S0002-9297%2816%2930033-7

Greg Cochran still disagrees and has this: https://westhunt.wordpress.com/2016/04/08/the-1/


I keep hearing people argue that this means that mating between Neanderthal males and AMH females must have produced sterile males, or that matings between AMH men and Neanderthal women were all sterile, or whatever.

That is not necessarily the case. A slight disadvantage is all that would be required to totally eliminate Neanderthal Y-chromosomes or mtDNA