What do you think happened to the Neanderthals?

Sea Sharp

I was reading an interesting article on the BBC website:

http://www.bbc.co.uk/news/science-environment-14673047

I've seen Neanderthals mentioned briefly in a few other threads but I think this subject deserves a thread of its own.

So now it's looking likely that interbreeding took place between humans and other hominids.

It's looking like modern humans are simply a breed of genus homo in the same way that Jack Russells and Labradors are breeds of dog.

Is it possible that the Neanderthal gene pool was simply diluted by modern human (50,000 years ago) immigrants, to the extent that the gene pool became 50% human, then 75% due to further dilution, over time?

This is in contrast to the idea that Neanderthals were killed off by modern humans, or that they failed to adapt to climate changes.

You could say that modern humans evolved to have 4% Neanderthal DNA. Alternatively you could say Neanderthals evolved to have 95% human DNA.

I'd imagine human DNA would have had an advantage when it came to sexual selection, given that we are led to believe that female Neanderthals were mingers:pac:.

Your thoughts?

Wibbs

Oh don't get me started. No really...

Sexual selection on gender may have been more along cultural lines. The Neandertal gene flow seems to have come from Neandertal men so far. They still haven't decoded the full genome and it's only from one/two Neanderta samples as I understand it, so they may not be representative.

Cultural/behaviour reasons? Even today women move around more. Men and men's DNA tends to stick more locally. You can even see that in rural areas in Ireland. Go to any town village in the west say and try and find single 28 year old women and single 28 year old men. Many more of the latter. One could also argue(and I defo would) that women are more variable and adaptable in mate choices than men. They have a much wider range of "jaysus I would" than men. Few men would turn down Scarlett Johanson, but gansie loads of women would happily turn up their nose at Brad Pitt, Geroge Clooney or any number of sex symbols one cares to mention. Johnnie Depp seems the only stable point(the bastard:)) and even then... I guarantee a woman reading this would say "meh, he's alright, but I prefer *insert unlikely weedy pop/film star here*. On a personal note this wonderful trait in the women of our species is the only reason I've ever had action.

Those choices may depend on environmental pressures too. IE(and very broadly speaking and outside of gender earning shifts) today in the west intellectual men are more successful and more valued than highly aggressive men. If society broke down the latter would become more attractive. Go back to paleolithic times and a Neandertal male might look damned attractive as an overall package depending on the environment. He would have needed way more calories to sustain himself because of his muscle mass, but he was able to sustain that through hunting skills. If a Homo Sapiens lady with much lower calorie needs hooked up with him she might be less vulnerable to hunger and so would their kids.

Defending her against other males? Pick the finest and strongest cage fighter/martial artist alive today and an average Neandertal bloke would rip his head off for sport. Mike Tyson, bear of a man and a very intelligent fighter(and man) at his best? If he sneezed in my general direction I'd need medical attention. He'd take one look at an adult Neandertal lad(a couple of whom reached 6ft) and think "ah here, WTF". Now Mick given the chap that he is, not afraid to dive in, would probably have a go and he may get a couple of shots in, but game over time. Ali? He'd likely say "floats like a butterfly, stings like a bee, but sod this I can run like a bloody cheetah when needs must".

Wild animals? These guys wrestled wild animals to the ground close in. Other than food items like mammoths and woolie rhinos and aurocs, they took on cave lions and cave bears FFS. The latter one of the biggest bears ever to grace our planet. I've a partial jawbone of one in my collection and the teeth are mad Ted. Make grizzly bears look like a large dog.

They may well have been very caring as a people too considering how many Neandertals found show serious injuries that they survived and could only do so by pretty heavy duty care by the rest of their family/tribal group. They also had pretty incredible immune systems to do so. Another advantage and it looks like that advantage was part of the genetic heritage they passed on to Europeans and Eurasians.

So to a Sapiens lassie, one of these guys may have been a very good bet. To a Sapiens bloke? Less so and not just the looks part. ON that score a fair few mn would get up on the crack in a plate so... If a Neandertal woman came into a Sapiens tribe she'd need more food right away. Culturally she may have wanted to be part of the hunting party and not up for "women's work" at the time. The first feminist. Given she would have been stronger than any of the Sapien blokes, not a lot of argument would have taken place.

A lot of hunter gatherer tribes today trade women. Very very rarely men and even then it would be young boys. The genetic heritage we have today might be that simple.

Of course the other possibility for the gender diff in the DNA might be forced. IE Neandertal men raping Sapien women. Makes for a good headline, but I don't buy it. 4% left(so far) is a lot of DNA after this length of time has passed for that IMHO. And if we look at modern south east Asian folks they have their own archaic DNA from the Denisovians and it's an even higher %.

W all have these people(and I do mean people) in our blood and "soul". Including African folks who appear to be left out of this mix a bit. Unfairly and wrongly in my humble. For a start we're all more "African" than any other group and anyway our African father and mothers would have done the dance with no pants with other archaic people before we ever left east Africa which gave rise to most of what we are.

Basically and IMHO we're a great big family with some bloody wonderful buggers on all branches of that great big family that made who we are today. NO matter who you are or where you are from or where you find yourself, we've all those folks to thank for being able to look in the mirror and say "I'm Human". And that's a pretty damned impressive thing t be able to say. No other species in the 4 billion years of this planet has come within an asses roar of being able to say that.

Fair warning. Told you not to get me started. :D

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darjeeling

Wibbs wrote: »

Oh don't get me started. No really...

Sexual selection on gender may have been more along cultural lines. The Neandertal gene flow seems to have come from Neandertal men so far. They still haven't decoded the full genome and it's only from one/two Neanderta samples as I understand it, so they may not be representative.

Cultural/behaviour reasons? Even today women move around more. Men and men's DNA tends to stick more locally. You can even see that in rural areas in Ireland. Go to any town village in the west say and try and find single 28 year old women and single 28 year old men. Many more of the latter. One could also argue(and I defo would) that women are more variable and adaptable in mate choices than men. They have a much wider range of "jaysus I would" than men. Few men would turn down Scarlett Johanson, but gansie loads of women would happily turn up their nose at Brad Pitt, Geroge Clooney or any number of sex symbols one cares to mention. Johnnie Depp seems the only stable point(the bastard:)) and even then... I guarantee a woman reading this would say "meh, he's alright, but I prefer *insert unlikely weedy pop/film star here*. On a personal note this wonderful trait in the women of our species is the only reason I've ever had action.

Those choices may depend on environmental pressures too. IE(and very broadly speaking and outside of gender earning shifts) today in the west intellectual men are more successful and more valued than highly aggressive men. If society broke down the latter would become more attractive. Go back to paleolithic times and a Neandertal male might look damned attractive as an overall package depending on the environment. He would have needed way more calories to sustain himself because of his muscle mass, but he was able to sustain that through hunting skills. If a Homo Sapiens lady with much lower calorie needs hooked up with him she might be less vulnerable to hunger and so would their kids.

Defending her against other males? Pick the finest and strongest cage fighter/martial artist alive today and an average Neandertal bloke would rip his head off for sport. Mike Tyson, bear of a man and a very intelligent fighter(and man) at his best? If he sneezed in my general direction I'd need medical attention. He'd take one look at an adult Neandertal lad(a couple of whom reached 6ft) and think "ah here, WTF". Now Mick given the chap that he is, not afraid to dive in, would probably have a go and he may get a couple of shots in, but game over time. Ali? He'd likely say "floats like a butterfly, stings like a bee, but sod this I can run like a bloody cheetah when needs must".

Wild animals? These guys wrestled wild animals to the ground close in. Other than food items like mammoths and woolie rhinos and aurocs, they took on cave lions and cave bears FFS. The latter one of the biggest bears ever to grace our planet. I've a partial jawbone of one in my collection and the teeth are mad Ted. Make grizzly bears look like a large dog.

They may well have been very caring as a people too considering how many Neandertals found show serious injuries that they survived and could only do so by pretty heavy duty care by the rest of their family/tribal group. They also had pretty incredible immune systems to do so. Another advantage and it looks like that advantage was part of the genetic heritage they passed on to Europeans and Eurasians.

So to a Sapiens lassie, one of these guys may have been a very good bet. To a Sapiens bloke? Less so and not just the looks part. ON that score a fair few mn would get up on the crack in a plate so... If a Neandertal woman came into a Sapiens tribe she'd need more food right away. Culturally she may have wanted to be part of the hunting party and not up for "women's work" at the time. The first feminist. Given she would have been stronger than any of the Sapien blokes, not a lot of argument would have taken place.

A lot of hunter gatherer tribes today trade women. Very very rarely men and even then it would be young boys. The genetic heritage we have today might be that simple.

Of course the other possibility for the gender diff in the DNA might be forced. IE Neandertal men raping Sapien women. Makes for a good headline, but I don't buy it. 4% left(so far) is a lot of DNA after this length of time has passed for that IMHO. And if we look at modern south east Asian folks they have their own archaic DNA from the Denisovians and it's an even higher %.

The gender imbalance idea doesn't fit with the data. We've never found one live person with Neanderthal mitochondrial DNA or a Neanderthal Y chromosome, so both the male- and female-specific Neanderthal genetic lineages have died out. If what had occurred was extensive interbreeding with highly sex-biased mating, this wouldn't be the case.

As a first approximation, before we had the first Neanderthal genome sequence, we reckoned that modern humans had 0% Neanderthal DNA. Now we've a full genome, that estimate has turned out not to be a bad one - the amount of Neanderthal DNA in modern non-African humans is under 5%.

We're only now getting to the stage of population genomics, where we can sequence the genomes of thousands of people. This should show us whether the modern human population has picked up genes from across the entire Neanderthal genome, with different modern populations harbouring different relics of quite divergent Neanderthal DNA, or alternatively if only a small fraction of the Neanderthal genome is represented in our genomes and that fraction is not very diverse and is consistent across all Eurasians. If we find the latter, that would support the idea that modern human-neanderthal mating was a rare event that occurred soon after our ancestors left Africa. If the former, then that would suggest that hybridisation took place over a longer period and a larger gographical range.

.

Wibbs

darjeeling wrote: »

The gender imbalance idea doesn't fit with the data. We've never found one live person with Neanderthal mitochondrial DNA or a Neanderthal Y chromosome, so both the male- and female-specific Neanderthal genetic lineages have died out. If what had occurred was extensive interbreeding with highly sex-biased mating, this wouldn't be the case.

The guys behind the study seem to be arguing it's more likely these genes cam from the males, not the other way around. Well like you point out no evidence of mtDNA from Neandertals has shown up, but it is in the nuclear it seems. If there was hanky panky going the other way to any degree you'd expect to get some indication from the mtDNA I'd have thought. More matings from archaic male-modern female seems to fit the bill for what they've discovered so far. There may well have been flow the other way, but not large enough to echo to today.

As a first approximation, before we had the first Neanderthal genome sequence, we reckoned that modern humans had 0% Neanderthal DNA. Now we've a full genome, that estimate has turned out not to be a bad one - the amount of Neanderthal DNA in modern non-African humans is under 5%.

They don't have anything like a full Neandertal genome for a start. It's a very patchy sequence and it's from just three (male IIRC) Croatian Neandertals. Other studies on the mTDNA (the stuff that there's a lot more of than nuclear)of these guys has suggested that they were living in much more isolated groups compared to moderns. So it would seem to me to be an incredible stroke of luck to get sequences from such a relatively isolated snapshot in genetics and time that represents all or most Neandertal DNA and how that ended up in some modern populations? My own hunch? I'll lay a bet now that if they get more Neandertal nuclear DNA across their geographical and temporal range, they'll show three somewhat distinct groups. Western European Neandertals, Levantine Neandertals and west Asian ones.

Secondly, the difference between 0% and 5% is actually a huge difference. The difference between the original estimate and this new data and what it may tell us is a major thing that 0-5% in raw figures doesn't begin to describe. It blows the hardline "pure" out of Africa replacement model up for a start. Some recent studies are suggesting that these archaic genes(inc Denisovans, which had an even bigger impact on east Asians) may have even given an advantage to some modern human populations. http://www.zmescience.com/medicine/genetic/human-mating-with-neanderthals-made-our-immune-system-stronger/

From the analysis, the scientists estimated that more than half of the genetic variants in one HLA gene in Europeans could be traced back to Neanderthal or Denisovan DNA. Asians owe up to 80%, and Papua New Guineans up to 95%.

The jury is still out, but it is interesting. Denisovan influence on Asian populations appears to be even more than Neandertal and that's from just one fingerbone.

We're only now getting to the stage of population genomics, where we can sequence the genomes of thousands of people. This should show us whether the modern human population has picked up genes from across the entire Neanderthal genome, with different modern populations harbouring different relics of quite divergent Neanderthal DNA, or alternatively if only a small fraction of the Neanderthal genome is represented in our genomes and that fraction is not very diverse and is consistent across all Eurasians. If we find the latter, that would support the idea that modern human-neanderthal mating was a rare event that occurred soon after our ancestors left Africa. If the former, then that would suggest that hybridisation took place over a longer period and a larger gographical range.

Yea there's is defo more to be discovered that's for sure. The lack of good archaic DNA over wider areas is a bit of a stumbling block though. Though going on the current stuff, it seems these matings happened early on, likely in the Levant were we and them hung out for a couple of 1000 years. If they had happened later on in Europe then Asians probably wouldn't have the markers as their ancestors had long left. Like I say though the Neandertal stuff is from a tiny sample in one location and time. If they ever get to sample and sequence a western European Neandertal, say a Spanish or French one we may well find more markers surviving in the modern European population. Could you try that without the Neandertal DNA? Or narrow down were to look? IE look at European, Asian and African folks and look for the tiny differences between them. Then apply "genetic clock" type deduction. Would those small areas be ones to concetrate on when trying to sequence archaic dna?

.

darjeeling

Wibbs wrote: »

The guys behind the study seem to be arguing it's more likely these genes cam from the males, not the other way around. Well like you point out no evidence of mtDNA from Neandertals has shown up, but it is in the nuclear it seems. If there was hanky panky going the other way to any degree you'd expect to get some indication from the mtDNA I'd have thought. More matings from archaic male-modern female seems to fit the bill for what they've discovered so far. There may well have been flow the other way, but not large enough to echo to today.

The evidence for male or female-mediated gene flow is very weak in comparison with other cases where it's been clearly demonstrated.

One of the most striking cases I can think of is in cattle in Africa, where indicine (humped) cattle were introduced after the Arab invasions. Because people chose to breed from the indicine bulls, indicine Y chromosomes have spread right across the continent, replacing the native taurine ones, whereas indicine mitochondria (that would be inherited from indicine cows) have not spread much at all. The nuclear genome, as we'd expect, is in between these extremes.

An example in humans is elevated levels of Norse Y chromosomes in some north west European / Atlantic populations, suggesting that Viking males made a disproportionately high genetic contribution.

I've not seen any similar evidence for Neanderthals.

Wibbs wrote: »

They don't have anything like a full Neandertal genome for a start. It's a very patchy sequence and it's from just three (male IIRC) Croatian Neandertals. Other studies on the mTDNA (the stuff that there's a lot more of than nuclear)of these guys has suggested that they were living in much more isolated groups compared to moderns.

All the mtDNA samples to date actually seem to show Neanderthals being relatively genetically homogeneous. Samples from as far apart as Spain and southern Siberia are not very diverse. However, the Denisovans turned out to be quite distinct from Neanderthals when comparing mitochondria, so there was evidently variation out there. Denisovans were closer to Neanderthals when the nuclear genome was sequenced, and many now consider the Denisovans to be akin to an eastern Neanderthal. [BTW the Neanderthal nuclear genome sequence has come from females as far as I know *]

Wibbs wrote: »

Secondly, the difference between 0% and 5% is actually a huge difference. The difference between the original estimate and this new data and what it may tell us is a major thing that 0-5% in raw figures doesn't begin to describe. It blows the hardline "pure" out of Africa replacement model up for a start.

It's unfortunate that the debate became marked by entrenched polarisation between the OOA and multiregional camps for a long time. It's useful to have alternative models, and generally one starts with simple cases - either pure replacement by modern humans from Africa or pure evolution from local populations. But it's a mistake to turn these models into dogma, and indeed as the evidence comes in, the models should and do get refined. That said, the current model is now much closer to the simple OOA model than the simple multiregional one.

edit:

* We don't have a Neanderthal Y chromosome sequence, but all modern human Y chromosomes genotyped (including African) date to a common ancestor around 60,000 years ago, and this ancestor must - given all else we know - be a modern human and not a Neanderthal.

Wibbs

darjeeling wrote: »

The evidence for male or female-mediated gene flow is very weak in comparison with other cases where it's been clearly demonstrated.

Oh yea it's weak but apparently more likely according to the bods who've been responsible for the findings on this. I'd add in another possible influence on the more male to female transmission*. Cultural showing up in the genetics. Females tend to move around more. You see this in modern populations, especially isolated ones. The Male lines in such populations tend to stay more geographically stable.

So how can you tell if Neadertals were similar. For a start going by the bones and stones they do seem to be quite low in population size and very "local" with it. What evidence there is of them or their goods moving big distances is scant. Their tools come from nearby sources. The odd example shows some greater distances involved but nothing like when we come along. Now it appears when we come along some trade might be happening, but it seems Neandertals were quite isolated from each other culturally. They shared a culture but not as much as we did and do. If there were meetups simple trade, long distant trade anyway wasn't on the cards on the evidence so far, but...

Reproductively it gets interesting. The Sidron Neandertals in Spain** had their MtDNA examined and where it gets interesting is in the gender diffs. The men all had the same mtDNA type(haplotype?) so their mothers were close relatives. They share a maternal bond. The women on the other hand have a wide range of different mtDNA. The men were bound by "blood" the women came from outside that. Maybe from a different kind of "trade" when different tribes met every so often. makes good sense as far as keeping the genes healthy. If this was their reproductive culture, it's not unlike some tribes today and if we did meet and weren't trying to bate the head off each other we may have traded women as part of that culture.

Now of course that goes both ways, we may have taken in their women as part of that deal. So why would I still think it's more neandertal male - sapien female surviving to today? One possibility is like I said above their calorie needs were much higher than ours. A pregnant Neandertal woman "eating for two" even more so. Ditto for suckling. We may not have been able to sustain such a mouth to feed as well as her own people. One of our women with them would not have this difficulty. It wouldnt have to be by much to have an effect either. Slightly higher mortality or slightly lower fertility in Neandertal woman-Sapien man matings would over time lowered the amount of DNA surviving in a Sapiens group.

All the mtDNA samples to date actually seem to show Neanderthals being relatively genetically homogeneous. Samples from as far apart as Spain and southern Siberia are not very diverse.

Well compared to other great apes, yea, but they're diverse enough. They're as diverse as all modern humans across the planet in distinct populations today. The feldhofer Neandertals, the Russian ones and the Croatian ones differ by 12 base pairs. That's much higher than modern Euroasians in the same area(and even further east in Asia). Diversity wise they're more similar(but slightly more diverse than) to modern Africans who have the largest genetic diversity of any modern humans. They've pretty much the range of all modern humans today so they do appear to be isolated enough as a people.

However, the Denisovans turned out to be quite distinct from Neanderthals when comparing mitochondria, so there was evidently variation out there. Denisovans were closer to Neanderthals when the nuclear genome was sequenced, and many now consider the Denisovans to be akin to an eastern Neanderthal.

Well I dunno. They were as different to Neandertals as we are to Neandertals which is a bit of a gap. If we draw a sub species line between them and us, then we have to draw a similar enough line between them and them so to speak.

They're an interesting bunch if this single woman is representative of her population. They're an old population of humans sharing an old ancestry with Neandertals but apart long enough to be different humans. Maybe they are eastern "Neandertals". Some are positing Erectus for these people. I'd disagree and I'd think another way.

I've mentioned this before in the Paleontology forum here. My take for a long while now? For me Erectus was the first "real" human. He was one of us. Leaves Africa 1.5 odd million years back and goes walkabout all over the world. These people continued to evolve locally wherever they settled. I call the result Erectus 2.0. In Europe we get (Heidelbergensis then) Neandertals. European Erectus 2.0. In Africa we get early Sapiens, African Erectus 2.0. in Asia... Well this has always been the sticking point for me. The accepted view is that Erectus 1.0 stays on in Asia doesn't do much, then dies out and we come in and replace them in the environment. That makes zero sense to me considering the huge wealth of environments and evolutionary pressures in Asia. Outside of Africa(which gave rise to much of who we are remember) Asia has the most environmental diversity on the planet. So I have believed for a long time that there was indeed an Asian Erectus 2.0 and IMHO these Denisovan folks are them, or a partial window into them. It explains their similarities too, but differences from their European Erectus 2.0. And from us.

Where it gets real interesting is where these folks dna shows up in people today. They're in the middle of nowhere, but their bloodline shows up far away all over south east Asia and most of all in people from Papua New Guinea. Those folks have up to 8% of their DNA from Denisovans(and Neandertals). I think this may show some interesting population dynamics. For a start it likely shows that Denisovans were pretty widespread as a group, and/or we moved into their areas deep inland on a migration and took their genes with us and they survive best of all in places like New Guinea because of the isolated island populations. Like the clarly African folks who are to be found on the Andaman islands far from home.

[BTW the Neanderthal nuclear genome sequence has come from females as far as I know *]

Ah right. I dunno where I got that idea. I read stuff and it lodges in the grey matter, but the same grey matter doesn't do "links or GTFO" :D

It's unfortunate that the debate became marked by entrenched polarisation between the OOA and multiregional camps for a long time. It's useful to have alternative models, and generally one starts with simple cases - either pure replacement by modern humans from Africa or pure evolution from local populations. But it's a mistake to turn these models into dogma, and indeed as the evidence comes in, the models should and do get refined. That said, the current model is now much closer to the simple OOA model than the simple multiregional one.

Oh I agree, but it makes our human story so much more interesting and that's with pretty small samples of archaic dna so far found. Can't wait to see more!

We don't have a Neanderthal Y chromosome sequence, but all modern human Y chromosomes genotyped (including African) date to a common ancestor around 60,000 years ago, and this ancestor must - given all else we know - be a modern human and not a Neanderthal.

True but again there may be more to the story than "African Adam" or African Evee. One outlier is Australias "Mungo man". He's a fully modern human and a very early African migrant right at the edge of the known world for our ancestors at 40,000 years ago. His mtDNA is quite different and quite a bit older. Modern native Aussies(and the rest of us) have a different mtDNA heritage. Mungo man is a fully modern human who isn't a descendant of African mtDNA Eve. That's a bit of a shocker. He also looks different to later and modern native Aussies. So for his line to make it Australia, one of the first to come out of Africa, his maternal line must have been present in some numbers(or one helluva fluke) in the migration from Africa, yet his died out and the others haven't and we've no evidence of his line surviving along that route in ancient DNA. My prediction? I'd be asking someone to look at the Denisovan mtDNA and compare it to Mungo mans. I'll put the price of a feed of beers down that it'll have similarities.



* Sorry I should have defined this more. When I say more male to female, I should have said more male to female surviving down to this day in us.

**an interesting group of people. It seems they were all laid down at the same time, possibly as a result of intertribal fighting, or predation as all show signs of defleshing for meat. So it gives a better and very rare snapshot of what may have been going on. By comparison most samples could come from thousands of years apart in the same place.


PS sorry for the length (said the bishop to the actress).

PPS bear in mind the only qualifications I have are on my driving licence so pinches of salt at the ready.

Sea Sharp

/whoosh. :pac:

It's unfortunate that the debate became marked by entrenched polarisation between the OOA and multiregional camps for a long time. It's useful to have alternative models, and generally one starts with simple cases - either pure replacement by modern humans from Africa or pure evolution from local populations. But it's a mistake to turn these models into dogma, and indeed as the evidence comes in, the models should and do get refined. That said, the current model is now much closer to the simple OOA model than the simple multiregional one.

This is an interesting area.
Out of curiosity, have they compared DNA of Neanderthals with DNA of human remains from 20,000 years ago.
The 0-5% similarity between us and Neanderthals looses significance if there is anywhere near as much evidence of evolution in the human gene pool over that time period. Are we absolutely sure that people at the time of Neanderthals were at least 95% similar to us?
Similarly, if human remains from 20,000 years ago show more traces of Neanderthal DNA, then that would imply that natural selection (over time) favored our genetics over theirs.
The fact that there are so many more hypothetical scenarios for the 'multiregional' model might explain why currently the OOA model is more accurate.

W all have these people(and I do mean people) in our blood and "soul".

That's important to note. Popular culture leads us to believe that Neanderthals were nothing more than muck-savage apes, but what would they be like if they were alive in the 21st century?
I'd imagine the differences would be subtle (other than the fact that they could effortlessly kill us in a fight), perhaps it'd be a case of:
"Neanderthals are notoriously terrible drivers"
"Neanderthals don't have a sense of humor"

Wibbs

Sea Sharp wrote: »

This is an interesting area.
Out of curiosity, have they compared DNA of Neanderthals with DNA of human remains from 20,000 years ago.
The 0-5% similarity between us and Neanderthals looses significance if there is anywhere near as much evidence of evolution in the human gene pool over that time period. Are we absolutely sure that people at the time of Neanderthals were at least 95% similar to us?
Similarly, if human remains from 20,000 years ago show more traces of Neanderthal DNA, then that would imply that natural selection (over time) favored our genetics over theirs.
The fact that there are so many more hypothetical scenarios for the 'multiregional' model might explain why currently the OOA model is more accurate.

Good point. Modern sapiens human genetic change has sped up over the last 10,000 or so years http://www.scientificamerican.com/article.cfm?id=culture-speeds-up-human-evolution. More than the preceding 100,000. A homo sapiens of 60,000 years ago was quite a different beast on the genetic level in a number of areas. Diet being one of the biggies. Older sapiens would be lactose and gluten intolerant for a start. While they did process and eat grains(even Neandertals did) those grains were much lower in gluten. Other changes involve sperm production which is an interesting one.

So yea there may well be something to what you're saying. That's why I suggested comparing Mungo mans mtDNA to Denisovans may throw up some interesting comparisons.

That's important to note. Popular culture leads us to believe that Neanderthals were nothing more than muck-savage apes, but what would they be like if they were alive in the 21st century?
I'd imagine the differences would be subtle (other than the fact that they could effortlessly kill us in a fight), perhaps it'd be a case of:
"Neanderthals are notoriously terrible drivers"
"Neanderthals don't have a sense of humor"

I dunno. I suspect they'd be behaviourally different to us, just as Cro Magnons at say 80,000 years ago might be. We look very "domesticated" in behaviour and I'd argue in physiology too. We're more neotonous for a start. Our physical features particularly facial features are more like juveniles of archaic humans. We've got highly reduced brow ridges in the male, less robust, smaller noses, thinner bones, shorter "snouts", smaller teeth. I'd compare older hominids to more like wolves and modern cultural humans as more like dogs. Same species near enough, but very different in look and behaviour. The facial features I noted above are very close to the differences between wolves and dogs.

So I strongly suspect a Neandertal brought to now in a time machine, would be very similar as a kid to any other kid, but when puberty hit the "adult" Neandertal would come out much more strongly. More aggressive, xenophobic, territorial and mobile than a modern human. In the same way you could easily enough have a wolf around the house/garden as a cub and would show little diffs to a alsation pup, but as they matured the adult comes out and problems would start(they've actually done experiments on this).

Of course if Neandertals had survived they wouldn't have stopped evolving either. There's good evidence they did when they were around. They became more gracile, more soft in the features. IE you'd see the diff btween a Neandertal from 200,000 years ago compared to one from 30,000 years ago. So if they survived it's likely they'd have continued on that vein and became more "domestic" themselves, or they'd have avoided a lot of that and stayed in the "wild" in smaller and smaller enclaves until they died out due to population drop. Which is kinda what happened. Happened with wolves and dogs too. Wolves are endangered all over the place, dogs are everywhere. So maybe that, not hunting strategy, or calorie needs or direct competition is what happened?



*inc older versions of us, we've dropped a lot of the earlier robustness in the last 40,000 years.

Wibbs

There's another cultural feature of them compared to us. Like I said they were much more "local" in their thinking. There's the odd piece of evidence of more distant contact but its very much an outlier. They had a home range/terrirory and stuck to it. Which is interesting, because they differ from the much earlier Homo Erectus who had serious wanderlust. leaving Africa and going all over the world. Just like us. Something in the Eurasian environment seems to have selected for staying put in Neandertals. What? Who knows. Maybe because they had become the apex predator and were for so long and food was plentiful, this wanderlust died off? Or because they had a higher calorie need wandering too far was counterproductive?

You can see this difference when we first leave Africa and live very close by to Neandertals in the middle east. We live in the same sort of caves in the same valley as neighbours. We eat more plant matter, but our tools at that stage are very similar and very little sign of our cultural art type stuff. So at this point we're more similar than not. But while they leave behind tools and food remains from within a few miles, we're leaving behind some stuff from sources 100 miles away.

When we again meet them later on in Europe these differences are there, but one interesting one changes. Like I said in the ME we stayed in the same kinda caves, but in Europe we don't. We make our homes near the tops of hills and valleys overlooking the environment, they stay down low in the valleys. Various notions have been put forward for this diff.

My theory? A couple of years back while walking through rural Spain I noticed one diff between Ireland and Spain. Villages in Spain(and italy and elsewhere in Europe) tend to be situated picturesquely on the tops of hills. In Ireland(and the UK) that's a lot less evident. We're more likely to site villages in river valleys. So I asked myself why. The obvious one is defence. But why do we not do similar? Because we've only been invaded a very few times. Once really en masse. Ditto with the Brits(and by the same norse feckers). Central Europe has had shifting borders and invasions for 1000s of years so a much less stable enivironment open to attack at any time.

So maybe they stayed low down because for so long they were the only ones in Europe and stayed close to water sources. We move uphill because we're the invaders and need a defensive capability against the locals, even if it means a less stable water supply? So while we were OK with each other in the ME(and shagged at that point according to the DNA), there was a very different dynamic in Europe and that's why no evidence so far of European hanky panky? That we were more active invaders and neighbours?

Tails142

They walk amongst us.

darjeeling

Wibbs wrote: »

They [Neanderthals] are as diverse as all modern humans across the planet in distinct populations today. The feldhofer Neandertals, the Russian ones and the Croatian ones differ by 12 base pairs. That's much higher than modern Euroasians in the same area(and even further east in Asia). Diversity wise they're more similar(but slightly more diverse than) to modern Africans who have the largest genetic diversity of any modern humans. They've pretty much the range of all modern humans today so they do appear to be isolated enough as a people.

I don't think this is what we've found. A tree of complete mitochondrial sequences from human, Neanderthal and Denisovan was published as part of the Denisovan mitochondrial paper (link).



The Neanderthals (blue) have a bit less than half the range of mtdna diversity seen in modern humans (grey), as measured by how far back towards the tree root the branches converge. This figure only includes whole mtdna genomes, hence only Neanderthals from Spain to the Caucasus. However, the paper comments:

Krause Nature 2010 wrote:

Note that two partial mtDNAs sequenced from Teshik Tash and Okladikov Cave in Central Asia fall together with the complete Neanderthal mtDNAs in phylogenies4 (not shown)

darjeeling wrote: »

many now consider the Denisovans to be akin to an eastern Neanderthal

Wibbs wrote: »

Well I dunno. They were as different to Neandertals as we are to Neandertals which is a bit of a gap. If we draw a sub species line between them and us, then we have to draw a similar enough line between them and them so to speak.

I think my comment needs expanding. We know that the common ancestor of Neanderthals and Denisovans separated from modern humans and moved out of Africa. Later on this new lineage split in Eurasia into eastern (Denisovan) and western (Neanderthal) populations. These two new linages therefore stand in the same relation to our own, hence the 'eastern Neanderthal' comment, which only really applies if we're taking a human-centric view.

darjeeling

Another new paper out a month ago in Science (original paper here, free-to-view summary here) estimated population numbers of Neanderthals and modern humans around the time that the latter replaced the former.

The scientists, at the Archaeology Dept in Cambridge, surveyed sites in south-western France dating from 55,000 to 35,000 years ago which could be classified as either Neanderthal or modern human. To calculate population estimates, they used numbers of sites, intensity of occupation (rates of accumulation of tools and food residues) and size of sites. They concluded that the arrival of modern humans swelled the population of this part of Europe by 10-fold, and argue that this was a major factor in pushing the Neanderthals to the margins.

.

Wibbs

It's a good theory, though I'd personally say more a good result. The result was there were more of us than them knocking about over time, but the why is where the puzzle lies. It might be a chicken and egg scenario. Which came first, the population growth as the advantage or the advantage which led to population growth?

Another finding/supposition of those researching theEl Sidrón group's genetics is they reckon that the birth interval was around 3 years, which is the same as modern hunter gatherers. So they were reproducing at the same rates as we were for a given population.

Secondly we met as peoples before we met again in Europe in the Middle East/Levant in one of the first modern human migrations. We co existed there for 1000's of years in similar numbers and in that case it was the Neandertals who continued to occupy caves after we had. It was our population that dropped.

So to me it's more likely that all things being equal we had the same population growth rates as a base number. Some other advantage occurred between the Levant and Europe when we encounter each other again. The above study is seeing the results of that advantage or advantages in the population data. It's not the reason.

darjeeling

Wibbs wrote: »

It's a good theory, though I'd personally say more a good result. The result was there were more of us than them knocking about over time, but the why is where the puzzle lies. It might be a chicken and egg scenario. Which came first, the population growth as the advantage or the advantage which led to population growth?

The reason I think it's significant is that it helps explain why modern humans in western Europe didn't acquire significantly more Neanderthal genes during the period that both populations jointly occupied the same area. If modern humans were present in much greater numbers than Neanderthals, then the effects of any inter-breeding would be greatly reduced. This could be why the presence of Neanderthal genes in modern Eurasian humans seems to have resulted mostly or wholly from earlier cohabitation in the Near East.

Wibbs

Yea great point D*. Another thing that would add to the Levant being where they got jiggy the most is although Europeans and Asians have neandertal DNA they apparently have slightly different kinds. Which you'd expect if the mix was early and as those modern populations went their separate ways you'd get mutations/drift? over time. Given they've only gotten just over half the Neandertal genome so far it'll be interesting to see if there are any more links to be discovered. And as you say with more and more modern DNA being read all over the world we may see some really fascinating glimpses into who we are and who we were.

The Denisovan angle may get interesting too. AFAIR they only sequenced one of the samples, the other is yet to be done. I'll lay a bet on a hunch now the second sample will be different and that difference will be a bit of a WTF? moment. Like I say just a hunch.

The best thing about all this stuff for me is that it killed both the boring pure out of Africa model and the equally boring pure multiregional model. The road to who we are today was way more complex and fascinating.







*I'm just dubious that this population size diff is seen as a reason for them dying out. If two competing species are in an area and one dies out you're going to see the population numbers shift anyway. It doesn't exactly tell you why.

swordofislam

Wibbs wrote: »

*I'm just dubious that this population size diff is seen as a reason for them dying out. If two competing species are in an area and one dies out you're going to see the population numbers shift anyway. It doesn't exactly tell you why.

I think that the highest number of Neanderthals that ever lived at one time was about 75,000 across the whole range which would mean about 50,000 as a total Neanderthal population for 'Europe'.
I don't know what the modern human population of Europe was 50,000 years ago but if (say 2000 years after modern humans came into Europe) there were 10 times as many modern humans in the Neanderthal range because there were 500,000 modern humans than the Neanderthals were just out-competed.

If on the other hand the modern human population was not much larger than the peak Neanderthal Population (implying that modern humans were not able to extract a greater carrying capacity from their environment) than perhaps the problem lay within Neanderthal life-ways themselves.

Certainly relative to post Great Leap Forward/ Upper Paleolithic Revolution modern humans Neanderthals were not adaptive. It is true that they were if anything less static culturally than pre Great Leap Forward 'Archaic Moderns' but they were not in competition with pre Great Leap Forward Homo Sapiens Sapiens.

Though I do see your broader point that it is reductionist to say that the Neanderthals dies out because their population was smaller; it is getting close to saying they dies out because they died out.

[EDIT]

In fact if the Neanderthals were massively outnumbered I think it supports the idea of Neanderthal assimilation. After all even if one is very unused to abstraction a spear thrower and sewn clothes can be seen and do not have to be imagined.

Wibbs

Actually one reason I reckon we "won" are dogs. They never had them, we did. We're the first human to make this leap. We domesticated the wolf. The only large predator we ever did domesticate. We tried with the cheetah, but you wouldn't have one wandering around your gaff sleeping on the couch*.

I've always been fascinated by the how of all this. After all a full grown grey wolf is all teeth, muscle, claws and attitude. And way too timid as a working dog. Funny enough I was looking through some old online books and found this http://books.google.com/books?id=eRNsbeKvuhEC&pg=PA14&dq=alexander+henry+dogs&client=firefox-a#v=onepage&q=alexander%20henry%20dogs&f=false Interesting stuff and an interesting insight to how this may have occurred. The Sioux nation had dogs, but the interesting bit is the relationships between those dogs and the great plains wolves beyond. The Sioux's dogs would form a loose grouping close in to the camp. Beyond that the wolves would also form a grouping and would come close to camp and interact and mate with the domestic dogs. Back and forth this would go. Evidence of this remains to this day. All black north American wolves carry a gene from domestic dogs. The line seems quite blurred.

In that above account they note that the Cree nations dogs look as much like wolves "the dogs are very like wolves in appearance and disposition and no doubt are a cross breed/ a great many of them acknowledge no particular master". Further and interesting in itself they note that these dogs were not much use as hunting companions. So maybe the hunting partner thing didn't initially drive the domestication like is normally believed? They do say they were pretty good watchdogs and would make one helluva racket with approaching strangers(maybe they served as warnings of Neandertals coming too close). That, not the hunting may have been the initial draw? Their other use was as pack animals funny enough. The Indian lads were also noted to destroy any that were too aggressive.

This interaction can still happen today http://www.newsminer.com/view/full_story/7804925/article-Juneau-residents-considered-black-wolf--Romeo--a--friend-- A story of a fully wild wolf that hang out with domestic dogs and their owners out for a ramble and didn't attack either. He even approached people's houses "He developed a huge crush on our female lab, Dakotah, and that's how he got his name," Jans said. "He would hang around our back door and sometimes be waiting in our yard. My wife Sherrie said, 'There's that Romeo wolf again.' The name stuck." he even played catch "He was fetching tennis balls with our dogs," Jans said. "And he had a high degree of recognition for people. But we realized that we were part of a problem and we didn't want to contribute to it, so we backed off."


Now the usual chronology for the domestication of the dog is set about 10-15000 years ago. I'd dispute that myself. Though here's one that pushes that back even more to http://www.msnbc.msn.com/id/27240370/ns/technology_and_science-science/t/worlds-first-dog-lived-years-ago-ate-big/#.TnS3DeC65e4 31,000 years ago which I'd defo buy into. Interestingly the article mentions a discovery of footprints in a cave. A childs and a dogs and the child appears to have been carrying a torch accompanied by the dog. His or her "pet"?

So at least 30,000 years ago these new humans show up with dogs(which would also tie in with the chronology). When we lived side by side with Neandertals in the Levant we didn't have dogs and everything seemed pretty equal. In Europe we did. It's the biggest difference that I can find between us. Climate change? Nope Neandertals had survived and thrived through far worse than we had. Hunting skill? Ditto. Toolkit? Comparable(we may have even nicked some of their ideas). Culture? They had some, indeed may have had more than us at one point. But dogs they had not.

Maybe they killed wolves on sight? For food, or as a competitor? Or maybe they were afraid of them? Even polar bears are afraid of wolves. Four Neandertals out hunting, come across four Sapiens. My money's on the Neandertal lads. Four Sapiens and 6 or 7 wolf/dogs? The odds go the other way.

Maybe we didn't kill wolves for some cultural religious reason?** Maybe we were more approachable and that approachability brought the canids and the hominids together for the first time and it grew from there. The Indian lads and their interactions may have been an echo of all that. Then this evolved into all the purposes we put dogs to throughout history. It was a good deal for them too. Their wild ancestors are far far smaller in number, yet walk through any park on a sunday morning and look at all the "wolves" running around with full bellies and roofs over their heads.

TL;DR? The oul hound that licks your face is probably a huge part of why we're here and they're not.














*Though a mate of my dad's in Africa had a pet leopard. Raised it from a cub. Apparently it was a grand oul yoke. Very calm and friendly, had the run of the house.

**Though AFAIK no early european cave paintings show wolves, which in of itself is a strange omission?

Mahatma coat

on the Topic of Cave paintings not showing dogs, How are we certain that they are showing Sapiens? AFAIK the timeline for the cave paintings is around the same as the Final days of the Neanderthals

Mahatma coat

Eh Wibbs, you got any photos of these Toolkits of yours? ya know with the stone handaxe and other stuff? I'd love to see them

Wibbs

No worries MC, here ya go; The biface is pretty cool. There's a hollow in the flint that was selected for. For what reason who knows but it was defo selected for. It's very expertly fashioned, yet shows little sign of wear on the edges, but lots of wear on the main surface from handling. Also shows deep staining. IMHO from contact with leather. The point1 is a work of art in the hand. Serious workmanship(with some later losses on the bottom edge) and the biggest Levallois point I've yet seen. The scraper is another interesting one as the white inclusion seems to have been selected for and knapped around in a symmetrical way(no wear to the edges either). IMvHO they may be more cultural objects than practical. The blade is dictionary definition Levallois technique. You can even see where the original maker struck off the flake. 50,000 years ago. You kinda need to handle them in the flesh TBH. Pics don't really do them justice.

swordofislam

Heard another overtaking theory from Horizon the BBC program. Horizon Neanderthal claimed that the Neandethals were forest adapted and that our Savannah adapted bodies translated to the Steppe so that we could run down prey better.
I like it because I think it works nicely with the pattern of migration in Israel : Cold periods forested Northern Euopean Style Israel and hot periods grassland Israel BUT

One of the points that they make (John Shea says it in this documentary which surprised me) is that the Neanderthal's COULDN'T have thrown their spears. But even if we accept that we modern humans couldn't have thrown those spears that DOESN'T mean that an adult Neanderthal couldn't have. John Shea is a big guy but he is no Neanderthal.

Mahatma coat

yeah I remember something about their physiology and the larger shoulder blade meaning they would have more difficulty raising their arms over their head to throw a spear like we do, but that dosent mean that they didnt have a different throwing technique, I knew a bloke called Horse Nolan who could throw darts under arm with reasonable accuracy

Mahatma coat

saw this in YLYL2



:D:D

swordofislam

Neanderthals were very thin on the ground.
Neanderthals had smaller home ranges than HSS.
Neanderthals lived in forests.
At the last glacial maximum forests shrank and the steppe increased in area.
HSS could cover more ground that Neanderthals and could survive with much less food.

If there were only 10% as many Neandethals as HSS than for 4% of European DNA to come from Neanderthals is indicative of assimilation not extermination.


The spears found in the Schoeningen deposit could be thrown and they were made by Ergaster not Neanderthal. The idea that Neanderthals couldn't use projectiles is contingent on them de evolving.

Wibbs

swordofislam wrote: »

The spears found in the Schoeningen deposit could be thrown and they were made by Ergaster not Neanderthal. The idea that Neanderthals couldn't use projectiles is contingent on them de evolving.

Exactly, though they were made by homo heidelbergensis* not ergaster, they were much earlier and African in origin. Heidelbergensis had the same shoulder articulation so if they could throw then Neandertals surely could.





*Personally I don't rate the homo heidelbergensis label, I'd call them early Neandertals

Mahatma coat

on the Subect of Spears

Consider the Maori of New eland, they caried quite large and effective wooden spears, these were however stabbing weapons, I asked a 'Bro' about this and his response was

The Maori's could never see the sense in throwing away a perfectly functional weapon

Wibbs

Good point and Neandertals spears appear to be stabbing spears, but throwing spears are built differently design wise to stabbing spears. Stabbing spears are thicker in cross section and don't tend to taper along their length, for strength. Throwing spears are more slender with smaller points and are more weighted towards the tip for better flight and the Heidelbergensis ones followed the throwing design to the letter. They were built like modern javelins.

recedite

Perhaps the reason neandertals and HSS seemed happier to co-exist in the middle east than in Europe was cultural, those in the levant were simply accustomed to each other. In contrast, the HSS arriving in more northern areas took on the role of invaders, and thus the xenophobic instinct was stimulated, on both sides.

Imagine you are a neandertal, living happily with a small group in a cave by a river somewhere in France. Then these foreign geeks arrive and start helping themselves to your food supply. Individually they are puny enough, but they live in a large tribal gangs, up on the hill in a fortified stockades (raths) and every time you go near the place these big fierce dogs rush out.....
The following year, there is another tribe of them on the next hill. You can see how the "bad blood" develops into a vendetta that lasts many generations.
Compare to the European arrival in North America and South America. In the south things settled down after the initial clash, and there was more mixing of the Spanish and Indian populations. In the North, an enmity developed such that the native Americans were pushed north and westward until they nearly died out, before "compassion" took over and they were given a few reserves to live on. I wonder if the average modern Yankee would have much more than 4% Native American Indian blood in him?

Before anyone says the Europeans had a massive technology advantage arriving in America...yes, but at other times an enmity has developed between peoples on more equal terms, resulting in one population replacing other. For example the Romans wiped out the Dacians and repopulated Romania with their own citizens (and renamed it), mainly to get at the goldmines.

You can't really get the whole story just looking at bones and stones, but its interesting to speculate.

Enkidu

Wibbs wrote: »

Actually one reason I reckon we "won" are dogs. They never had them, we did. We're the first human to make this leap. We domesticated the wolf. The only large predator we ever did domesticate. We tried with the cheetah, but you wouldn't have one wandering around your gaff sleeping on the couch*.

We tried with cheetahs! That's cool. I've just started reading up on it, thanks.

As for domestication, domesticating any animal has had huge effects on humanities history. For example the domestication of the horse is basically the main reason Indo-European spread. (We actually have genetic results showing that every domestic horse in the world is descended from one to five males who lived in the Indo-European homeland about 3,000 B.C.)

swordofislam

recedite wrote: »

You can't really get the whole story just looking at bones and stones, but its interesting to speculate.

You can take the marrow out of bones to get new information from DNA. In my opinion the genetic evidence is consistent with assimilation of Neanderthals into a population that could cover more ground per day and needed less food to live.

recedite

swordofislam wrote: »

could cover more ground per day

You mean when out hunting?
The most successful predators employ teamwork. The most potent team I could imagine,for hunting large prey, for the times, would be organised by HSS, with wolf-dogs tracking prey by scent, Homo species using sight. Closer to the actual kill, faster running HSS circles around the prey, forcing it towards a cliff or river, then sends in a few neandertal gladiators to kill the beast with close range spear thrusts. Once the big herds were gone, it would be very difficult for neandertals to survive using more traditional ambush techniques.

If a few neandertals were "retained" by HSS for specialist work, such as tracking or killing or whatever, it might explain a certain amount of inbreeding, even if the two subspecies were generally at war with each other.

This kind of thing we can't get from bone marrow. For example the fossil record could place both in the same area at roughly the same time, but we don't actually know how, or even whether they interacted much together.
On the other hand, maybe they got on really well with each other on a platonic level, but just didn't interbreed that much.

Wibbs

swordofislam wrote: »

You can take the marrow out of bones to get new information from DNA.

yea but only in horrendously rare cases and such cases may well not be, indeed probably aren't "average".

In my opinion the genetic evidence is consistent with assimilation of Neanderthals into a population that could cover more ground per day and needed less food to live.

Not in Europe it's not. The Neandertal DNA so far discovered in modern humans came from Levantine Neandertal/Sapien jiggy jiggy, not European Neandertals*. In the Levant they shared the area for a very long time. They used a near identical toolkit and likely hunting methods. While the ranges of Sapiens were wider, it was for tool resources, not so much food and even then the majority of tool resource material was just as local as the Neandertals.

Now we get onto the "they needed more food" angle. One I would put much store in myself, but thinking on this further I'm starting to question some aspects of it. Numero uno, while individual Sapiens would require less food, the usually larger groups of Sapiens would even that out. Wherever we go soon after megafauna extinctions tend to occur. This didn't happen with Neandertals, even with their higher calorie need. So IMHO the calorie difference doesnt quite pan out as much as it may appear. Food sources? Neandertals had much wider food ranges that was previously thought. Only recently it's been found they processed grains before we did. Some examples of long hand axes/bifaces show extensive digging wear so were likely used for digging seasonal tubers(and show up in preserved ecosystems where such tubers would be common). Adaptation to novel foods? Again Neandertals show such adaptations. A good example being the southern Italian group who faced with less megafauna sources switched to a diet very similar to Sapiens. Ditto for the ones in southern Spain who started to hunt/eat much more marine food sources inc seals and dolphins. It would be my revised take that the food angle as a cause, or even a small influence on their extinction has to be somewhat reduced if not discarded at times.

recedite wrote:

Perhaps the reason neandertals and HSS seemed happier to co-exist in the middle east than in Europe was cultural, those in the levant were simply accustomed to each other. In contrast, the HSS arriving in more northern areas took on the role of invaders, and thus the xenophobic instinct was stimulated, on both sides.

I reckon this more than anything is what happened. And would neatly explain the lack of European Neandertal DNA in moderns.





*Personally I'd put money the two Neandertal populations were different in culture, maybe even slightly different in appearance. The European stock appear to be more robust overall, with bigger brow ridges.