Humans : one species, infinite varieties

[Maciamo]

I am currently reading The History and Geography of Human Genes, by Cavalli-Sforza, Menozzi and Piazza. I would like to summarize here my views on "human races" based on this book and other readings.

Is there such a thing as "human races", and if so how many ?

Some people argue that there is only one human race there is full interfertility between humans. Scientifically speaking, this means that humans are a single species. The term "race" is ambiguous as it has been given different meanings by different people. Dogs are a single species, but divided in distinctive races. Humans are not so clearly divided because of more numerous interbreeding and mixing through migrations, invasions or colonisations. In other words "cross-breeds" have mostly replaced "pure breeds" among humans.

As Darwin said, human races "graduate into each others" and "are not sufficiently distinct to inhabit the same country without fusion".

Yet, there are undeniable physical differences between a Swede, a Saudi, a Congolese, a Japanese, and an aborigenal Australian. It is true that gradation exist between all of them, and if they don't, children born from intermarriages will create these gradations.

The spectrum of races

This is why I compare humanity to a spectrum of colours. There are potentially an infinity of colours, although our senses only allow us to distinguish a limited number (a few millions, I believe) with more or less accuracy. Yet the richest language's vocabulary has hardly a few hundreds words to describe colours, and not more than a dozen is used in daily usage. Everybody can distinguish red from blue or from yellow. But it is not always easy to decide whether a colour is orange or red. That is because we use just a few words to describe millions of variations. The same is true with humans. Every individual is physically different. Differences are caused by the genes, hormonal changes, the environment, climate, food, mode of living, relations to others, etc.

The only thing that matters when comparing human "races" are the genes. But as individuals from the same family already have different genes, it could be argued that there are as many "races" as their are individuals. This is highly impractical, and if we did this for everything, we wouldn't have enough words for every colour, every difference piece of furniture, or just anything that doesn't look alike to our eyes. Taxonomists have tried to classify variations of human genes into a small number of categories, but common classifications give anything between 3 and 60 or more races. It is clearly arbitrary and depends on the personal preference of taxonomists to "lump" or "split".

Conflicting theories

Further in the book we reach the history of the Homo Sapiens. There are currently two major models regarding the origin of modern humans. The origin of humans prior to Homo Erectus and Homo Sapiens was in Africa. About 1 million years ago, Homo Erectus moved out of Africa and colonised Eurasia. Homo Erectus then evolved into distinct groups of Homo Sapiens in Europe, East Asia, Indonesia and Africa. However, we know that most of the genes of all modern humans on Earth were inherited from the African Homo Sapiens (commonly known as "Cro-Magnon"), that re-colonised Eurasia about 100,000 years ago. But did they interbreed to some extent with the other Homo Sapiens that were living in Europe (the Homo sapiens neanderthalensis, aka Neanderthal) and Asia (the descendent of the Peking Man and Java Man) when they arrived. This is were paleoanthropologists disagree. Here are the two possible theories :

1) The African Homo Sapiens ("Cro-Magnon") completely replaced the other humans without interbreeding. So the physical differences between modern humans only appeared within the last 100,000 years (i.e. very fast in evolutionary terms).

2) The African Homo Sapiens ("Cro-Magnon") mixed, to some extent, with the other varieties of Homo Sapiens already living in Europe and Asia, but remained genetically dominant, inheriting only some characteristics of the subdued indigenes, explaining the major physiological differences between modern Caucasoid, Mongoloid, Negroid or Australian aborigenes.

I personally find the second theory more plausible for several reasons :

a) Interfertility existed between all those varieties of Homo Sapiens. According to the book, barring to interfertility takes over 1 million years of evolution in mammals (so prior to Homo Erectus' settlement in East Asia).

b) The Homo Sapiens from Africa lived from 5000 to 10,000 years side by side with Neanderthals in Europe, in a mosaic of thousands of tribes. Tribes from both groups kept moving around the continent, so they couldn't help but run into each others, for friendly trading or skirmishes, probably involving occasional rapes or kidnapping of women from other tribes.

c) History has taught us that interbreeding (even through rape or sexual slavery) usually happens when a stronger or more technologically advanced group of humans invades the territory of another, despite differences in language, culture and physical appearance. Here are a few examples :

- About 2000 years go, some Koreans moved to Southern Japan and interbred with Japan's indigenous Ainu, eventually merging into the modern Japanese. DNA tests showed that modern Japanese inherited about 2/3 of their genes from the Koreans and 1/3 from the Ainu.

- In India, the white-skinned Aryans invaded the subcontinent around 1500 BC and mixed with the dark-skinned Dravidians, despite the caste system that they originally created to separate the two ethnic groups (Aryans at the top of the scale and Dravidians at the bottom).

- More recently, the Europeans and Amerindians also intermingled, especially in Central and South America. And so did the Black slaves that the Europeans brought with them. In a country like Brazil, many people have European, African and Amerindian blood.

d) Features of modern Europeans, East Asians and Australian aborigenes were already present in the European, East Asian and Indonesian varieties of Home Sapiens, before the African Homo Sapiens arrived.

- The European Homo Sapiens (Neanderthal) had a prominent occipital bun, a more elongated skull, a prominent browridge, a retromolar space, a larger nose, bigger eyes, large round finger tips, heavier body built, and hairier than other Homo Sapiens. This is still true of modern Caucasians, although much less than Neanderthal. The occipital bun is almost only found among Europeans (the exception being the Australian aborigenes and South African bushmen, who supposedly descend from another "unique" Homo Sapiens). It also thought that Neanderthals were red-haired and had freckles (and thus also fair eyes), a clear sign of Europeanness.

- The East Asian Homo Sapiens showed distinctive facial flatness, large bizygomatic breadth (e.g. wide jaws), small frontal sinuses, peculiar nose-root morphology, shovel-shaped upper incisors, smaller developement or absence of third lower molars, etc. All of them are found in modern East Asians.

- The Indonesian Homo Sapiens (Ngandong) showed such resemblances with modern Australian aborigenes that it was first thought that it was their direct ancestors. However DNA test confirmed that Australian aborigenes are closer to the African Homo Sapiens too, without disproving that a small percentage of Ngandong genes is still present. Like other indigenous Homo Sapiens, Ngandong was genetically "absorbed" by the African Homo Sapiens, probably because this latter's better technology enabled them to reproduce faster.


e) The only argument for a complete replacement is that skull features in Homo Sapiens found after the disapperance of "pure" Neanderthals were much closer to the African Homo Sapiens than Neanderthal. This, however, does not disprove a minor gene flow from Neanderthal. I know from experience that a person with 1/8 of European blood (so, one great-grand-parent) and 7/8 of Japanese blood looks almost undistinguishable from people who are 100% Japanese. Yet that represents 12.5% of the genes. If the ratio of Neanderthal genes in modern Europeans was 1% or less (and 99% African Homo Sapiens), it is obvious that the skull shape or DNA would be almost undistinguishable from that of the African Homo Sapiens - especially after an additional 40,000 years of evolution. Yet I believe that even a small percentage of non-African Homo Sapiens genes is more likely than none at all.


Conclusion

There are as many human "races" as we find convenient to divide human groups into. Personally, I like to think of the three main groups (Australian aborigenes excluded), i.e. Caucasoid, Mongoloid and Negroid, as the 3 primary colours (Red, Yellow, Blue) from which all other colours are derived. I see variations between Caucasoids as variations of the same primary colour (e.g. Indigo, Navy blue, Royal blue, Azur, Cyan, Turquoise...). I would thus consider North African, Middle Eastern, Central Asian and South Asian people as derivative colours (e.g. green, purple, orange...), as they are genetically in between. Ethiopians would be the same colour as Negroid, but in a nuance closer to Caucasoid, because of their closer facial traits and genes.

[Maciamo]

I have created a separate topic for the evidence that Homo Sapiens interbred with Neanderthal in Europe.

[Bodin]

Interbreading has certainly hapened , only question is did descendants survived , and I believe they are .

[Bodin]

God egzample is settling of Turks in Anatolia , it was numerous but extended over centuries ( each generation would receive 1-2% of Turk genes) , so they genes are disapeared in masses of natives . Same could hapened with Neanderthal genes

[InukCanuck]

I am 1.5% Neanderthal. Why don't you guys participate in Geno 2.0?

[silkyslovanbojkovsky]

Interesting article, I mean the evidence does suggest that there was minor interbreeding in Europeans (1-4%). What is interesting to me is why there wasn't more interbreeding. I mean If they could fully reproduce that means they were all part of the same species. Indo Europeans definitely were a more dominant group than the native descendants of Cro-Magnons in Europeans, yet we know they still heavily mixed with them, and its still evident in the genetics of Europeans. Why wasn't it so pronounced between Cro-Magnons and Neanderthal? I think I have an explanation. Even in some of the Populations Maciamo listed, he left one thing out. the genetic mixing is more heavily pronounced on the subordinate people. They are the ones being raped or sexually abused, and the descendants of these relationships will end up being part of the subordinate social group. This is evident in The United States where African Americans(black americans) on average have about 30-35% European genes, where as European Americans(white americans) have 0-3% African genes. In the past in the U.S if someone was half black and half white he became a part of the African social group separate from the whites, thus mixing one racial group, while the other remained rather unmixed. I think this must have been the case with Neanderthals and African Homo-sapiens, the Neanderthals though not a different species were still very different from Cro-Magnons, they were obviously discriminated against, probably raped and abused, but shunning the mixed offspring into being a part of Neanderthal culture. Though im sure Asians and Europeans do have some traits from these people such has thicker brow ridges and being harrier, and Asians having more gracile bone structures and flatter faces. Im sure a lot of this has to do with climate and diet. Its obvious that Neanderthals became white because the lived in a northern climate, this could have happened to Cro-Magnons in the exact same way without having mixed with Neanderthal. Very interesting stuff, im surprised theres not more comments on this thread!

[Noman]

There was no doubt a big overlap of genes between the groups already, and many are rare, meaning you have 1-4% of rare genes that come from neanderthal. So you can't say that the amount of admixture was 1-4%, it would have to be much higher to account for that.

[silkyslovanbojkovsky]

There was no doubt a big overlap of genes between the groups already, and many are rare, meaning you have 1-4% of rare genes that come from neanderthal. So you can't say that the amount of admixture was 1-4%, it would have to be much higher to account for that.

To account for what? Physical traits? Im not sure if its over 4%, we will have to see what newer studies reveal. However, I do not believe that light hair,eyes, and skin could not have developed separately in humans with out contribution from Neanderthals. Its amazing my self how dark I am in the summer and how light I become in the winter. I don't believe that evolution always takes such a long time. For example blonde hair is also seen in people from Melenasia but developed seperataly from blonde hair in Europeans. They obviously do not have the same source as people in Europe for their blonde hair yet they have it! Maciamo speaks of how Siberian type people do not have light hair and eyes when compared to Europeans but they lived in Nordic climates. He uses this as some sort of proofe that Europeans received these traits from Neanderthal, but theres already been theories on why this is so, and one very strong argument of why they are darker is because they have always had a diet very rich in vitamin d from fish, where as Europeans did not. That has a drastic affect on the amount of melanin in the body. I am not apposed to the Idea that Humans do have genes from archaic populations but I am not over zealous either to just assume they had a big enough impact to affect physical traits, which has to be quite big to do that.

[Noman]

To account for what? Physical traits? Im not sure if its over 4%, we will have to see what newer studies reveal. However, I do not believe that light hair,eyes, and skin could not have developed separately in humans with out contribution from Neanderthals. Its amazing my self how dark I am in the summer and how light I become in the winter. I don't believe that evolution always takes such a long time. For example blonde hair is also seen in people from Melenasia but developed seperataly from blonde hair in Europeans. They obviously do not have the same source as people in Europe for their blonde hair yet they have it! Maciamo speaks of how Siberian type people do not have light hair and eyes when compared to Europeans but they lived in Nordic climates. He uses this as some sort of proofe that Europeans received these traits from Neanderthal, but theres already been theories on why this is so, and one very strong argument of why they are darker is because they have always had a diet very rich in vitamin d from fish, where as Europeans did not. That has a drastic affect on the amount of melanin in the body. I am not apposed to the Idea that Humans do have genes from archaic populations but I am not over zealous either to just assume they had a big enough impact to affect physical traits, which has to be quite big to do that.

Basically, 1-4% of traits in europe (now it's considered more like 8%) are things that don't exist in sub sahan africa and are individually rare.

Meaning maybe there's only 0.1% who have many of these genes but there's a LOT of these genes. There's actually more genetic diversity in europe than the whole rest of the world.

The previous theory was that farming made this happen through population expansion, but that doesn't hold water because the chinese got basically wiped out completely by the plague, and then rapidly expanded to the largest population in the world, and they show the exact opposite. They are homogenous to the extreme, almost like every chinese person is a cousin. Same goes for arabs, they are all highly inter-related.

There's also some studies to show a "population expansion" led to the addition of more "markers" in human population which coincides with the time modern looking humans start to show up in europe (in 30k BC in central europe). Obviously if you have any idea what you are talking about you realize that's not how a population expansion works, that's how introgression from other populations works (unfortunately there's a lot of bad studies) but the data itself is fantastic. So that means probably even more of these markers will be found to be introgressed from neanderthals and possibly even other as yet unknown ancient humans, and keep in mind they have only sequences 2 or maybe 3 neanderthals at this point.

So you expect the italian, french, spanish, etc. neanderthals to all add a little bit here and there, just like these populations are similar but a little different today. This is even more the case since back then travel is not going to be as fast so populations will be more distinct.

So the reason I say it has to be more than than a one time thing is this is a whole raft of genes, not like one clump some people have more or less of. To have this big of a variety means there's a whole ton of mixing that happened. There's more genes taken on by neanderthals in europeans than exist as differences between europeans and and other modern races in thr first place. If it were a one time event then anything that can be called a marker ie it's neutral or even a little deliterious, would have trickled out long ago, or at the very least it would all be clumped together instead of different people having different neanderthal genes, all rare. This could only be possible if the entire neanderthal population was subsumed over time by steadily more and more modern human migration.

[silkyslovanbojkovsky]

Basically, 1-4% of traits in europe (now it's considered more like 8%) are things that don't exist in sub sahan africa and are individually rare.

Meaning maybe there's only 0.1% who have many of these genes but there's a LOT of these genes. There's actually more genetic diversity in europe than the whole rest of the world.

The previous theory was that farming made this happen through population expansion, but that doesn't hold water because the chinese got basically wiped out completely by the plague, and then rapidly expanded to the largest population in the world, and they show the exact opposite. They are homogenous to the extreme, almost like every chinese person is a cousin. Same goes for arabs, they are all highly inter-related.

There's also some studies to show a "population expansion" led to the addition of more "markers" in human population which coincides with the time modern looking humans start to show up in europe (in 30k BC in central europe). Obviously if you have any idea what you are talking about you realize that's not how a population expansion works, that's how introgression from other populations works (unfortunately there's a lot of bad studies) but the data itself is fantastic. So that means probably even more of these markers will be found to be introgressed from neanderthals and possibly even other as yet unknown ancient humans, and keep in mind they have only sequences 2 or maybe 3 neanderthals at this point.

So you expect the italian, french, spanish, etc. neanderthals to all add a little bit here and there, just like these populations are similar but a little different today. This is even more the case since back then travel is not going to be as fast so populations will be more distinct.

So the reason I say it has to be more than than a one time thing is this is a whole raft of genes, not like one clump some people have more or less of. To have this big of a variety means there's a whole ton of mixing that happened. There's more genes taken on by neanderthals in europeans than exist as differences between europeans and and other modern races in thr first place. If it were a one time event then anything that can be called a marker ie it's neutral or even a little deliterious, would have trickled out long ago, or at the very least it would all be clumped together instead of different people having different neanderthal genes, all rare. This could only be possible if the entire neanderthal population was subsumed over time by steadily more and more modern human migration.

Do you have any sources to support what you are saying? Europeans are one of the least genetically diverse peoples in the world compared to Africans who are hugely genetically diverse. what study says Europeans have about 8 percent Neanderthal dna? I would like to read it. Like I said before I believe there was mixing but only to an extant.

[Noman]

Yeah, I have sources, hold on a few hours though, I will have to dredge them up.

The africans have more diversity to each other but paradoxically there's zero DNA in africa that doesn't exist elsewhere. They are also highly inbred in little groups. So they are COMPARITIVELY more diverse to neighboring tribes but their total gene variation count is negligible, and everyone outside of africa has all those variations, there's nothing new there basically. Or very close to nothing, anyway.

[LeBrok]

I don't believe that evolution always takes such a long time..

Ask yourself a question: What is easier, to interbreed with other hominids, who already have the proper skin gene for local climate (mater of one generation), or wait tens or hundred thousand years for the right mutation to accidently happen?

[Noman]

First off these are all rare DNA alleles. We could have inherited skin and eye color from neanderthals, too, but the neanderthal versions we found so far don't seem to exist in any current humans. So when I say more diversity I am not talking about shallow features but the whole number of genes in europe is much more than anywhere else.

http://dienekes.blogspot.com/2013/08...n-eurasia.html
Newer, highest estimates of neanderthal admixture.


http://johnhawks.net/weblog/mailbag/...fect-2013.html
Was it a one time thing? No. If so it would be more homogenous, basically neanderthal thoroughly interbred with outsiders to make humans of today.

http://johnhawks.net/weblog/reviews/...-africans.html
Touchs on accelerated evolution being due to neanderthals, and about mutation rate only working for random breeding fixed sized populations (ie useless).

http://johnhawks.net/weblog/topics/e...ends_2007.html
paper on acceleration. Now some acceleration is obviously true due to higher population levels.
This is talking about selection, too, not these rare alleles in common with neanderthals, however the time frame is right for some to be from neanderthals.

So you add these two things together and you get, for an expansion, a complete lack of neutral DNA addition. The selection parts will actually make things more homogenous, but rare and selected are oximorons.

But that's exactly what we do see in modern populations that came about 40k years ago or so. HUGE amounts of it:
http://www.eupedia.com/forum/threads...evealed-by-DNA

But it wasn't all rare stuff only a few people have today, some stuff in every living person comes from neanderthals, and some under heavy selection today did. Most of us got our speech center genes from neanderthals, and eventually everyone will have this more advanced version:
http://johnhawks.net/weblog/reviews/...tion-2008.html
At the time of publishing it wasn't known that neanderthals DID have this, here's where it came from.
So you can't claim they are less advanced as this was once seen as the smoking gun of human evolution, what made humans human. So at this point it begs the question, what introgressed into what?

I also looked for the homogenity of han chinese, black africans, and arabs, but I got tired of it. Suffice to say for arabs and black african tribes it's well documented (and always the case for small groups). For chinese they show much greater homogeniety on the denisovan and neanderthal alleles showing a founder effect from the population bottleneck of the plagues some time ago, and the rapid expansion. Look up founder effects and expansions and bottlenecks and you will be able to figure this out for yourself if you doubt it.

http://johnhawks.net/research/langer...ment-2012.html
Molecular clock based on bad assumptions, clock rate appears to be wrong.

http://johnhawks.net/taxonomy/term/510
The higher rate is based on west europe accelerated mutation, ie on all these rare alleles. Take them out and you need a slower one.
That's not his point but it's the obvious conclusion, and shows the clock rate is based on assumption of observed values and backsolving (and is therefore pointless).
And again this contradicts the previous info!

http://johnhawks.net/weblog/reviews/...view-2010.html
But it IS lower!!! So if it's lower where does all this stuff come from? Well it don't take a math genius to do some addition and subtraction.
It's a lot of rare alleles we used to think came from accelerated mutation but now realize should not come from it, instead selection on other genes should help wipe out neutral/deleterious markers. It's all introgression. So there's even more introgression than we thought.

Easiest way to determine how much neanderthal ancestry we have is amount of negative bloodtype in population which we are almost certain comes from neanderthals, and only neanderthals.
Since it's bound to be under somewhat negative selection then if a population has 15% negative bloodtype at least 15% of its founders were neanderthal!
In small populations the y-DNA and mtDNA will "drift" out and become homogenous very quickly.
So if humans were in bands of a thousand or less we expect to see homogenous y-DNA after not that long, especially if the initial influx was a few at a time.

And that makes perfect sense for the numbers we get on the other genes. 1-3% of neanderthal wouldn't make 1-3% of your genes come from neanderthal, it would take a higher percentage. And now that estimates are tipping to 8% then the proportion of parentage has to be even higher (and most genes were the same to start with so won't change).

[silkyslovanbojkovsky]

Ask yourself a question: What is easier, to interbreed with other hominids, who already have the proper skin gene for local climate (mater of one generation), or wait tens or hundred thousand years for the right mutation to accidently happen?

I don't think that is a good way to look at it, Cro-Magnons didn't come in to Europe, see Neanderthals, and think hey its easier to get those light features from them instead of waiting for it. there is also evidence that light eyes and hair are not that old. people in Melanesia certainly developed blonde hair separate from Europeans and certainly did not get it from Neanderthal, yet they have blond hair.

[silkyslovanbojkovsky]

First off these are all rare DNA alleles. We could have inherited skin and eye color from neanderthals, too, but the neanderthal versions we found so far don't seem to exist in any current humans. So when I say more diversity I am not talking about shallow features but the whole number of genes in europe is much more than anywhere else.

http://dienekes.blogspot.com/2013/08...n-eurasia.html
Newer, highest estimates of neanderthal admixture.


http://johnhawks.net/weblog/mailbag/...fect-2013.html
Was it a one time thing? No. If so it would be more homogenous, basically neanderthal thoroughly interbred with outsiders to make humans of today.

http://johnhawks.net/weblog/reviews/...-africans.html
Touchs on accelerated evolution being due to neanderthals, and about mutation rate only working for random breeding fixed sized populations (ie useless).

http://johnhawks.net/weblog/topics/e...ends_2007.html
paper on acceleration. Now some acceleration is obviously true due to higher population levels.
This is talking about selection, too, not these rare alleles in common with neanderthals, however the time frame is right for some to be from neanderthals.

So you add these two things together and you get, for an expansion, a complete lack of neutral DNA addition. The selection parts will actually make things more homogenous, but rare and selected are oximorons.

But that's exactly what we do see in modern populations that came about 40k years ago or so. HUGE amounts of it:
http://www.eupedia.com/forum/threads...evealed-by-DNA

But it wasn't all rare stuff only a few people have today, some stuff in every living person comes from neanderthals, and some under heavy selection today did. Most of us got our speech center genes from neanderthals, and eventually everyone will have this more advanced version:
http://johnhawks.net/weblog/reviews/...tion-2008.html
At the time of publishing it wasn't known that neanderthals DID have this, here's where it came from.
So you can't claim they are less advanced as this was once seen as the smoking gun of human evolution, what made humans human. So at this point it begs the question, what introgressed into what?

I also looked for the homogenity of han chinese, black africans, and arabs, but I got tired of it. Suffice to say for arabs and black african tribes it's well documented (and always the case for small groups). For chinese they show much greater homogeniety on the denisovan and neanderthal alleles showing a founder effect from the population bottleneck of the plagues some time ago, and the rapid expansion. Look up founder effects and expansions and bottlenecks and you will be able to figure this out for yourself if you doubt it.

http://johnhawks.net/research/langer...ment-2012.html
Molecular clock based on bad assumptions, clock rate appears to be wrong.

http://johnhawks.net/taxonomy/term/510
The higher rate is based on west europe accelerated mutation, ie on all these rare alleles. Take them out and you need a slower one.
That's not his point but it's the obvious conclusion, and shows the clock rate is based on assumption of observed values and backsolving (and is therefore pointless).
And again this contradicts the previous info!

http://johnhawks.net/weblog/reviews/...view-2010.html
But it IS lower!!! So if it's lower where does all this stuff come from? Well it don't take a math genius to do some addition and subtraction.
It's a lot of rare alleles we used to think came from accelerated mutation but now realize should not come from it, instead selection on other genes should help wipe out neutral/deleterious markers. It's all introgression. So there's even more introgression than we thought.

Easiest way to determine how much neanderthal ancestry we have is amount of negative bloodtype in population which we are almost certain comes from neanderthals, and only neanderthals.
Since it's bound to be under somewhat negative selection then if a population has 15% negative bloodtype at least 15% of its founders were neanderthal!
In small populations the y-DNA and mtDNA will "drift" out and become homogenous very quickly.
So if humans were in bands of a thousand or less we expect to see homogenous y-DNA after not that long, especially if the initial influx was a few at a time.

And that makes perfect sense for the numbers we get on the other genes. 1-3% of neanderthal wouldn't make 1-3% of your genes come from neanderthal, it would take a higher percentage. And now that estimates are tipping to 8% then the proportion of parentage has to be even higher (and most genes were the same to start with so won't change).

Almost all of these articles are just blogs of people, and not very informative. Also you are misquoting things somewhat. Its not more like 8 percent, even in the article it says 3.4-8 percent. You are taking the high number which to me shows me your a little over zealous to claim Neanderthal ancestry. Also, I think I was reading it from one of maciamos articles that certain west African populations show rare genes from other older archaic humans. I still don't believe that Europeans are the most genetically diverse group of humans, that doesn't make much sense.

[LeBrok]

people in Melanesia certainly developed blonde hair separate from Europeans .

They are an interesting case, although it looks like it affects kids only. Maybe they've picked it up from Denisovans? It might have been recessive and only survived in this secluded tribe?

Of course, mutations can and will happen, but it is still easier to pick it up if interbreeding is possible.

[silkyslovanbojkovsky]

They are an interesting case, although it looks like it affects kids only. Maybe they've picked it up from Denisovans? It might have been recessive and only survived in this secluded tribe?

Off course, mutations can and will happen, but it is still easier to pick it up if interbreeding is possible.

Easier is not a good word really in this case, its just one possibility compared to another, and it is very possible that europeans developed blonde hair and light eyes through a separate mutation, the Melanesians are proofe that this is possible . Also if all europeans carry Neanderthal dna, which they should if they mixed with them because Neanderthal was essentially located in all of Europe. Then why are southern Europeans darker than northern europeans? because they live in a hotter climate where the sun is stronger and their bodies need to produce more melanin. Severe climates certainly push the body into extreme circumstances and we know that this does have a definite effect on evolution. I think that with the lack of melanin in the body in Nordic countries, the enviormental pressure would be very conducive to promoting light hair and eyes. Im not saying this is what exactly happened, but im saying that it could be very likely that europeans developed this on their own with out it coming from Neanderthals

[Noman]

Almost all of these articles are just blogs of people, and not very informative. Also you are misquoting things somewhat. Its not more like 8 percent, even in the article it says 3.4-8 percent. You are taking the high number which to me shows me your a little over zealous to claim Neanderthal ancestry. Also, I think I was reading it from one of maciamos articles that certain west African populations show rare genes from other older archaic humans. I still don't believe that Europeans are the most genetically diverse group of humans, that doesn't make much sense.

Well you can think whatever you like, I guess. There was a specific blog I was looking for that showed the "acceleration" and then wondered where it came from but I got tired of searching for it that made things more clear. The guy whose blog I linked to is the top expert when it comes to the subject of acceleration so there's no better source, and there was plenty of info there to understand the concepts but you just ignored it obviously, since you did not refute any real point.

The short of it is it doesn't take a math genius to figure out you need the percentage of ancestry contributed by a source to be higher than the percentage of that ancestor you actually have, especially for rare alleles. So believe whatever you like but it's wrong.

[silkyslovanbojkovsky]

Well you can think whatever you like, I guess. There was a specific blog I was looking for that showed the "acceleration" and then wondered where it came from but I got tired of searching for it that made things more clear. The guy whose blog I linked to is the top expert when it comes to the subject of acceleration so there's no better source, and there was plenty of info there to understand the concepts but you just ignored it obviously, since you did not refute any real point.

The short of it is it doesn't take a math genius to figure out you need the percentage of ancestry contributed by a source to be higher than the percentage of that ancestor you actually have, especially for rare alleles. So believe whatever you like but it's wrong.

Im wrong that Europe is one of the least genetically diverse populations on earth? This is supported by almost every study. Its very funny that a guy who claims J2 doesn't correspond to greeks, is calling everybody else wrong. If you would actually read my statements you would see I never denied mixing between Neanderthals and Cro-Magnon. I don't agree with you because you twist facts and over exaggerate numbers.

[Noman]

Ok, fine then. Lets see YOUR data on autosomal diversity in europe that proves it's the least diverse and has fewer rare mutations. Good luck with that. I already told you 100% of that comes from comparison of y-DNA and mtDNA clades, which means nothing. Waste some of your own time to make your own case instead of wasting mine then failing to address any part of it.

I spent hours collecting some of that post's links and you obviously didn't read them and have no idea about any of the issues I am talking about.

I think it's telling the first thing you assume is that I have some agenda. Amazing as it might seem I just have an interest in archaeology and human origins and not a political agenda, though clearly that's not the case for most people here.

[LeBrok]

Easier is not a good word really in this case, its just one possibility compared to another, and it is very possible that europeans developed blonde hair and light eyes through a separate mutation,

Very well, as you wish. It is much more likely and faster to get already existing mutation from species who you can breed with, than develop spontaneous mutation. For spontaneous mutation you can wait from one generation to infinity. It doesn't really need to happen at all. You have to keep in mind that population way back was much smaller than today, therefore probability of this mutation was also much rarer. This is just a question of probabilities, and likelihood.

the Melanesians are proofe that this is possible

You just speculating, it's not a proof. It is possible that blond hair in their tribe was more common in the past, and now they are "regressing" to black hair. Who knows maybe in few generation their blond hair will be very rare or extinct. There is no need for blond hair in this climate, therefore this trait might be recessive. Anyway it exist only in kids. They might have just some melanin producing gene turned off till puberty. The mutant founder effect?

Also if all europeans carry Neanderthal dna, which they should if they mixed with them because Neanderthal was essentially located in all of Europe.

IIRC the Iceman from Alps had twice as much of Neanderthal genes than today's europeans. It means we are loosing original Neanderthal genes. Well, I guess genes mutated, and I think we have more Neanderthal's DNA but it is becoming unrecognizable after many mutations.

Then why are southern Europeans darker than northern europeans? because they live in a hotter climate where the sun is stronger and their bodies need to produce more melanin.

During Ice age climatic zones were pushed down south. It is logical then to see white Neanderthals around mediterranean.

Severe climates certainly push the body into extreme circumstances and we know that this does have a definite effect on evolution. I think that with the lack of melanin in the body in Nordic countries, the enviormental pressure would be very conducive to promoting light hair and eyes. Im not saying this is what exactly happened, but im saying that it could be very likely that europeans developed this on their own with out it coming from Neanderthals

There are few genes involved in it, not one, so it is obvious that Northern Europeans developed extra mutations for extra light skin. I'm just saying that Neandertals gave them a "kick start". They made possible for Africans to move North into Europe and Asia. Otherwise black Africans would have been dead in few generations in Moderate climates.

[silkyslovanbojkovsky]

Very well, as you wish. It is much more likely and faster to get already existing mutation from species who you can breed with, than develop spontaneous mutation. For spontaneous mutation you can wait from one generation to infinity. It doesn't really need to happen at all. You have to keep in mind that population way back was much smaller than today, therefore probability of this mutation was also much rarer. This is just a question of probabilities, and likelihood.


You just speculating, it's not a proof. It is possible that blond hair in their tribe was more common in the past, and now they are "regressing" to black hair. Who knows maybe in few generation their blond hair will be very rare or extinct. There is no need for blond hair in this climate, therefore this trait might be recessive. Anyway it exist only in kids. They might have just some melanin producing gene turned off till puberty. The mutant founder effect?



IIRC the Iceman from Alps had twice as much of Neanderthal genes than today's europeans. It means we are loosing original Neanderthal genes. Well, I guess genes mutated, and I think we have more Neanderthal's DNA but it is becoming unrecognizable after many mutations.

During Ice age climatic zones were pushed down south. It is logical then to see white Neanderthals around mediterranean.



There are few genes involved in it, not one, so it is obvious that Northern Europeans developed extra mutations for extra light skin. I'm just saying that Neandertals gave them a "kick start". They made possible for Africans to move North into Europe and Asia. Otherwise black Africans would have been dead in few generations in Moderate climates.

Look, I never denied anything you said. It is very possible what you are saying, but you are stating it as a 100 percent certain fact, which it is definitely not, it is just as much speculation. The fact that people in Melanesia have blonde hair, and even if it is in children(so what), is proofe that blonde hair can arise in a population with out influence from Neanderthals. That is not speculation. Also, of course it is faster to receive these genes from interbreeding, but that has no influence on peoples actions to mate! Cro-magnon wasn't thinking when he came into Europe "Hey those guys are lighter than I am which is better in this climate, I should breed with him so my children can have that." What I was saying is that southern Europeans are darker than northern Europeans yet both have Neanderthal dna, the fact that northern Europeans have lighter skin, eyes, and hair is because northern climates are conducive to these traits, I know you think that Neanderthal just kick started it, and Im not against this, im just stating another side of the coin. Neanderthal had these traits, and he certainly developed it on his own, why could this not happen again in a span of 40 thousand years. Of course this is all speculation. A lot of the threads, Maciamo's including, are just speculation. That's what intelligent people do is speculate. Also I do believe there was mixing but I don't think there is a HUGE amount of Neanderthal genes in Modern Europeans, because Modern Europeans very closely resemble Cro-Magnon much more than they do Neanderthal.

[silkyslovanbojkovsky]

Ok, fine then. Lets see YOUR data on autosomal diversity in europe that proves it's the least diverse and has fewer rare mutations. Good luck with that. I already told you 100% of that comes from comparison of y-DNA and mtDNA clades, which means nothing. Waste some of your own time to make your own case instead of wasting mine then failing to address any part of it.

I spent hours collecting some of that post's links and you obviously didn't read them and have no idea about any of the issues I am talking about.

I think it's telling the first thing you assume is that I have some agenda. Amazing as it might seem I just have an interest in archaeology and human origins and not a political agenda, though clearly that's not the case for most people here.

I didn't force you to do anything. If you spent hours doing something that's your own problem. Autosomal dna has proved even more that Europeans are the most homogenous continent on Earth, more so even then y-dna or mt-dna has. European countries cluster tightly to eachother compared to African clusters. Coming from a person who states that e1b was brought to Europe by Jews and J2 by the ottomans, Im not sure if you have any clue about genetics at all.