Talk:Recent single-origin hypothesis

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About whether single origin is about homo or homo sapiens sapies: I can believe it has two meanings, or that the former meaning has been replaced by the second (which would be metaphorically fitting). I was sure I had heard "African Eve" in contexts about the ancestor of Java man and Peking man. But I searched "African Eve" in the Gale electronic bibliography of articles and couldn't find any use predating Wilson's mitochondrial DNA study. So now African Eve seems to mean only mitochondrial Eve. Perhaps the same fate befell "single origin." In any event, the refs for this article and the links to it from other wiki articles require that it talk about the Out-of-Africa or "replacement" model, which says Peking man and Neanderthal et al were supplanted, without interbreeding, by the descendants of recent African migrants. So it will need rewriting and probably splitting in two and changes to the links to it if "single origin" indeed refers to an African exodus of early homo. 168... 20:43 17 Jun 2003 (UTC)

From Science News, May 17, 2003 "Mark Stoneking of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, an advocate of this **single-origin model** of human evolution, nonetheless regards the new evidence with caution. He hasn't seen the report but worries that the Cro-Magnon DNA is contaminated. However, mitochondrial DNA analyses of living people align with the single-origin, or **out-of-Africa,** scenario, Stoneking says. "

"Adherents of the contrasting **multiregional-origin** theory..." 168... 21:15 17 Jun 2003 (UTC)

Here's the earliest reference I can find to "single origin." It's a news article written by a science journalist, which appeared in Science magazine in 1987, on the heels of Stoneking and Wilson's first evidence for a "mitochondrial Eve." Note that the usage of terms in this excerpt implies that if one applies "single origin" to the million-odd-year old exodus, one will be speaking about what many people nowadays call the multi-regional origin model--i.e. the very opposite of what most people nowadays seem to mean by "single origin."

"The first, termed the candelabra model by Harvard University's William Howells, proposes that ancestral populations--specifically, Homo erectus--throughout the Old World each independently evolved first to archaic Homo sapiens, then to fully modern humans. This model, which has also been called the Neandertal phase hypothesis, therefore envisages multiple origins of Homo sapiens sapiens, and no necessary migrations. One consequence would be that modern geographic populations would have very deep roots, having been separated from each other for a very long time, perhaps as much as a million years.

"The second, which Howells called the Noah's Ark model, envisages a geographically discrete origin, followed by migration throughout the rest of the Old World. In this model, populations of Archaic sapiens might be completely replaced by the newcomers. So, by contrast with the candelabra model, here we have a single origin and extensive migration. Moreover, modern geographic populations would have relatively shallow roots, having derived from a single source in relatively recent times. "

It seems "Noah's Ark" didn't stick and "Out-of-Africa" or "African Eve model" are what researhers use.168... 21:31 17 Jun 2003 (UTC)

Re: "(anatomically modern humans)...evolved in Africa about 250,000 years ago", can you cite a source for this, SLR? Nothing I've read gives a number like this. I think the only people who speculate on this number are the Out-of-Africanists, who base their guesses on DNA evidence. In my readings, I most often see the date of the exodus and the date of the emergence of the species alike reckoned as "100 to 200 000 years ago"; i.e. separate dates aren't attached to the era of the common ancestor and the African exodus. 168... 20:07 19 Jun 2003 (UTC)

It is just a number I got out of a textbook -- if you have better dating, yes please change it. I just think that we need some estimate/approximate date for the emergence of Homo sapiens. I'll check other sources, but like I said, if you know of some recent consensus among paleoanthropologists, please by all means put it in (but I would expect the date for the speciation and the date for the movement out of Africa to be different) Slrubenstein

"The age of the most recent common ancestor (MRCA) for mtDNA, on the basis of the maximum distance between two humans...is estimated to be 171,500 +/- 50,000 yr. We can also estimate the age of the MRCA for the youngest clade that contains both African and non-African sequences from the mean distance of all members of that clade to their common node as 52, 000 yr. **Because genetic divergence is expected to precede the divergence of populations, this date can be considered as the lower bound for an exodus from Africa. " From "Mitochondrial genome variation and the origin of modern humans" Ingman, Paabo and others, NATURE VOL 408 7 DECEMBER 2000

So actually, with respect to my earlier comment, actually there is some basis for distinguishing the dates of the migration and the evolution from the DNA data, and some people are trying to do so. I read this excerpt before but forgot about it.

The only place I know to look for consensus or controversy in news stories and encyclopedia articles, where I don't recall seening argument about when H sapiens evolved _in Africa_. I figure the multiregionalists don't often have cause to argue that particular point, b/c events in Africa aren't central to them. 168... 20:29 19 Jun 2003 (UTC)

I am sure you are right on this last place. I have misplaced my most recent textbooks; earlier ones date the emergence of Hs to the middle pleistocene but I am sure the date can be pushed further back. I also suspect that fossil evidence will suggest that Hs emerged before the MRCA. Well, every article is a work in progress. For what it is worth, though, I wanted to tell you that I think this is sha[ing into a very good article. I feel like you have been more respectful of my changes, and I appreciate that -- but I want to emphasize that I also value many of your own changes and additions. Slrubenstein

I appreciate your cooperativeness too, and am glad for the signs that we might be able to work together in the future without antagonism. That's certainly my hope. Also, just in your capacity as an anthropologist, I'm glad you approve of the shape the article is taking and of contributions I've made to it.

One point about consensus that may not need making, but which I wish I had: For the paragraph in question, of course, we only need the consensus of the Out-of-Africansts, b/c this paragraph is about their contention. That's why I felt quoting Paabo's words alone established at least something. I ended up characterizing the dates as the BBC and other news sources have done. 168... 21:01 19 Jun 2003 (UTC)

I'm glad to see you share my feelings about working together. I also think you are quite right that for dating, it is only a consensus among the Single Origin people that need concern us. In lieu of any other information, I think the change you made to the date (the rather broad range) is good -- appropriate and well-stated. I do not know if this article is the appropriate place for a more polemical discussion of evolution, but I do think it is important that readers understand that the issue iiat hand really is whether Homo sapiens evolved in only one place or many -- not whether we all share an ancestor, for no matter where H. sapiens evolved, as long as you go back far enough evolutionary theory argues that all human beings have a common ancestor (I mean, multi-regionalists too think we have a common ancestor, it is just that our common ancestor, they argue, was H. erectus or some other species), as indeed all living organisms are descended from a common ancestor. I think this claim is something most people do not understand, or have a hostile reaction to -- and so it is important to explain it clearly. But perhaps such a general explanation belongs in the evolution article, not here (I am just musing out loud, as it were). Anyway, for the moment I think it is a fine article, Slrubenstein

The only thing that concerns me right now is the statement about when the first homo species evolved. At the very least, it's vague, and it's been made vague in order to produce a statement all the debators would agree on. I'd rather it weren't so vague. But I worry that it's inaccurate or misleading. In particular I'm thinking of the austrolopithicenes, which go back many more millions of years (4 mya?), and which I assume are Homo. Also 8 mya sticks in my mind for when apes and humans are supposed to have diverged (probably a number I picked up a long time ago, which could be out of date even if my recollection is perfect), and although I know that homo isn't supposed to have been born at the instant, I noticed on wiki the assertion that some researchers have proposed including apes in Homo. I don't know how seriously to take the assertion, but to the extent there's controversy about what species count as Homo, I don't think we should create an impression there isn't one. Given the context of this article, I think it would better under such a circumstance to come up with a sentence that avoids the subject all together. Could you say what you had in mind when you wrote that everyone agrees that the origin of Homowas "more than two million years ago"? 168... 22:36 19 Jun 2003 (UTC)

Actually, I see now that at least some academics don't put australopithicenes in Homo, even though they are "hominids" (and they date the first Homo to around 2 mya, as you wrote). I didn't catch on to the homind/hominoid distinction until very recently.168... 23:05 19 Jun 2003 (UTC)

That's right. There are debates over the evolutionary line of descent, but obviously at some point back in time we have ancestors who are not of genus Homo -- the questions are, when, and what to call them. I don't have any books in front of me right now, but I think your 8 million figure refers to our divergence from gorillas; I think we diverged from chimps around 5 million years ago. That would be our last divergence from the line of any other living primate -- but that divergence does not necessarily mark the beginning of genus Homo. By definition, australopithecines are not genus Homo, they are genus Australopithecus.

I came up witht the "over 2,000,000" phrase because to my knowledge Homo habilus was the first species of genus Homo, and used to be dated to 2m BP, but that firgure keeps getting pushed back.

Given that we are providing a year for the out-migration, I think it is crucial to provide some similarly approximate year for the evolution of that species.

You are quite right that there is ongoing debate, but I think our phrasing right now is careful enough to be acceptable to most scholars. Perhaps what we need somewhere is a link to other articles, and an explanation that these dates and classifications are approximate and subject to some debate? Slrubenstein

The entry is shaping up well, people. Nice going! Just one comment to make at this stage (particularly as most of my attention is elsewhere at the moment) and that regards your comment that: given that we are providing a year for the out-migration, I think it is crucial to provide some similarly approximate year for the evolution of that species, SLR. I'm not so sure about that. The out-migration is a concrete event. It happened at a particular exact time. Given appropriate evidence (which may even exist somewhere and be discovered tommorow) we may be able to learn what that time was, perhaps to an accuracy of a few thousand years.

The metamorphis of early hominids into the genus Homo, however, was not a concrete event. In nature there is no such thing as a "genus", that's simply a very convenient but quite arbitrary descriptive category that we humans have taken to imposing on the world (because it helps us make sense of things). The out-migration event, in other words, happened in and close to Africa perhaps 200,000 years ago - but the genus-transformation event happened in the mind of researchers in London during 1896 and New York in 1953, and so on). (No particular significance to those dates and places here, just random examples.)

The "first creatures of genus Homo" then, is like "the smallest large town in the USA" or the "first real motor car" - within reason, you can draw the line anywhere you like. How big is a "large" town? How practical does a car have to be before it's a "real" one? Opinions vary. Indeed, as you know, a significant number of biologists (probably a minority but by no means a crackpot view) hold that the genus-transformation event has not happened at all - humans, in this view, belong to the same genus as the other great apes.

A few years ago, DNA-DNA hybridisation pioneer Charles Sibley and his co-workers made a valiant attempt to put the arbitrary species-genus-family-order distinctions we use on a firm scientific footing: they set particular levels of measured genetic difference: more than X% different = different family, less than X% = same family but different genus, and so on. Sibley did most of his work with birds (which are particularly well-studied and in most cases have genetic material conveniently available in existing collections). As I recall, at one stage if we applied the Sibley method to humans and chimps, we would have been flat out even regarding them as different species, let alone different genera!

Since then, new and improved genetic difference measurements have come along and the human-chimp DNA difference is now thought to be (from memory) more like 5% than (as was once thought) about 1%. (The jury is still out on this though, and research continues apace.) There has also been a good deal of criticism of the rather mindless numerical difference method of defining a species (or genus). Critics point out - quite rightly - that defining a genus by picking a number in advance and then melting DNA to see if it works out to more or less than 7.8% is every bit as arbitary as defining it by counting the number of toe bones or primary feathers or measuring the ratio between skull volume and estimated average body mass. Nevertheless, those studies were and continue to be enormously influential. The American Ornithologists Union, for example, has adopted the Sibley-Munroe taxonomy almost completely, as have several other major bodies, and even those who have chosen not to adopt it have been greatly influenced by it.

Having said all that, I am now going to contradict myself and say that we should try to date "the great leap forward" - the apparently rather sudden aquisition of vastly increased language (and thus cognition, cultural transmission, and survival) skills. That, for my money, is the cruical date to place alongside the out-migration event - and it is also (at least in many researchers' opinion) the one great difference between humans and non-humans. (Seems to me that if we are going to draw a line between genera, this is the best place to do it - but this last is purely my own opinion: I don't know if any of the experts share it or not.) Last I heard, the best guess date for the great leap forward was in the order of 125,000 years ago. Tannin

Tannin, I appreciate your point and fully understand it although I think we are talking about two different things. You are talking about the conceptual nature of our taxonomic categories -- a point 168 alluded to, to which I responded with a seggestion of a brief note and a link to other articles. It is true that genus and species are ideas based on statistical patterns (of gene frequencies or of osteological remains or of other criteria). But they still refer to concrete real things. Much of the evidence for migration is fossil remains, and these same fossil remains are used to reconstruct hominid/hominoid evolution.

(I think many theoretical disputes among physical anthropologists and zooligists has to do with what kind of data they rely on, fossil evidence or genetic evidence. Obviously both are important and with time I am sure scientists can work out models that fit both sorts of evidence. So I take your examples from genetics with some qualifications. But I also accept your larger point that the cutoff from one species to another is arbitrary. You are right that you can't say that a new species emerged in June 2003 -- but this doesn't mean that you can't give a date, it is just that the date must take the form of a range.)

I think some sort of date -- even if it is within a 100,000 year range -- is important because advocates of both the multiregional and the single origin models agree that we are all descended from a common African ancestor, but they disagree as to whether that common African ancestor was Homo sapiens, or of an earlier Hominoid species. To decide between these two theories it is not enough to have a date for migration, especially since there have been several migrations out of Africa. You also need a date for the evolution of Homo erectus and for Homo sapiens. I agree with you that these dates are necessarily not only approximate but must take the form of a range, given the statistical nature of that to which they refer. But to me, this does not mean that a date is inappropriate or impossible, it just means that the date will take a different form (viz. approximate and a range) than the date of a "concrete event." Slrubenstein

The Theory in its existance will never, outdo the ability of man to conclusivly adhear that he was placed on earth by some higher being, and all Evolution is in its context is a direct wall upon the thought of that being.

Yeah, whatever. Check your spelling dude, and sign your posts. -Ste|vertigo 21:28, 16 June 2006 (UTC)

Contents 1 Recent? 2 Help wanted on related article. 3 When did modern humans leave Africa? 4 due weight 5 direct quotes from some sources 6 Out of Africa but later breeding between human species 7 references

[edit] Recent?

Granted there is no controversy regarding some "single origin", but why the rename? -Ste|vertigo 21:27, 16 June 2006 (UTC)

the main name of this article should be single-origin hypothesis. Firstly because of lex parsimoniae and secondly because Lord Monboddo postulated this theory in 1789. i also agree with tannin above that we need to find more research that dates the great leap forward. the key thinking may be related to migration AND linguistic development. Anlace 17:37, 29 June 2006 (UTC)

"Recent" means that the most recent common ancestor of humans is postulated to be on the order of 100,000 years ago, not on the order of 1,000,000 years ago, as the multiregional hypothesis would predict. "Recent" doesn't refer to the hypothesis being formulated recently, although in fact it was; Lord Monboddo postulated a single origin, but not a single origin in this specific time period based on more recent fossil evidence. --JWB 20:25, 29 June 2006 (UTC)

(Fix typo in above post, for clarity: changed 'does' to 'doesn't' in "'Recent' doesn't refer to the hypothesis being formulated recently" -- Ec5618 20:32, 29 June 2006 (UTC))

i understand where the word "recent" derived. i just think it makes the title gratuitously long and misleads general readers who are not intimately conversant with this branch of knowledge. Anlace 20:36, 29 June 2006 (UTC)

Three points: ¹In any case, the intro should reflect the article's name. ²A redirect exists to help people looking for "single-origin hypothesis". ³Note also that while our article on fruitflies is titled "drosophila melanogaster", our article on dogs is titled "dog" (where laypersons would expect to find it), not "canis lupis". -- Ec5618 20:55, 29 June 2006 (UTC)

so now we have four valid arguments for changing the primary name of the article to Single-origin hypothesis:

• The authors to date havent even mentioned the article title in the intro. defacto proof that the word "recent" is not on the tip of the tongue of those working in this field
• Lex parsimoniae...shorter and simpler is better if the two are tied
• even though the lay reader may find the article, he or she has to figure out why the word recent is important. its just confusing to the lay reader.
• Lord Monboddo did derive the theory in 1789. he didnt need to see the fossil evidence. and so what if he didnt know the exact point of origin. the present name is an insult to Monboddo. Anlace 21:03, 29 June 2006 (UTC)

• Most theories of human origin back to Genesis and beyond have been monogenesis. Polygenism has been the exception. Merely saying a theory is monogenic says very little. Both the model described by this article and the competing so-called multiregional hypothesis are single-origin hypotheses that would fit Monboddo's definition. The timing and other details are the only differences. Mention of Monboddo should be removed from the article entirely, or specifically cited as irrelevant.
• "he or she has to figure out why the word recent is important. its just confusing to the lay reader." Figuring it out is exactly what is required for comprehension of the article's topic. Stating it prominently helps highlight this.
• "Single-origin hypothesis" is not even the most popular name for this concept. "Out of Africa" (model/hypothesis/theory) is. "Out of Africa" is not any clearer as an actual description, but it is memorable and the best-known title.
• "Recent replacement hypothesis" would be even more accurate and less misleading. Most accurate would be qualifying "replacement hypothesis" with the time frame or species involved, like "Homo sapiens total replacement model", "Total replacement of Homo erectus model", or "Middle Paleolithic replacement model", or "120-60ky replacement model". "Non-interbreeding model" or "Homo erectus dead-end model" would also clearly communicate the theory. I haven't looked up whether clearly communicating the article's topic in the title is a defined Wikipedia policy, but at the least it avoids confusion. --JWB 23:57, 1 July 2006 (UTC)

Why dont we just use Middle Paleolithic replacement model and everyone will be happy? Anlace 00:12, 2 July 2006 (UTC)

Sounds good to me! --JWB 05:16, 2 July 2006 (UTC)

Perhaps we can wait a day and see whether anyone else weighs in before making the change. thanks for your patient and constructive dialog JWB. regards Anlace 05:20, 2 July 2006 (UTC)

can anyone tell me what the percentages are of academics worldwide, who dispute the single migration out of Africa theory?I get the impression its on been onthe wain in the last few years, but id like to get an idea of how many experts whove spent years getting paid to look at the evidence believe which theory. Also, is it treated as spurious to continue and argue that humans evolved absolutely separately in various parts of the world (all my limited knowledge in this area comes from the bbc :}80.192.59.202 18:23, 21 October 2006 (UTC)

[edit] Help wanted on related article.

Hi

I am asking for the editors of this article to help me on Hofmeyr Skull.

Regards, Gary van der Merwe ^(Talk) 20:26, 12 January 2007 (UTC)

[edit] When did modern humans leave Africa?

I've seen estimates ranging anywhere from 110,000 years to 25,000 years agao. It seems like every year they keep moving the date forward. What's the mainstrea scientific consensus? Also did modern humans mate with neandertals or not. I thought they DNA sequenced a neandertal and proved their was no mating, but now we have people looking at skulls claiming to have proved that we did mate with neandertals. What's the mainstream scientific thought on that question?

the earliest emigration of H. sapiens was some 80 kya according to genetic evidence. Of course there were later waves of emigration; the latest one is taking place as we speak. so far, it looks as though H. sapens did not interbreed with the Neanderthals, but this isn't final. dab (𒁳) 09:20, 26 February 2007 (UTC)

[edit] due weight

the intro makes it sound as if judgement was still pending between single and multiregional origin, while in reality, the scales have tilted significantly in favour of single-origin since the 1990, due to previously unavailable genetic evidence. "multiregional origin" should be presented as a theory that used to be competing, but was rendered obsolete in the course of the 1990s. dab (𒁳) 09:20, 26 February 2007 (UTC)

[edit] direct quotes from some sources

feel free to add any of this futurebird 00:23, 8 March 2007 (UTC) :

In 1994 Marta Mirazon Lahr and Robert Foley wrote that, although not all would agree, evidence for a single recent origin is accumulating. They theorize that the pattern of diversity behavioural, linguistic, morphological and genetic may be interpreted as the result of dispersals, colonisation, differentiation and subsequent dispersals overlaid on former population ranges.^[1] A 1996 study of DNA sequences of Alu elements indicate that the observed virtual lack of sequence polymorphism is the signature of a recent single origin for modern humans, with general replacement of archaic populations.^[2] In 2006 Hua Liu, Franck Prugnolle, Andrea Manica, and François Balloux wrote that currently available genetic and archaeological evidence is generally interpreted as supportive of a recent single origin of modern humans in East Africa. However, this is where the near consensus on human settlement history ends, and considerable uncertainty clouds any more detailed aspect of human colonization history.^[3]

[edit] Out of Africa but later breeding between human species

I remeber reading about in some news article this year maby national geographic that recent genetic evidence from the partial sequencing of the Neanderthal gnome suggest that at some point after we moved out of Africa modern humans mated with Neanderthals. I saw no info about this in the article. I think it would deserve at least a mention. Does anyone have more information.Lonjers 05:50, 21 March 2007 (UTC)

The general consensus is that we just don't know. The overwhelming amount of DNA evidence supports a Recent Out of Africa model, but it should be noted that some European DNA looks like it came from Africa a lot longer ago than the 100,000 years ago that is usually given for moder human dispersal. There are two basic ways to interpret this, either the DNA that looks old is just an anomaly, and as we find out more about our genome we will be able to reconcile it with an exclusively recent out of Africa thesis, or there really was some reproduction between archaic humans and modern humans that has been passed down to some of us today. If the second is accepted, then it is usually considered to be an extremelly small contribution, because most of the evidence shows a recent African origin, and because all modern humans are very similar globally. Chris Stringer says that most [researchers] now espouse a version of the ‘out of Africa’ model, although there are differences of opinion over the complexity of the processes of origin and dispersal, and over the amount of mixing that might subsequently have occurred with archaic (non-modern) humans outside of Africa2,7. [1] If there were large amounts of archaic DNA in us, then we would all look very different to each other. By that I mean that archaic hominids were very different to modern humans, and were very different to each other in different parts of the world (Homo erectus was very different to Homo neanderthalensis for example). If there had been large gene transfer between modern humans and, say Neanderthals in Europe and Erectus in Asia, then modern Europeans would be more like Neanderthals and less like modern Asians. Clearly modern Asians are more like modern Europeans than either group is like any archaic species. This holds true for all modern humans from all parts of the world. We are all more anatomically and genetically similar to each other than any of us are to any archaic. If there was reproduction between Cro magnons and Neanderthals in Europe, then it might also mean reclassifying Neanderthals, currently the current classification is absed on an assumption of no gene transfer directly between the populations, hence they are different species, Homo sapiens and Homo neanderthalensis, if gene transfer due to sexual activity were shown, and it were shown that these interactions produced viable offspring (ie offspring that were fully functioning and could reproduce, often the offspring of different species, like a mule or liger are sterile) then the different populations would need to be considered the same species, ie we would be Homo sapiens sapiens and Neanderthals would be Homo sapiens neanderthalensis. Some classifications do actually consider Neanderthals to be a subspecies of Homo sapiens, though I don't think this is the consensus. As for the claim that part of the Neanderthal genome has been sequenced, I have not heared anything about this. Indeed I think it unlikely that genomic DNA from the species would have survived, genomic DNA is very long, and very complex, and is likelly to have degraded. DNA has been isolated from Neandethal mitochondria on several occasions, but this is very different from modern mitochndrial DNA, and seems to indicate that our common ancestor with Neanderthals was over 400,000 years ago. Of course mtDNS has it's limitations, it can only tell us about a specific lineage, and just because so far no Neanderthal mtDNA is at all close to any modern human mtDNA, this does not proove nor disproove anything. Though this does tend to support the position that modern humans have an exclusively recent African origin. There has been speculation that remains that seem to be "intermediate" between modern humans and Neanderthals indicate reproductive activity between the populations, but there appears to be no genetic evidence for this: It is, however, worthwhile to note that samples considered as anatomically “transitional” between modern humans and Neandertals, such as Vindija (Smith 1984; Wolpoff 1999) and Mladeč (Frayer 1986, Frayer 1992; Wolpoff 1999), analyzed here, fail to show any evidence of mtDNA admixture between the two groups.[2] I would be very interested to find out about work that has managed to extract and sequence Neanderthal genomic DNA if you can remember the source. Cheers. Alun 12:01, 17 March 2007 (UTC)

Thanks for the info. That is interesting stuff. Anyway I found a link http://www.usatoday.com/tech/science/discoveries/2006-11-15-neanderthal-genome_x.htm . It is hard to tell without the actual journal articles whether they really will be able to get enough uncorrupted DNA to sequence a whole genome though. Lonjers 05:50, 21 March 2007 (UTC)

The new theory you read about is actually consistent with BOTH major theories, i.e. Out-of-Africa and multiregional. There is actually NOT overwhelming evidence for the Out-of-Africa theory - nuclear DNA evidence (as opposed to Y-choromosome and mtDNA) actually contradicts the Out-of-Africa theory. The new synthetic theory is kind of like an Out-of-AfricaX2 model. Anyway, the new model needs some time to get digested by the community, but it's important. On another note, because of the new model, all the pages on human evolution need a revamp. Yutgoyun 18:51, 23 March 2007 (UTC)

There's a link to the journal articles in the link you posted. Look here. I'm somewhat sceptical about AMH/Neanderthal breeding, and if it did happen it must have been small scale, modern humans are justall to similar for Europeans to have any significant Neanderthal ancestry compared to other modern humans. Significant Neanderthal ancestry for Europeans is not compatible with the fact that humans are so genetically homogeneous compared to other mammals, there would be far more between group diversity than there is. Long and Kittles wrote a very good paper showing that genetic diversity deacreases with distance from Africa, indicating a series of founder events from Africa. I don't think it's true to claim that most autosomal work contradicts the Out of Africa model, though some appears to be inconsistent with it. A great deal, probably most autosomal work supports Out of Africa. For example genetic diversity is greatest in Africa. See Tishkoff and Kid for example. Well maybe I'm just generally a sceptic, most people involved with science are. Cheers. Alun 19:26, 23 March 2007 (UTC)

[edit] references

1. ^ Multiple dispersals and modern human origins Marta Mirazon Lahr and Robert Foley 1994
2. ^ DNA sequences of Alu elements indicate a recent replacement of the human autosomal genetic complement
3. ^ A Geographically Explicit Genetic Model of Worldwide Human-Settlement History Hua Liu, Franck Prugnolle, Andrea Manica, and François Balloux The American Journal of Human Genetics, volume 79 (2006), pages 230–237