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Questioning the Out of Africa theory
(Note: Below, Stewart W. tells us about another website in addition to Mathilda’s that (a) challenges the established view that modern Homo sapiens moved out from Africa and completely replaced all earlier Hominid populations; (b) argues for a Eurasian origin of Homo sapiens; and (c) says that there was interbreeding between Homo sapiens and Homo erectus. After looking at the material, I summarize the main idea in my own words here.)-
Here are four comments posted by me at Mathilda’s Anthropology Blog over the weekend. She has replied to the first. The last three are awaiting moderation and have not yet appeared online.
Lawrence Auster // May 17, 2009 at 12:21 pm | Reply
To Mathilda,
Last night I read your “About” page where you reject the Out of Africa theory. I’m fascinated by this, because I had thought that OOA had decisively won the debate years ago. I had been persuaded by it, based on Nicholas Wade’s cogent account of the genetic markers that show the successive branching of humanity away from Africa.
So, could you tell me if this. If it’s not the case that the ancestors of all modern humans came from Africa, how do you explain the fact that all non-African males in the world have the same mutation on the Y chromosome, and that most or all sub-Saharan males lack it? Isn’t that conclusive proof that a group of people sharing that mutation left Africa and became the ancestors of all non-African humanity?
If you’ve discussed this elsewhere, please direct me to that post.
Thank you for your work.
mathilda37 // May 17, 2009 at 3:10 pm | Reply
Technically I go for a ‘weak Eden’ theory, which means mostly out of Africa. Selection has been shown to work on both Y and Mt DNA, and low level contributors can die out easily. Quite a few major human Y chr hg’s are MIA, and a couple of steps on the mt DNA are missing too.
There are multiple DNA studies that have concluded we have a low percentage of archaic human in us- there’s another one I’ve just posted today. All over which go massively under-reported in the popular media. What usually happens is that most studies which follow one marker or another will say OOA- which is fine and accurate for that one gene. BUT, a lot of Eurasian markers are over 1m years old and you don’t find them in Africans. Bit hard to explain with OOA. I’ve got four studies that I can name off hand that support low level archaic DNA in modern humans (and that say so in the text) and mutliple other studies on assorted ancient in Eurasia but not seen in Africa loci that have a TMRCA over over 250k- MC1R mutations particularly. It’s funny how they just seem to get ignored. Even the existance of one ancient non African gene is extremely damaging to the OOA theory- it’s a logical impossiblity if all ancestry is traceable to Africa from a reasonably recent event.
I put a few of them here. One day I’ll collect them all in one place for easy reference.
That and the morphology of early Europeans supports interbreeding—as multiple physical anthropologists have pointed out. I myself have a Neanderthal ‘long toe’. There’s a Trinkaus paper I have on here somewhere that goes into the details.
Not to mention- the later in time the Neanderthal the more like a modern human it looks- ‘transitional’ Neanderthals they get called. They get longer limbs, little chins.. Hybrids.
Lawrence Auster // May 17, 2009 at 4:50 pm | Reply
Thanks for the reply. In fact, just as I was reading it, I received this from a correspondent:
“Carleton Coon’s theory was based on the persistence of regional traits between subspecies of Homo erectus and the living human races, strongly suggesting that existing race differences are of pre-sapiens origin. Many of the dental and skeletal characters, for instance, of Homo erectus pekinensis, not present in other varieties of Homo erectus, are still to be found in the Mongolid race. Peking Man had hallow-shaped incisor teeth (a non-adaptive trait), a peculiarly shaped molar which gave him a high cheekbone appearance, and an interparietal bone, traits still very common in the Mongolid race but rare or nonexistent in other races.
“The truth appears to lie somewhere in between Coon’s multilineal theory and the popular unilineal theory. The fossil and genetic evidence suggests that the living races do reflect pre-sapiens regional lineages, but in a pattern subsequently modified by miscegenation between immigrant populations and the older aboriginal stocks. Mainstream proponents of multilineal theories of the origin of human races include Milford H. Wolpoff, Stan Gooch, Erik Trinkaus, Wu Xinzhi, Alan G. Thorne, James Calcagno, John Hawks, and Eugène Morin.”
I wrote back to him:
“You’re blowing my mind, because at this moment I’m reading Mathilda’s response to me at her blog, and (without mentioning Coon) she appears to be saying the same thing as he and you.”
However, according to both you (Mathilda), and my correspondent’s account of Coon, it would appear that the OOA is still true, wouldn’t it? That is, modern Homo sapiens originated in Africa and branched out from there, and then interbred with morphologically varying local types of an earlier hominid type, presumably Homo erectus, on different continents. So each of the different races or varieties of modern man have some ancestry from these different varieties of Homo erectus, but, at the same time, the modern human ancestry of all humans on earth still comes from Africa.
If this is the case, then your view is not a rejection of Out of Africa. Rather, it’s “Out of Africa, plus local admixtures of Homo erectus (or Neanderthal).” The OOA view is still true, but Carleton Coon’s theory that human racial differences originate prior to modern Homo sapiens is also true.
Do I have this right?
Your comment is awaiting moderation.
Lawrence Auster // May 17, 2009 at 5:03 pm | Reply
However, maybe I’ve misunderstood you, because you speak of “archaic humans,” not of Homo erectus. It seems to me that “archaic human” has an ambiguous meaning here. I’m only familiar with the use of “archaic” in this area when it’s used in the term “archaic Homo sapiens,” meaning Homo sapiens who preceded modern Homo sapiens, and who existed from approximately 200,000 kya to 100,000 kya. But you seem to be usng “archaic human” to refer to hominids that preceded Homo sapiens, such as Neanderthals or possibly Homo erectus. And, further, if you’re speaking of common ancestry that goes back one million years, as in the paper you quoted, then that would have to be Homo erectus.
Your comment is awaiting moderation.
Lawrence Auster // May 17, 2009 at 6:15 pm | Reply
While I’m intrigued by all this, I also find huge obstacles standing in the way of the idea that today’s humans are the offspring of interbreeding between modern Homo sapiens and Homo erectus.
The cranial differences between Homo sapiens and Homo erectus are vast. Clearly they are different species, as indicated by their very names. Therefore:
One, if erectus and sapiens mated, their offspring could not be fertile.
Two, if their offspring were fertile, then more erectus traits would have survived into the present than is the case. According to the Coon theory, the racial distinctions among Europeans, Africans, and East Asians stem from the erectus stage. But if these conspicuous morphological differences among the present races of mankind were carried down from the erectus stage, then why weren’t other and much more conspicuous morphological traits, such as the extreme brow ridges, the absence of a forehead, and the much smaller brain, also carried down?
[Note, May 19: Apparently Mathilda got tired of that thread or tired of my questions, as she hasn’t posted my comments after two days.]
- end of initial entry -
Stewart W. writes:
I’ve found another website, which appears to be by a well-informed amateur [Ronald Alan Fonda], and which proposes a variation of both Coon’s theory and the Out of Africa theory. In this hypothesis, fully modern humans have a Eurasian origin, not an African origin. They radiated out, interbreeding with the local H. erectus populations to produce the local variants observed. He says that this supports the supposed recent origins of certain genes, while simultaneously supporting the apparent older genetic material in many populations. His theory also explains the extant human genetic variance, related to the variance in the local H. erectus populations in various regions, specifically S.E. Asia and sub-Saharan Africa.
In one of the discussions on this site, he goes into some detail supporting the idea that H. sapiens and H. erectus are in fact the same species, separated by time rather than by genetic distance, and providing references to support that the two groups did interbreed and produce viable offspring.
One of the most interesting aspects of this theory is that it addresses the so-called “Australian Paradox,” in which the earliest inhabitants of Australia exhibit more modern morphology, while the subsequent immigrants show more primitive traits. The explanation is that as the first H. sapiens wave passed through the existing populations, they had less time to hybridize with the H. erectus locals, while the later, slower groups pick up more H. erectus traits on their way to Australia. [LA replies: That’s a very interesting theory.]
I haven’t seen this hypothesis discussed in many other areas, largely because of the politically incorrect implications (basically, that Europeans and N.E. Asians are closest to each other and to the fully modern humans, with other races being hybrids with various local H. erectus populations). It is nevertheless an interesting variant on your current discussion.
LA replies:
You write:
“… he goes into some detail supporting the idea that H. sapiens and H. erectus are in fact the same species, separated by time rather than by genetic distance, and providing references to support that the two groups did interbreed and produce viable offspring.”
Go to a museum and look for a long time at a Homo erectus skull, then look for a long time at a modern Homo sapiens skull, of whatever race. The differences between erectus on one side and modern Homo sapiens (of whatever race) on the other are profound, radical. The notion that erectus and sapiens are the same species just seems completely wrong to me. Further, not to disrespect Homo erectus, who lived on the earth for a million years and was a very notable species, but, to put it crudely, can you imagine a member of Homo sapiens being sexually attracted to a member of Homo erectus, with its huge brow ridges and no forehead, so that the top of the head goes straight back from the brow ridges? From a Homo sapiens point of view, it would be almost like mating with an ape.
But now I suppose someone will tell me I’m too fastidious, like Jerry Seinfeld.
LA continues:
This is from the home page of the linked website:
Please read Interbreeding Between Species
Before Age and Origin of the Human Species
The newest studies and comments by such renowned researchers as Tishkoff, Stringer, Wolpoff, Jorde, Kidd, Hagelberg, Harpending, Awadalla, Mountain (and dozens of other eminent scientists) published in the most prestigious journals, indicate:
1) Eurasian origin for modern humans, (Homo sapiens sapiens)
2) extensive interbreeding with Homo erectus and archaic sapiens, leading to
3) extant, hybridized populations whose characteristics reflect that ancestry
Analysis of genetic data falsifies the hypothesis that an “African Eve” was associated with the origin of modern humans, as well as claims that modern humans originated in and radiated “Out of Africa”.
Leonard D. writes:
You wrote:
“The cranial differences between Homo sapiens and Homo erectus are vast. Clearly they are different species, as indicated by their very names. Therefore:
“One, if erectus and sapiens mated, their offspring could not be fertile.
“Two, if their offspring were fertile, then more erectus traits would have survived into the present than is the case.”
The cranial differences between some modern humans are also large. Compare Europeans to Australian aboriginals. As for being different species—well, sort of. What exactly “species” means is not clear, even to biologists, as a quick perusal of wikipedia will demonstrate.
As for the fertility of interspecies hybrids, this is a well-studied problem, at least for animal species. Most hybrid types are never fertile, especially if the parents have different numbers of chromosomes. But others are fertile. Often hybrid embryos can be created, but they fail after some point in development. Not just any sperm/egg pair will work. Basically, the closer the relationship of the parent species, the more likely the hybrid will work. Since prehuman lines were very closely related species, it seems likely that they could interbreed, and that rarely the offspring would also be fertile. [LA replies: But obviously “rarely” wouldn’t be enough to creat the effects argued for.]
When Europeans displaced American Indians in the USA, very little interbreeding took place, even though it was 100% possible.
Thus, human population replacement events can look almost total. This is the truth that the “out of africa” consensus sees. However, some genes could survive from the losing species. Such genes, if they were disadvantageous or even just neutral, would most likely die out, being very rare in the winning species. However, if they were advantageous, then they would gradually increase and eventually come to dominate. They would look very much like novel adaptive mutations. However, at the genetic level, introgressed genes show different patterns (on average) than new mutations. Thus they can be detected statistically, given modern gene-sequencing. And they are being detected. [LA replies: what you say in this paragraph is very interesting.]
LA writes:
In the first linked article, “Interbreeding Between Species,” the author, Ronald Alan Fonda, says that different species in the same genus, such as dogs, wolves and coyotes in the genus Canis, can breed and produce fertile offspring.
Second, he says that many scientists (but not he) believe that sapiens and erectus are not different species, but different chronological stages of the same species. He quotes Douglas Futuyma on this point:
“Homo erectus and Homo sapiens are names for different, distinguishable stages in the same evolving lineage. They are chrono-species, rather than separate biological species. The two species names do not imply that speciation (bifurcation into two gene pools) occurred: in fact it probably DIDN’T in this case.”
What Fonda strongly argues for is that all species of genus Homo could and did interbreed:
… Accordingly, the entire genus Homo has probably been intER-fertile, just as the genus Canis is.
Clifford Jolly, writing in the American Journal of Physical Anthropology (2001; Supplement 33: 177-204) discusses the more apposite hybridization of hominins. He says,
”Another source of phylogenetic uncertainty is the possibility of gene-flow by occasional hybridization between hominins belonging to ecologically and adaptively distinct species or even genera. Although the evidence is unsatisfactorily sparse, it suggests that among catarrhines generally, regardless of major chromosomal rearrangement, intersterility is roughly proportional to time since cladogenetic separation.” And, ”any hominine species whose ancestries diverged less than 4 ma previously may well have been able to produce hybrid offspring”
[LA notes: in Wikipedia it says: “A hominin is a member of the tribe Hominini, a hominine is a member of the subfamily Homininae, a hominid is a member of the family Hominidae, and a hominoid is a member of the superfamily Hominoidea.”]
Four million years ago takes us back before Homo is recognized to have existed! And that is not even considering that Homo species have a longer generation time, so an equivalent number of generations would extend the potential hybridization period even further than 4 million years into the past. As an aside, this suggests that the genus Homo could have begun by hybridization. That would offer an explanation for why we are so closely related to the knuckle-walking chimps and gorillas, while Homo had bipedal ancestry. Of course, chimps and gorillas may have split off the line of descent from a common bipedal ancestor and reverted to knuckle-walking. The important point, with respect to interbreeding of species, is that hominin species separated by several million years of divergence can still produce fertile hybrid offspring.
Fonda concludes:
So all of the types of Homo living in the last few hundred thousand years would have been fertile with the other types. H. sapiens/sapiens and H. erectus and H. neanderthalensis would have all been able to interbreed … and the genetic evidence, as presented in the papers posted on this site, indicates they DID interbreed, resulting in the modern populations.
And, again, as Stewart put it at the beginningo his comment, the interbreeding between different species of Homo is central to the multi-regional, non Out of Africa thesis.
LA writes:
I’ve read part of the second article by Fonda, “Age and Origin of the Human Species,” but his writing is so dense, difficult, and ungenerous to the ordinary reader’s understanding, that he might as well be a geneticist or paleoanthropologist rather than an “epistomologist,” which is how he describes himself. He doesn’t write in normal expository English, but in compressed, technical shorthand.
However, the basic idea, though the scandalous, “racist” Carleton Coon is never mentioned, is basically Coon’s idea: that the genetic diversity of the human race is too great to have appeared within the last 100,000 years, which is the age of modern Homo sapiens, or even the last 200,000 years, which is the age of archaic Homo sapiens. Therefore, as astonishing as this sounds, the genetic diversity of humanity must have preceded the appearance of Homo sapiens itself, meaning that it is the diversity of Homo erectus. And therefore the diversity of today’s humanity must be the result of interbreeding between Homo sapiens and various older-than-sapiens, Homo erectus populations which were the actual sources of the diversity.
I have no position on this theory; I’m just trying to understand what its proponents are saying (though, as indicated above, I am personally doubtful of the notion of interbreeding between Homo sapiens and Homo erectus). However, I have to point out the irony that even as liberals such as Alice Roberts are trying to push the racial differentiation of humanity ever closer to the present, even suggesting, as Nicholas Wade does in an astonishing though entirely unsupported passage of his book, that the differences between the races didn’t appear until 12,000 years ago, others in the paleoanthropology field are pushing human racial diversification radically further backward in time, to 500,000 or a million years ago.
Posted by Lawrence Auster at May 18, 2009 02:39 PM | Send
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