Before continuing with my "Later Migrations" scenario, I want to alert you to a couple things. First, Maju, has been posting some extremely interesting and relevant comments based on his own extensive research into the genetic evidence, particularly the phylogenetic trees for mtDNA haplogroups M and N and their derivative clades. Since he doesn't always agree with me, and has a more complete grasp of the genetic evidence than I do anyhow, I urge you to read what he has to say to get an informed and independent perspective. (Actually we aren't in total disagreement either, since we both agree that the evidence is not yet complete, and never easy to interpret.) Anyone seriously interested in the genetic evidence pertaining to the later migrations I've been speculating about should read his comments, especially those for
Post 291. Keep a lookout for some of the links he's posted to his blog, which is extremely rich in all sorts of interesting details and discussions of the genetic evidence (also some excellent political commentary, which I usually happen to agree with).
Second, I was reminded by one of the links on Maju's blog (
Leherensuge) of an especially relevant article, dating from 2005,
The Dazzling Array of Basal Branches in the mtDNA Macrohaplogroup M from India as Inferred from Complete Genomes, by Chang Sun et al. I'd read through this one already, but failed to notice an important detail, the Age Estimations for Haplogroup M, presented in Table 1:
South Asia 44.6 k ya
East Asiaa 69.3 k ya
Oceania 73.0 k ya
SE Asia 55.7 k ya
Though I feel sure Maju will complain that once again I'm concentrating too much on that which suits my purpose, it's impossible for me to ignore this additional evidence for a genetic gap exactly where I see a very significant cultural gap. For reasons that the authors themselves find difficult to explain, the M haplogroups confined mostly to South Asia are estimated by their own procedures to be significantly younger than those for East Asia, Oceania or Southeast Asia. To be consistent with a straightforward, continuous Out of Africa scenario, they should be older than the others, not younger. A very similar result was obtained by Soares et al (see
Post 262 for discussion). To be fair, I'll quote their explanation for what to them is clearly an anomaly:
The abnormal younger age (~44 x 10 cubed years) of the Indian M lineages may be attributed to the unequal age contributions from different M haplogroups to the total M age estimate. The frequency composition of the particular M haplogroups in a population sample from India then matters a lot because the ages contributed by the different branches range from 21 x 10 cubed years (M30a) to 93 x 10 cubed years (M6b). Our sample drawn for complete sequencing does not reflect the natural frequencies and therefore could bias the age estimation.
To investigate this, we simulated a natural frequency distribution by assigning the mtDNAs sampled from the Chenchu and Koya populations (Kivisild et al. 2003) to
their respective haplogroups by (near) matching control region motifs (Yao et al. 2002). Fewer than 5% of the mtDNAs were virtually unassignable, so that the remaining 142 mtDNAs could be used to evaluate the natural frequency of each M branch in [the] Indian population (table 2).
This method averaged out to a "better" result, 54.1 k years ago, but this date still makes the M's of India younger than the others. What also caught my attention was the fact that, of all the haplogroups represented in the Chenchu/Koya study, the three most clearly centered in the south and east are by far the oldest: M2a at 70.2 k ya; M2b at 77.1 k ya. Most notably, M6b, centered not only in the south and east, but also the extreme northwest (farthest from Toba), where we find so many tone languages, was found to be roughly 92.5 k years old! So not only are the M's of India younger than those of the other regions along the southern route, but the oldest ones in the subcontinent are closest to those regions that either would have been least affected by the Toba ash cloud, or, according to the theory put forth by Oppenheimer, are likely to have been resettled by groups migrating westward from Southeast Asia in the wake of the Toba event, after the natural environment of the region had once again become inhabitable.
It's Leherensuge. A Neomythical Romantic construct by Agosti Xaho, that means "the first and last serpent" (or dragon). Xaho based this idea on the myths of Herensuge (dragon, meaning last or third serpent) and the male half of the dual Basque God: Sugar, Sugaar, Sugoi or Maju (all but the last based on suge=serpent, though Sugar and Sugoi have also been sometimes interpreted from su=fire: su-gar = fire flame, su goi = flame (of?) high). Whatever the case the serpent and the black billy-goat were the most common ancestral symbols of Sugar and Mari, though they also manifest as humans, fireballs and Mari (the Goddess of female half of God) as red animals. Leherensuge would hence resemble the idea of the ouroboros or serpent biting its own tail, meaning some sort of eternal cycle, just as the eternal creation that seems to be the leit motiv of Basque mythology (when Sugar and Mari meet, each Friday night in some sacred cave at the nearby holy mountain, the witches' sabbat, they create the storms that bring fertility... and sometimes disasters). Just for the record.
ReplyDeleteOn topic:
ReplyDeleteCheck table 2. You have single sublineage dates that range between 70 and 93 Kya in some cases. And they are not even basal sublineages but already second level derived.
Beware of MC estimates (not any C14 at all) but very specially beware of paraphyletic groupings (all regional groupings are) and related misleading averages.
This method averaged out to a "better" result, 54.1 k years ago, but this date still makes the M's of India younger than the others.
ReplyDeleteNo. Because you should never care about the average of any paraphyletic group but about the clade specific estimates, if anything.
If M6b expanded (by this paper) c. 93 Kya and M40 expanded 39 Kya, these are two different phenomenons clearly. M40, M39 and the other lineages that have c.40 Kya estimates may have been part of the same process but M6b and M2 are clearly much older.
Always accepting these age estimates. I tend to be wary of molecular clock in general and consider it just an erudite speculation, not any proof of anything on its own merits (that are not too many).
... are likely to have been resettled by groups migrating westward from Southeast Asia in the wake of the Toba event...
ReplyDeleteBig problem here: none of all those South Asian M lineages has Eastern relatives (other than via the M or L3 nodes). So in principle no M migrated westward from SE Asia.
There must have been local demic flows in South Asia and Toba has not to be the only and absolute answer of every one of them.
If we go by the dates suggested in this paper only M2a would appear to have expanded right after Toba. Intead most lineages have expansion dates of c. 40 Kya, which suggests me some association with the novel microlithic technology, that appeared in South Asia c. 38 Kya, per recent research.
It may also be related with the HE4 cold event caused by the Campanian Ignimbrite eruption c. 40 Kya.
Just some ideas.
Maju: "Check table 2. You have single sublineage dates that range between 70 and 93 Kya in some cases. And they are not even basal sublineages but already second level derived."
ReplyDeleteThe absolute dates aren't realistic, admittedly, but what interests me are the relative dates. I'm not sure what it means for the oldest clades to be second level derived, but since I'm not an expert on this stuff (and neither are you) I prefer to go by what the experts have to say, at least until more information becomes available. I take all this stuff with a grain of salt, but I don't see the point of ignoring what could be significant evidence simply because I don't (yet) understand it.
I'm not sure what it means for the oldest clades to be second level derived...
ReplyDeleteThat they belong to even oldest haplogroups, which in turn are basal sublineages of M.
M > M2 > M2a/M2b
M > M6 > M6b
That means that, if M6b is (according to the paper) 95 Ky old, then M6 must be older and M even older. The grandmother can't be younger than granddaughter. And this metaphorical generational distance is of course not realistic: a lot more generations must have passed.
... but since I'm not an expert on this stuff (and neither are you) I prefer to go by what the experts have to say...
Well, I'm reasonably "expert". And you pick your experts according to whether their data fits with your pre-conceptions or not. You are choosing to ignore many other experts without any problem.
I think it's not an honest attitude on your side.
Maju: "Big problem here: none of all those South Asian M lineages has Eastern relatives (other than via the M or L3 nodes). So in principle no M migrated westward from SE Asia."
ReplyDeleteForget about the current geography, it's confusing you. We seem to have at least two sets of unrelated M lineages, but where they are now located means nothing. What's important is where they might have been during the Paleolithic. If Oppenheimer is right, all or most of the original OOA migrant settlements then living in India would have been destroyed as a result of the eruption, so what we see now is not a reflection of what was there prior to Toba.
Let's assume there were a few small Out of Africa migrant settlements strewn throughout the coast from India to SE Asia and possibly beyond. And let's assume that prior to Toba (assuming Toba is relevant) they were all simply basal M and still looked African and still practiced their original African traditions. Toba explodes, and all the settlements in India die out.
Certain surviving groups are now located to the east of India and let's say these can now be divided into three subgroups: subgroup A: those seriously affected by the eruption and now decimated, but with a few survivors remaining (major bottleneck); subgroup B: those originally located further to the east than group A, who have also suffered a bottleneck, but somewhat less severe; subgroup C: those originally located far enough to the east to be minimally affected, if affected at all.
As a result of the bottleneck, group A has lost many of its African traditions, but by chance has retained at least some of its original African morphology. Group B has lost many of its African traditions also, and also, again by chance, due to a post-Toba founder affect, now has an altered morphology, more like what we now see in East Asia. Group C remains more or less as is, with only a few losses of African traditions and a few changes of morphology.
After a thousand years or so, when conditions in India have improved, let's say that the descendants of group A head west, settle in India, do well and begin to expand. As they expand, the various branches of M that we now see in India begin to develop. For reasons that aren't completely clear, the descendants of group A stay put.
Meanwhile, group B, which experienced a less severe bottleneck, has remained more or less in place to the east of India, and, because less affected by the disaster, is able to expand more quickly than group A -- and thus would have had more of an opportunity to develop the M sublineages that we now see in Southeast Asia. Because B expanded more rapidly, it's M branches are older than those of A.
Group C, which was originally located farthest to the east, continues to migrate and expand throughout Southeast Asia and island SE Asia, and then continues its coastal migration northward along the Pacific coast, eventually becoming the earliest inhabitants of the Americas.
For much of this trip it retains its African traditions and morphology, but as the migration continues, C breaks into subgroups that experience various local bottlenecks that alter its traditions somewhat and also its appearance. Of course, by now it consists of several different groups, each of which develops somewhat independently. (Continued on next comment . . . )
We seem to have at least two sets of unrelated M lineages...
ReplyDeleteNo. That's my whole point: all M sublineages are related at the M node. All M people are descendant of a single woman who was the first one to carry this lineage with all its defining mutations.
Geography is totally irrelevant for that. Only phylogeny matters here.
If Oppenheimer is right, all or most of the original OOA migrant settlements then living in India would have been destroyed as a result of the eruption, so what we see now is not a reflection of what was there prior to Toba.
But if Oppenheimer is wrong, as so many suspect... then what?
Whatever part of reason he may have, the phylogeny is clear: M had a single very fast expansion (star-like structure) and the greatest basal diversity is in South Asia (so most probably expanded from there).
If your theory of the various groups would make any sense, we'd see the phylogenetic signature of each of those groups: something like M1, M2 and M3 (not the real haplogroups of those names but one for A, another for B and yet another for C). That signature is nowhere to be seen.
Hence your hypothesis is wrong.
I could extend myself further but the clarity of the error could not be more evident. Genetics, phylogeny to be more specific, falsifies your hypothesis.
You don't like it and try to grab a burning nail. Ok, too human not to understand that but I can't lie you on this just on compassionate reasons. My moral duty is to tell you the truth: you are drifting out from the reality of what actually happened.
(. . .continued from previous comment)
ReplyDelete[Minor correction to the above: for the most part group A stays put in India, but there may be an exception to that rule, which I'll be dealing with in an upcoming post.]
Meanwhile, group B also expands, but independently from groups A and C. Group B expands more or less as indicated in map C or the migration map published in the same paper, i.e., to the north and northwest, spreading its lineages to East Asia, Central Asia and beyond, to Siberia and, eventually, to Beringia, to form another group of Amerindian pioneers. At a somewhat later time, the descendants of group B also expand southward into Southeast Asia, Island SE Asia, etc., ultimately marginalizing the descendants of group C, who eventually can be found only in refuge areas. Some, though certainly not all, of these descendants of group C still retain at least some of their African traditions and morphology, though in different degrees in each case.
Now I'm not claiming this is what happened. We have no direct evidence of that. But I think this scenario gives us a rough idea of the sequence of events that could have taken place in the wake of the Toba disaster, or some other disaster centered in S. Asia, and that a scenario of this sort could explain a great deal, including the gap I've been pointing to, as well as the origins of "Mongoloid" morphology and some other "racial" differences, etc.
This sort of thing at least gives us something to work with, and of course something to poke holes in as well, which is fine with me. Have at it.
I understand your concept of three groups: essentially Caucasoids (A), Mongoloids (B) and pseudo-Australoids (C).
ReplyDeleteBut the genesis of these morphological groups must have happened AFTER the M and N expansion, not by founder effect but by some other processes of regional homogenization. Each of those groups has way too many founder lineages to be derived from a bottleneck event.
A rough count of the lineages (basal under M, N and R) gives:
South/West Eurasians (Caucasoids): some 30+ founder lineages (at least 25 if ignoring R)
East Asians (Mongoloids): some 15 founder lineages, 13 if ignoring R
Sunda/Wallacea/Sahul aboriginals: more than 10 founder lineages (of which only one belongs to R).
That is not the signature of three specific small survivor populations.
Neither does it suggest any particularly intense bottleneck or founder effect for Caucasoids (notice that most of the lineages of this group are in fact South Asian and nearly all the rest are shared between South Asia and West Eurasia). This group A (in your hypothesis) is in fact the most diverse of the three groups, not the less diverse.
Maju: "That means that, if M6b is (according to the paper) 95 Ky old, then M6 must be older and M even older. The grandmother can't be younger than granddaughter."
ReplyDeleteYes, of course, that much I understand very well. But it's not clear to me why the authors of this paper would bother to report such results if they make no sense. My guess is that there are questions regarding the design of the phylogenetic trees themselves, which are, after all, NOT strictly objective. The same data can produce several different trees, as I understand it, and different sorts of criteria are used to decide which is most "appropriate."
Maju: "Well, I'm reasonably "expert". And you pick your experts according to whether their data fits with your pre-conceptions or not. You are choosing to ignore many other experts without any problem.
I think it's not an honest attitude on your side."
It looks to me as though you are projecting your own dogmatic attitude onto me. You are the one who picks the experts who suit you and dismisses all the others, not me. I consider all the evidence as should be clear from following this blog. I even pay attention to you, despite all the insults. What really bothers you is that I don't always agree with you, but sorry I am not here to convince you that I am right, and have no need for your approval.
My guess is that there are questions regarding the design of the phylogenetic trees themselves, which are, after all, NOT strictly objective.
ReplyDeleteThey should be strictly objective. It's a matriushka doll of sets and subsets.
That doesn't mean they are not potentially subject to errors and specially to new findings of novel markers.
It looks to me as though you are projecting your own dogmatic attitude onto me. You are the one who picks the experts who suit you and dismisses all the others, not me.
I am not claiming the support of "the experts" as you do (I prefer to found my opinions on the hard data rather than someone else's opinions). And I have provided you with some of the materials you choose to prefer... but also with others you choose to disdain.
It's your (subjective) choice but do not pretend to be backed by the unanimous opinion of the academy. It is not the case at all.
... despite all the insults.
What insults? I'm warning you against being dishonest with yourself (first and foremost). It is not meant as any insult but as a friendly advise.
If you choose this or that route of research should not bother me the least, except because I believe that you were on a very good track with the potential of providing some excellent research but, now you seem too obsessed with the idea of a single catastrophic gap, and hence you choose to back up your hypothesis on some very specific school of population genetics (Oppenheimer), that is very much against the hard data.
I don't think anymore I can persuade you of reconsidering but I feel my duty to warn you against this one-sided approach that, in my humble opinion, is leading you to a cul-de-sac.
What really bothers you is that I don't always agree with you...
What really bothers me is that there is no genetic signal of the bottleneck that you are claiming is so central in your hypothesis. And it bothers me that even if you can perfectly understand why I say that there is no signal of any bottleneck at that stage, you avoid the problem by citing certain authorities but not others.
Ok. Your problem. I can't do much more.
Maju: "No. That's my whole point: all M sublineages are related at the M node. All M people are descendant of a single woman who was the first one to carry this lineage with all its defining mutations."
ReplyDeleteYes, they are all related at the M baseline. But beyond that there are two different sets of clades, one centered in South Asia, the other centered farther east. All or most of the South Asian lineages are confined to South Asia, right?
Maju: "But if Oppenheimer is wrong, as so many suspect... then what?"
Then we look at the possibility of some other disaster that could have affected more or less the same region. And if nothing pans out, then we are stuck without an explanation for something that needs explaining.
Maju: "If your theory of the various groups would make any sense, we'd see the phylogenetic signature of each of those groups: something like M1, M2 and M3 (not the real haplogroups of those names but one for A, another for B and yet another for C). That signature is nowhere to be seen.
Hence your hypothesis is wrong."
I'd be very surprised if the scenario I outlined would turn out to be consistent with the genetic evidence, that would be a huge stroke of luck. What I presented was intended to give us some idea of the sort of thing that could have happened. If it doesn't fit, fine, then we need to consider other scenarios that come closer to a fit.
You seem to see this as my problem. It's not. It's a problem for anyone seeking to reconcile the Out of Africa model with ALL the evidence we now see -- not just the genetic evidence, but the cultural and morphological evidence as well. And even as far as the genetic evidence itself is concerned, there is a clear discontinuity that needs to be explained, not just explained away.
I'm willing to admit I could be wrong about much or even all of what I've been proposing. But that doesn't eliminate the problem, sorry.
Maju: "I understand your concept of three groups: essentially Caucasoids (A), Mongoloids (B) and pseudo-Australoids (C)."
ReplyDeleteNot quite: Indian Tribals (including Australoids) (A), Mongoloids (B), and a continuation of the Out of Africa migrant "beachcombers" (C), destined to become Negritos, Melanesians, and ultimately the first wave of paleoindians, the ones that resemble Melanesians.
Maju: "Each of those groups has way too many founder lineages to be derived from a bottleneck event."
Good. Thank you. This is for me your most compelling argument so far. But a great deal of mixing and matching could have taken place after the bottleneck event. Read Oppenheimer's book and you'll see how he attempts to trace many of these developments from that one single event. I'm not saying his is the only meaningful interpretation or even that he's right. But we are getting into very complex terrain at this point and there is still much to be learned about how these various groups originated.
As far as Caucasians are concerned, I don't see them as one of my A, B or C groups, but possibly a later development, possibly along more or less the same lines you see.
Maju: "What really bothers me is that there is no genetic signal of the bottleneck that you are claiming is so central in your hypothesis. And it bothers me that even if you can perfectly understand why I say that there is no signal of any bottleneck at that stage, you avoid the problem by citing certain authorities but not others."
ReplyDeleteI've cited a great many sources, including some that present a problem from my point of view. But, if you can provide me with references to any sources that take issue with Oppenheimer or any other bottleneck proponent please include them in a comment and I'll be happy to post them on the blog.
That's not the way how scientist do their job: it's going to be hard to find a paper that directly attacks some other paper. That's considered "unpolite" and in modern mentality is the worst of all crimes.
ReplyDeleteSo what people does is ignore the theory and write and demonstrated their own alternative ones. If there is any direct discussion it happens at corridors, cafes, email lists or other less compromising venues.
You are not going to find that kind of argumentative materials. It's the kind of thing that scholars don't do anymore, with a very few exceptions.
You will nevertheless find zillions of materials that say the opposite without ever mentioning Oppenheimer, Toba or anything of the like.
But whatever. I have learned what I needed to learn here, I have taught you what I could. It's time to take a walk.
Not quite: Indian Tribals (including Australoids) (A), Mongoloids (B), and a continuation of the Out of Africa migrant "beachcombers" (C), destined to become Negritos, Melanesians, and ultimately the first wave of paleoindians, the ones that resemble Melanesians.
Your division is nonsensical. What's the difference between Indian tribals and Indian non-tribals and other Caucasoids. Didn't we agree that there was no particular India-Australia connection?
How can you connect Melanesians with "Paleoindians" genetically? It's impossible (beyond the general Eurasian connection).
Your obsession to describe certain tropical Eurasian peoples as more connected to Africa just because they retain ancestral tropical features is non-scientific, certainly not genetic. If anyone is more connected to Africa of all Eurasian peoples is us Caucasoids, even if only because of "recent" inputs across the wide frontier.
As I said, I have learned what I could, I taught you what I could. Good luck.
Maju: "I am not claiming the support of "the experts" as you do (I prefer to found my opinions on the hard data rather than someone else's opinions)."
ReplyDeleteThat's a very revealing statement, Maju. The fact is that the "hard data" in this field is often very difficult to interpret -- which is why so many different interpretations exist. You have set yourself up as an expert who can "read the tealeaves" better than anyone else, and that may be fine for you. I too have a big Ego, so I can understand your feelings. But it's not fine for me, because I have no reason to accept your opinion over that of "the experts."
"And I have provided you with some of the materials you choose to prefer... but also with others you choose to disdain."
I appreciate all the references you've provided, but you are wrong if you assume that I ignore any of them. If you look carefully, you'll see that I try hard to present other viewpoints and recently juxtaposed two opposing letters-to-the-editor as a topic for discussion.
You are also wrong in assuming that I am overly attached to the Toba theory and motivated to ignore all evidence that doesn't support it. First of all, there is only one aspect of all my work in this realm that I am adamant about, and that is the special relation between Pygmy and Bushmen music, based on their shared P/B traditions. I insist that this relationship can only be explained on the basis of an archaic survival of P/B among both groups. Which means that, for me, their music functions as a kind of time machine. On this matter I will fight tooth and nail because I am completely convinced of its truth.
As far as all the rest is concerned, I take it seriously but am definitely willing to adjust my thinking when and if contradictory evidence becomes available. It really does not matter to me if there was or was not a bottleneck associated with Toba or any other event during the OOA migration. If some other reason that makes sense is offered, with evidence to back it, then I'll be more than happy to explore that possibility. But nothing of the sort has appeared to date, so I am stuck with Toba or other Toba-like scenarios.
Maju: "That's not the way how scientist do their job: it's going to be hard to find a paper that directly attacks some other paper. That's considered "unpolite" and in modern mentality is the worst of all crimes."
ReplyDeleteThe geneticists seem to avoid controversy at all costs, I agree. But in most other fields, they fight tooth and nail, a good example being the Kalahari debates. But I think the main reason no one is challenging Oppenheimer is because the genetic evidence is not yet clear enough to base a judgement on, one way or the other. The archaeological evidence is thought to be the most decisive, but thus far it also seems inconclusive.
Maju: "Your division is nonsensical. What's the difference between Indian tribals and Indian non-tribals and other Caucasoids. Didn't we agree that there was no particular India-Australia connection?"
Actually no, we never agreed on that and I still see a connection.
"How can you connect Melanesians with "Paleoindians" genetically? It's impossible (beyond the general Eurasian connection)."
The difference between us, Maju, is that you are caught up in an ocean of data that is constantly changing and shifting. You yourself dismiss papers only a few years old as "out of date," yet you refuse to recognize that the "latest" work will also be out of date a few years from now. While the genetic evidence is obviously important, it must always be taken with a grain of salt. If you want to see the big picture you can't let yourself be distracted by evidence that may change by next month or next year.
The difference between us is a difference of perspective. Another problem is your refusal to accept that there is a difference between an exploration and an assertion. You assume you know what science is all about, but in my view you are extremely naive about how real science is done by real scientists, especially theoretical scientists. If Newton had let himself be paralyzed by the problem of the perihelion of Mercury, for example, and on that basis decided he must be wrong, because his theory didn't fit that evidence, then we might have had to wait another hundred years for any real advance in the theory of gravitation.
Any innovator in the sciences knows very well that there is a thin line between the visionary and the crackpot. We learn to live with the possibility that we could be all wet, because the rewards of exploring the unknown are so great.
In any case, I want to thank you, Maju, for being such a careful reader and critical commenter for so long. I've learned a lot from you and very much appreciate your contribution to this blog and to my understanding of the genetic evidence.