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As it seems that there is a lot of confusion (including myself) on where are the various L(xM,N) lineages found and therefore on the patterns of spread of earliest humankind, I'm taking notes from Behar 2008 (specifically the figure S1).
Here it goes L0 (only CR mutations considered, marked as ">").
>>>>>>>>>L0
_________>>L0a'b'f'k
___________>>>>>L0a'b'f
________________>>>L0a'b
___________________>>>>L0a
_______________________>L0a1
________________________>L0a1a [Nile, Burkina, scattered, Bissau, Chad]
________________________>>L0a1b [L0a1b*: Sudan, Chad]
__________________________>L0a1b1 [S. Africa, Morocco]
__________________________>L0a1b2 [Arabia]
________________________>>L0a1c [Ethiopia, Iran]
________________________>L0a1d [Ethiopia, Yemen]
_______________________>>>>>>>>>>>L0a4 [Kenya]
_______________________>>>>>>L0a2
_____________________________>>L0a2a
_______________________________>L0a2a1 [SA, Kenya]
_______________________________>>L0a2a2 [SA, Arabia, Sindh]
_____________________________>>>>>L0a2b [Pygmy]
_____________________________>>>>>>>>L0a2c [Ethiopia]
_____________________________>>L0a2d [Kenya]
_______________________>>>>>>>>>>>>>L0a3 [Chad]
____________________>>>>>>>>>>L0b [Ethiopia]
_________________>>>>L0f
_____________________>>>>>>>>>>>>>>>>>>L0f1 [SA]
_____________________>>>>L0f2
_________________________>>>>L0f2a [Ethiopia]
_________________________>>>>>>>>>>>>>>>>L0f2b [Oman]
___________>>>>>>>>>>>>>>>>>>>>>>L0k
_________________________________>>>>>>L0k1 [Khoisan]
_________________________________>>>>>>>>L0k2 [Yemen]
_________>>>>>>>>>>L0d
___________________>>L0d1'2
_____________________>>>>>L0d1
__________________________>>>>L0d1a [Khoisan, SA]
__________________________>>>>>>L0d1c [Khoisan, SA]
________________________________>>>L0d1c1 [Khoisan, SA]
__________________________>>>>L0d1b [Khoisan]
_____________________>>>>>>L0d2
___________________________>>>>>>>>L0d2a [Khoisan, SA]
___________________________>>>>>>>>>>>>L0d2b [Khoisan]
___________________________>>>>>>>>>>>>>L0d2c [Khoisan, SA]
___________________>>>>>>>>>>>>>L0d3 [Khoisan, Kuwait]
Notes: "SA" means Southern Africa (non-Khoisan), "Arabia" means Arabia peninsula when several locations mentioned. L0 and its two basal sublineages in bold type (for clarity).
Considerations:
While L0d looks very much Khoisan-specific and hence part of the earliest split of Humankid, L0a'b'f'k appears to have a more northernly center of expansion.
L0a would appear to have got an East African urheimat, however it's widely scattered, with some very old lineages only found in North Africa, Peninsular Arabia or even as far East as Iran (see fig. S1 of the paper for details), which can't be considered part of the slave trade.
L0b is Ethiopian, L0f Ethiopian and Omani (again too old the split to consider it part of the slave trade), while L0k is found among Khoisan and Yemenis (and again it looks as an old split).
Other lineages are dealt with in the following threads:
· L1
· L2 and L5
· L3'4'6
Considerations:
While L0d looks very much Khoisan-specific and hence part of the earliest split of Humankid, L0a'b'f'k appears to have a more northernly center of expansion.
L0a would appear to have got an East African urheimat, however it's widely scattered, with some very old lineages only found in North Africa, Peninsular Arabia or even as far East as Iran (see fig. S1 of the paper for details), which can't be considered part of the slave trade.
L0b is Ethiopian, L0f Ethiopian and Omani (again too old the split to consider it part of the slave trade), while L0k is found among Khoisan and Yemenis (and again it looks as an old split).
Other lineages are dealt with in the following threads:
· L1
· L2 and L5
· L3'4'6
Update (Mar 8): corrected L0d3, which included two more basal mutations than actually has.
25 comments:
big question , but first would like to thank u 4 posting this info. it is a real eye opener.
1st. how old is L0a in angola or the western regions because a person recieved an awnser back from the africandna kit saying their match(hvr1-hvr2) is more close to angola. Is L0a in angola and western places different from its ancestral eastern kin.
2. how much frequency of L0a is there in angola?
ou're welcome. I take this as an open notebook, so I guess that the kind of stuff I post has irregular quality, though hopefully improving.
As for your questions, I have never worked to that detail but I can see in Tishkoff 2007 that L0a seems most common among Pygmies and some Niger-Congo (Bantu) peoples of East Africa like the Turu. These may have picked the L0a lineage while crossing the jungle in Eastward direction (Pygmy influence is somewhat apparent in some Eastern Bantus, I'd say) or alternatively it may be a residue in East Africa, where L0 has its greatest diversity, from before when proto-Pygmies colonized the Congo basin.
I can't say much more but the Pygmy link appears to be telling that L0a in Angola (Middle African Jungle area) is very very old.
While I did an exercise after this African mini-series, where I estimated the age of L0a to c. 79 KaBP, now I'd push that age backwards at least 20 Ka more (c. 100 KaBP), maybe even to c. 130 KaBP if the OoA is to be pushed to the earliest possible dates. Whatever the case, L0a as such should be very very old, it must have coalesced before L3, what also means before any migration out of Africa.
Btw, notice that I have split the blog and now I write on anthropology, genetics and such at http://forwhattheywereweare.blogspot.com/ - cheers.
pygmies are funny. however is it their diet that could be the reason for their stature or they messed with the wrong witch? their facial features can be matched with alot of s. yemenis i have seen though who are not a very tall people themselves
IF a long tail indicates a period of drift in a single, small, isolated region, and leaving aside the problems with the molecular clock, we see that L0 has a stem of 9 mutations before it separates into L0a'b'f'k and L0d. L0d is virtually confined to the Khoisan and has a stem of a further 12 mutations before it breaks up into L0d1, L0d2 and L0d3 a little before L3's expansion at 23 mutations.
L0d looks most likely to be just the southern relation of L0a'b'f'k. The latter haplogroup looks to have emerged north from wherever it was that L0 had developed its long stem. L0k looks not to have moved very far though. It developed a stem of 22 mutations before one or more members reached the Yemen, long after any meaningful OoA. L0a'b'f on the other hand looks to have slowly spread through desirable habitats into northern and western Africa, members possibly emerging from Africa with L3. My guess is that they actually emerged somewhat later than that. They were part of a second wave that didn't move as far.
"IF a long tail indicates a period of drift in a single, small, isolated region"...
It does not mean what you want it to mean but what it actually means: "no fucking idea what happened between those two nodes".
All the rest is consequently wrong.
"no fucking idea what happened between those two nodes".
You might have no idea but everybody else knows exactly what a long stem means.
You is not "everybody else".
"You is not 'everybody else'".
No. A fewe ignorant people cannot see it. And check out the analysis I made of L0 and you will see that such a scenario fits the evidence absolutely.
"A few ignorant people cannot see it".
I'll explain, as you seem not to be able to see it. A long stem at the base of a haplogroup can only be a product of drift. Concerning drift, this from Wiki:
http://en.wikipedia.org/wiki/Genetic_drift
"The law of large numbers predicts little change over time due to genetic drift when the population is large. When the reproductive population is small, however, the effects of sampling error can alter the allele frequencies significantly. Genetic drift is therefore considered to be a consequential mechanism of evolutionary change primarily within small, isolated populations".
Seems fairly definite: small, isolated populations. And, in case you're claiming that this is a modern concept, and not generally accepted, how's this quote from my ancient genetics text book (D. S. Falconer 1964, 'Quantitative genetics'):
"Before we can justifiably attribute these phenomena [differentiation between the inhabitants of different localities, and differences between successive generations] to random drift, therefore, we have to know (a) that the effective population size is small enough, (b) that the subpopulations are well enough isolated (or the size of the 'neighbourhoods' sufficiently small), and (c) that the genes concerned are subject to very little selection."
So there you have it. Small, isolated populations. Any single one of the three above population characteristics are unlikely to hold for a mobile population, let alone all three characteristics hold for a mobile population. Perhaps you can provide a reference that shows the above requirements for drift are no longer applicable.
A haplogroup is not a population: it can actually be just one in a larger population, and in that case drift tends to work against it... but maybe not to the point of extinction but rather keeping it reduced for long enough (sure: many others probably succumbed but of course not the surviving ones).
Also a "small isolated population" can exist "on the march", very specially if the march takes place through rther hostile environments like semideserts or areas already densely populated.
Anyhow, drift does not create mutations but prunes the tree only (or even chops it altogether).
Drift actually should act as enforcer of the established mtDNA structure (because novel mutations are rare enough,so chances are heavily biased against them), except in very small populations where old and new get more equivalent opportunities.
But all that says nothing about where the very small populations (or phylogenetically distinct subsets of larger populations) actually existed.
Environmental hostility seems a requirement for small size in any case and this can be natural (desert) or artificial (high densities). In both cases there is a situation of "lack of room" to expand that keeps the lineages restricted.
But, as soon as they arrive to an open niche, they must have expanded quickly.
So in fact, it is a practical impossibility that a long-stemmed haplogroups which expanded at the end of the stem would have evolved in destination. They must have evolved at origin (parent node's homeland) or on the road. Because their expansion signals their arrival to a new open niche.
Q.E.D.
Let me know if you find a single exception. I can't.
PS - As I know you are more stubborn than brilliant, I insist: small haplogroups which never experienced a star-like expansion are trivial in this debate.
"A haplogroup is not a population"
Nor is a gene.
"in that case drift tends to work against it... but maybe not to the point of extinction but rather keeping it reduced for long enough"
Obviously once a population becomes reduced to a single haplogroup that haplogroup cannot become extinct. Unless the whole population becomes extinct.
"Also a 'small isolated population' can exist 'on the march', very specially if the march takes place through rther hostile environments like semideserts or areas already densely populated".
I realise such is possible. But the 'march' will not be very far through any hostile environment or the group would die out along the route. Such movement is likely to be no more than from one oasis to the next, and any currently surviving haplogroup is unlikely to have been just a small proportion of a wider haplogroup collection.
"Anyhow, drift does not create mutations but prunes the tree only"
Leaving just one haplogroup, exactly as the references and I have been claiming all along. That one haplogroup will survive through its descendants even if the 'original' haplogroup dissappears. Hence we get a stem.
"Drift actually should act as enforcer of the established mtDNA structure"
But it leads to a reduction in mt-DNA diversity in a population of limited size. That is what we're dealing with in the example of haplogroups with a stem of any length.
"because novel mutations are rare enough,so chances are heavily biased against them), except in very small populations where old and new get more equivalent opportunities".
Exactly. That's why we get 'stems' developing in populations of limited numbers. That would have been the case through much of the Paleolithic.
"But all that says nothing about where the very small populations (or phylogenetically distinct subsets of larger populations) actually existed".
We can form a good idea from the distribution of the descendant haplogroups. Descendant haplogroups are very likely to have eventually spread from the confined region where the drift originally occurred.
"Environmental hostility seems a requirement for small size in any case and this can be natural (desert) or artificial (high densities). In both cases there is a situation of 'lack of room' to expand that keeps the lineages restricted".
The particular haplogroup need not be suffering the necessity of surviving in a desert. It may merely be isolated by surrounding desert, of rainforest, or sea, or mountains. In the case of high density all the minor haplogroups would tend to die out, leaving the haplogroups that were originally the main component.
"But, as soon as they arrive to an open niche, they must have expanded quickly".
'Arriving' would not be the usual catalyst for expansion. A population hemmed in by environmental factors is very unlikely to expand very far at all. Change in environmental conditions would be the more normal situation.
"So in fact, it is a practical impossibility that a long-stemmed haplogroups which expanded at the end of the stem would have evolved in destination".
Exactly my point. They would have arrived at their 'destination' first, and then developed their stem.
"They must have evolved at origin (parent node's homeland) or on the road".
No. It is the 'parent' haplogroup that expanded at some opportune moment, leaving its descendants scattered along the route, where subsequent isolation through changing conditions led to drift in the several widespread populations.
"Because their expansion signals their arrival to a new open niche".
Not their 'arrival'. The development of their ability to exploit the niche, whether through a change of climate or the development of a new technolgy.
"Let me know if you find a single exception. I can't".
Every single example of a haplogroup with a stem of any length can be interpreted as above. It is possible to interpret a very few otherwise, but they too can be easily interpreted as above.
"I insist: small haplogroups which never experienced a star-like expansion are trivial in this debate".
Rubbish. They are often most revealing. In all cases they can be shown to have developed in situ after the expansion of the ancestral haplogroup, often many mutations earlier. Try having a look at the many 'small haplogroups which never experienced a star-like expansion' from that point of view. I'm sure you will find it illuminating.
"But the 'march' will not be very far through any hostile environment or the group would die out along the route"...
Tell that to the Roma... or to the Malagasy!
You make so many subjective judgments and issue them as alleged "evidence"...
"Leaving just one haplogroup"...
Or 30! It depends. Why are you so dogmatic?
"But [drift also] leads to a reduction in mt-DNA diversity in a population of limited size".
Maybe but the population would also be generating novel mutations and incorporating migrants. Even the most inbred populations don't exist in a lab tube and have internal structure as well, differing form district to district but with all districts interacting to some extent.
This is real life, not an abstract sterile lab environment. "Pollution" is the norm, "purity" an absurd idea.
I mean: sex is all about remaining impure: about mixing blood, fluids and the very essence of life: DNA! People (as animals and plants) have to mix or be penalized for it in the mid run. It's pure Darwin!
"That's why we get 'stems' developing in populations of limited numbers".
I agree with this but not with the absurd idea of the small population remaining small for millennia like a hibernating seed only to flourish suddenly in the same environment that had hindered its expansion before.
No: that does not happen (unless major climatic changes take place). The population remains small because it is constrained by the environment and, normally, it only finds room for expansion after emigrating to a "promised land" of sorts, an open niche, where it can bloom.
"The particular haplogroup need not be suffering the necessity of surviving in a desert. It may merely be isolated by surrounding desert, of rainforest, or sea, or mountains".
Not important. You're just painting with (some particular) colors (favorite of your imagination) my draft. The image shown is fundamentally the same.
"'Arriving' would not be the usual catalyst for expansion".
I think it is the normal trigger of expansion: a small population discovers a good land (which is mostly empty or the previous occupants can be driven off) and, naturally, explodes.
"Change in environmental conditions would be the more normal situation".
No. It can be in some circumstances, I guess, but I do not see any reason to consider it the normal trigger at all.
You'd need to prove it reasonably for each and every case anyhow (or at least a large proportion of them), what is a daunting challenge which will take you the rest of your life probably.
It's not 100% impossible but in most cases (best example is M), we can see easily how haplogroups expand upon reaching an "empty" fertile land (South Asia in that case). Excepting R maybe (??), I can't find many star-like structures, much less large ones, that does not happen in a frontier area or in the context of major technological change (notably Neolithic in the West).
Only a few in Africa and one in South Asia are dubious but they are probably, I guess, best explained as product of technological advances, rather than climate.
I said: "So in fact, it is a practical impossibility that a long-stemmed haplogroups which expanded at the end of the stem would have evolved in destination".
You replied: "Exactly my point. They would have arrived at their 'destination' first, and then developed their stem".
How come exactly your point"?! We are saying exactly the opposite!
"Every single example of a haplogroup with a stem of any length can be interpreted as above".
So according to you mtDNA L3(pre-M) instantly migrated to Sindh at the OoA and then stayed there in almost strict monastic abstinence until the time came at the third mutation and then suddenly boomed into almost 50 different sublineages?
That's ridiculous!
Don't waste my time with that, please. I can imagine that you are thick enough to insist in your so obvious error but it's a waste of time for both: you should chew on this most clear case of M before you write a line further.
"Tell that to the Roma... or to the Malagasy!"
There were large numbers involved in both those migrations. Any stems formed? And we can see their origins exactly. They moved as 'origin' haplogroups, although some subgroups have evolved locally since the migrations.
"Or 30! It depends. Why are you so dogmatic?"
Not 30 if the surviving haplogroups have a long stem.
"Maybe but the population would also be generating novel mutations and incorporating migrants".
Not if the population is isolated enough to be developing a long stem.
"I mean: sex is all about remaining impure: about mixing blood, fluids and the very essence of life: DNA! People (as animals and plants) have to mix or be penalized for it in the mid run. It's pure Darwin!"
If the population is isolated enough to be subject to drift that mixing will not be happening.
"I agree with this but not with the absurd idea of the small population remaining small for millennia like a hibernating seed only to flourish suddenly in the same environment that had hindered its expansion before"
The only way a haplogroup can develop a long stem is if it fails to produce a diversity of surviving lines. In order to produce a long stem a population must remain small, and isolated, for quite a number of generations. I'm surprised you are unable to see that. A population that has remained isolated for some time is very unlikely to be able to expand suddenly through exactly the environment it has been unable to expand through for so many generations. Environmental change is the only possible explanation. Or change in technology.
"The population remains small because it is constrained by the environment and, normally, it only finds room for expansion after emigrating to a 'promised land' of sorts, an open niche, where it can bloom".
How come it can suddenly expand to a promised land it has been for so long prevented from expanding into? That is a very strange belief you have.
"I think it is the normal trigger of expansion: a small population discovers a good land"
And how does it do that if it has been prevented from doing so for long enough to form a stem of any reasonable length? Flying saucer? When a small population discovers a new land we invariably see its close relations remaining nearby. So populations never move very far from their origins into a new land although once they have been able to enter a new land they often range far and wide through it. And we find their relations widely scattered through it. In fact we can often trace the route they took from the string of relations remaining along it.
"It's not 100% impossible but in most cases (best example is M), we can see easily how haplogroups expand upon reaching an 'empty' fertile land (South Asia in that case)".
But that haplogroup was prevented from entering South Asia for some time. How would it be suddenly able to move if not change in environment?
"I can't find many star-like structures, much less large ones, that does not happen in a frontier area or in the context of major technological change".
Yes. Technological change will do it. But a star-like expansion will not be suddenly possible for a haplogroup with a long stem without such a technological or environmental change. Otherwise the expansion will have occurred as soon as the haplogroup had got anywhere near the desirable habitat. Consequently: no stem.
"How come exactly your point?! We are saying exactly the opposite!"
Sorry. I misunderstood what you were getting at. I agree that the long stem would have evolved in a single place before the subsequent expansion.
"So according to you mtDNA L3(pre-M) instantly migrated to Sindh at the OoA and then stayed there in almost strict monastic abstinence until the time came at the third mutation and then suddenly boomed into almost 50 different sublineages?"
Not quite as you put it. L3 emerged from Africa and evolved into M, but nowhere near Sindh. Possibly near the 'Arabian Oasis' of recent papers. There it developed its stem of 3 mutations before it was able to enter Northwest India/Pakistan as already formed M. It rapidly 'boomed into almost 50 different sublineages', especially once it had entered Northeast India.
"you should chew on this most clear case of M before you write a line further".
I think it is you who needs to re-examine your ideas concerning haplogrouop expansion. Is it the case that you have M evolving in Africa and then 'instantly migrated to Sindh at the OoA'? Where do you believe that M developed its stem?
"The only way a haplogroup can develop a long stem is if it fails to produce a diversity of surviving lines. In order to produce a long stem a population must remain small, and isolated, for quite a number of generations. I'm surprised you are unable to see that."
I can perfectly see that in general terms.
BUT a population (and hence their haplogroups) can't remain small if the econiche where they are is widely open: they must grow as soon as they set foot in that land, so, IF the population shows signs of clear expansiveness (star-like structure) the stem MUST be from earlier, from the migrant or pre-migrant period.
"But that haplogroup was prevented from entering South Asia for some time. How would it be suddenly able to move if not change in environment?"
I don't care (that's what we say in colloquial Spanish: 'pajeo mental': mental wanking). The fact is: M has three defining mutations which must have coalesced before arrival to the lush fields of Sindh (and Gujarat and all South Asia in general), because once there, M could just boom and actually did boom massively.
"But a star-like expansion will not be suddenly possible for a haplogroup with a long stem without such a technological or environmental change".
The environmental change is the arrival to an open niche, you blind stubborn old goat!
"L3 emerged from Africa and evolved into M, but nowhere near Sindh. Possibly near the 'Arabian Oasis' of recent papers. There it developed its stem of 3 mutations before it was able to enter Northwest India/Pakistan as already formed M. It rapidly 'boomed into almost 50 different sublineages', especially once it had entered Northeast India".
LOL, that's nowhere near your hypothesis. By your hypothesis M could only expand in the Persian Gulf Oasis (not "Arabian"). But it did not: it only expanded when arriving to South Asia.
That's exactly what I say: the stem develops before arrival to an open niche, at least in most cases, of which the example of M is paradigmatic.
You've managed to kick your own ass. Congratulations!
"Where do you believe that M developed its stem?"
On the march from East Africa to South Asia, a hunch is: one mutation in Yemen, another in Oman (or the Persian Gulf Oasis) and the final one in Balochistan, at the gates of South Asia.
The hunch is just a hunch anyhow, because it doesn't really matter because we can't know with any certainty. All we can know is that it exited Africa as L3* and arrived to South Asia as evolved M (L3m).
Full stop. No more mental wanking on what was the great-great-grandmother of M doing on May 15th 83,237 BCE at 7 pm GMT. That's idiotic. At most could make sense for fiction writing, nothing else.
"On the march from East Africa to South Asia, a hunch is: one mutation in Yemen, another in Oman (or the Persian Gulf Oasis) and the final one in Balochistan, at the gates of South Asia".
Your 'hunch' is very unlikely to be correct. The population involved was reduced to the descendants of just one woman, not just once but three times. That is unlikely to be sustainable in a migrating population. On the other hand it is exactly the sort of thing we would see in a small, isolated population confined to a small region. Besides which any haplogroup marching through any ecosystem capable of supporting it would be expected to leave small numbers along the way. These would survive to leave their own descendants of related haplogroups.
'All we can know is that it exited Africa as L3* and arrived to South Asia as evolved M (L3m)".
And we agree on that. But you seem not to accept that the stems of haplogroups are a product of drift. What is your explanation for the many stems we see in modern haplogroups?
"BUT a population (and hence their haplogroups) can't remain small if the econiche where they are is widely open"
And such a population will not be subject to drift. And so develop no stem.
"IF the population shows signs of clear expansiveness (star-like structure) the stem MUST be from earlier, from the migrant or pre-migrant period".
Again, we agree. But the stem can only develop through drift, which occurs only in small isolated populations. There is no other explanation possible.
"M has three defining mutations which must have coalesced before arrival to the lush fields of Sindh (and Gujarat and all South Asia in general)"
And we agree on that. Where we disagree is whether those mutations developed through drift or through some other method.
"LOL, that's nowhere near your hypothesis. By your hypothesis M could only expand in the Persian Gulf Oasis (not 'Arabian'). But it did not: it only expanded when arriving to South Asia".
Strange you should claim that. As far as I'm aware many still argue over whether M1 is SW Asian or African in origin. Such confusion is only possible if its origin is somewhere close to both regions. And, as far as I'm aware, M1 is not at all common in South Asia, so cannot be from there.
"That's exactly what I say: the stem develops before arrival to an open niche, at least in most cases, of which the example of M is paradigmatic".
Correction: 'the stem develops before the ability to expand into an open niche, in virtually all cases, if not actually in all cases'.
"The environmental change is the arrival to an open niche, you blind stubborn old goat!"
You are definitely being the stubborn old goat here. How can any population move through an inhospitable environment over a period long enough to develop any sort of stem?
"I can perfectly see that in general terms [The only way a haplogroup can develop a long stem is if it fails to produce a diversity of surviving lines. In order to produce a long stem a population must remain small, and isolated, for quite a number of generations. I'm surprised you are unable to see that]."
So we are getting somewhere. Regarding mt-DNA M1 in Africa:
http://maxwellsci.com/print/crjbs/v2-380-389.pdf
I will point out that I think the author is wrong, though.
"The population involved was reduced to the descendants of just one woman, not just once but three times".
I'm not saying that. Nor denying it either.
It's you the one obsessed with the possibly incorrect idea of one haplogroup = one population. And then running in circles around it.
"But you seem not to accept that the stems of haplogroups are a product of drift".
I have no problem with that idea at all. I just do not agree with the overly simplistic scenarios around it that you build as "necessary" (being only "possible" and maybe even "unlikely" in fact).
All the rest seems to be solved at this point.
All I say is that what arrived to South Asia was not pre-M, maybe unevolved L3-root (per your "in situ stem" hypothesis), but fully evolved M, which then boomed massively. That it was impossible for M to "drift" a long stem in South Asia.
And, as it was the case for M, it was surely for all (or most) other star-like haplogroups: they boomed upon arrival and coalesced ("drifted") their stems 'on the march' (prior to arrival to their open niche destination).
This is radically different from your "ad nauseam" repeated hypothesis of stems coalescing at destination only and necessarily.
"M1"
M1 is a descendant of a larger haplogroup whose greatest basal diversity is AFAIK in South Asia.
Focus! Quit stalling!
"How can any population move through an inhospitable environment over a period long enough to develop any sort of stem?"
Hostile environments do precisely that: keep the population small, enhancing drift. What doesn't kill you makes you inbred, ha!
"I'm not saying that. Nor denying it either [The population involved was reduced to the descendants of just one woman, not just once but three times]".
How can it be anything else? You have a haplogroup with a stem of three mutations, each of which left just one descendant haplogroup. So, at some stage, the population must have been reduced in turn to descendants of each of just one haplogroup.
"It's you the one obsessed with the possibly incorrect idea of one haplogroup = one population. And then running in circles around it".
'Possibly incorrect'? If we have drift leading to the survival of a single line then we must have a population of just one haplogroup. If a population consisting originally of more than one haplogroup is subject to drift the minority haplogroups will be extinguished.
"I have no problem with that idea at all. I just do not agree with the overly simplistic scenarios around it that you build as 'necessary' (being only 'possible' and maybe even 'unlikely' in fact)".
You seem to have a major problenm accepting that drift is only possible in small isolated populations. What alternative do you offer?
"All I say is that what arrived to South Asia was not pre-M, maybe unevolved L3-root (per your 'in situ stem' hypothesis), but fully evolved M"
I agree that 'fully evolved M' arrived in South Asia. But fully evolved M evolved in some other region (close to Africa) that L3 had managed to reach. There it remained isolated long enough to form a three mutation stem before being able to expand in turn.
"That it was impossible for M to 'drift' a long stem in South Asia".
I have never claimed that it did. I have always claimed M developed its stem before it entered South Asia.
"And, as it was the case for M, it was surely for all (or most) other star-like haplogroups: they boomed upon arrival and coalesced ('drifted') their stems 'on the march' (prior to arrival to their open niche destination)".
I keep telling you that it is most unlikely that any haplogroup has ever developed any sort of stem 'on the march'. In fact you almost agreed recently when you wrote:
"I can perfectly see that in general terms [The only way a haplogroup can develop a long stem is if it fails to produce a diversity of surviving lines. In order to produce a long stem a population must remain small, and isolated, for quite a number of generations]".
Surely if even just the 'usual' situation is that a haplogroup develops a long stem in a small, isolated population then we should accept that as our first suspicion in all cases. We should only look for an alternative explanation if the above explanation is absolutely impossible.
"M1 is a descendant of a larger haplogroup whose greatest basal diversity is AFAIK in South Asia".
No-one but you accepts that basal diversity is an unfailing guide to region of origin.
"Hostile environments do precisely that: keep the population small, enhancing drift. What doesn't kill you makes you inbred, ha!"
And extremely unlikely to be capable of moving very far at all.
Terry, I could discuss all this before a beer or seven... but online in text form I can't. Not with your continuous questions that have obvious answers and your butchering of my discourse into tiny disconnected pieces.
You just do not seem to understand anything at all and I cannot care anymore. If you want private classes, pay for them. If you want an intellectual buffon for your amusement, pay for that as well.
"Terry, I could discuss all this before a beer or seven... "
That would be pleasant. Or a joint. Perhaps I will get back to Spain one day.
"You just do not seem to understand anything at all"
That is a ridiculous statement when I have been involved with practical genetics for most of my life, and studied it at university. You, on the other hand, appear to have had no formal training in the discipline.
"If you want private classes, pay for them".
The evidence is that it is you who requires classes. You seem to have some ridiculous ideas, not realistically related to genetics at all.
"If you want an intellectual buffon for your amusement, pay for that as well".
I haven't needed to pay to comunicate with a buffoon for the last few years. Why should I start paying now? I must confess that you have kept me amused with your adamant stand on incorrect positions.
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