Friday, February 5, 2016

The Sad Case of the Orthodoxy and the Posth Article on Pleistocene Demographics

Just a couple months ago, in the context of the peopling of Ireland, I emphasized on Eupeida (and here) how important it is to put all the Theories Du Jour that are based on modern uniparental distributions through a model based on population demographics and sound logic.

Specifically, I emphasized that ancient population sizes were minuscule compared to modern ones, and that if a population started a long long time ago, with a size that was way way small -- compared to subsequent waves -- that it would give a false signal that the original population was "conquered" or "outcompeted" or "never existed" or originated somewhere incorrect.   I cautioned against those four errors.  


This engendered quite the debate on Eupedia forums.  When backed into a corner and shown the weakness of his "R1b Were Studly Conquerors Theory," the "blindly following the current orthodoxy" folks react badly.
 

Many "Interwebz Scientistz" fail to grasp these concepts.  They favor their own wacky, biased theories based on what they see today only.  If a land is populated by one people, they must be all conquering studs, right?

Today, Posth et. al put out an extensive paper on Pleistocene demographics.  


Its shocking discovery?  Just like Y DNA Hg C existed in Europe in tiny numbers among the very first Europeans, so did mtDNA Hg M.

M disappeared eventually, due to the simple fact that its initial population size was tiny, and that because it had been there so long, the odds that certain women didn't have daughters, each generation, eventually meant it was not passed on.  Remember, we're talking uniparental markers here.  

The authors commented exactly as I did: up to now, people mistakenly believed that Hg M never set foot in Europe -- or that if it did, it was killed off or whatever by a new wave.  Sorry, both theories are wrong.

It is WONDERFUL to see another peer-reviewed, scholarly paper making this exact same point, and backing it up with newfound data.

As the paper indicates:

-These first hunter gatherers started with a TINY initial population size.

-There is a loss every generation of males having males or females having female offspring.

-I've calculated the approximate odds of a male not having a male child or a female not having a female child (i.e. looking like their uniparental marker was "conquered") at 12.5%, each generation, totally random.

-The longer a population has existed in a locale (and being free of mutations), the more generations go by, the greater the chance that random happenstance, chance, etc. will make it appear that a Hg either never existed or was slaughtered in a mass killing/enslavement/mate preference.

Now you have further proof of it.

I'm waiting to hear how Hg M died out because of some studly new more beautiful females who moved in.  Oh woops, Maciamo doesn't post here.  And he doesn't himself bear Hg M.  And M is not linked to R1b...

13 comments:

  1. Have you not noticed that the initial summary states that the mitochondrial haplogroup M is found in Native Americans. Furthermore it later states that mtdna haplogroup N is also found in Native Americans. As far as I am aware Native Americans populations have only been recorded with mtdna haplogroups A, B, C, D and X. So where did the mtdna haplogroups M and N come from? NeilB

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    1. Do some reading before you post anything. mtDNA haplogroups A, B and X descend from mtDNA macrohaplogroup N and mtDNA haplogroups C and D descend from mtDNA macrohaplogroup M. This is basic knowledge in genetics.

      https://en.wikipedia.org/wiki/Human_mitochondrial_DNA_haplogroup

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    2. Thank you for your reply, of course I know which, haplogroups A, B, C, D and X descend from. However the way the paper states: " We unexpectedly find mtDNA lineage M in individuals prior to the Last Glacial Maximum (LGM). This lineage is absent in contemporary Europeans, although it is found at high frequency in modern Asians, Australasians, and Native Americans.". Further on the paper states " However, whereas present-day Asians, Australasians, and Native Americans carry both M and N mtDNA hgs,..". Are you therefore saying the paper lacks clarity and should read Native Americans have haplogroups derived from mtdnas M and N? To me as a science graduate the paper's wording indicates mtdna M and N are found in Native Americans. The condescending tone of your reply was uncalled for by the way. One only has to look back a few years to the discovery of haplogroup X in the Americas and its use by various fringe groups with racial agendas to suggest that north America was peopled by Europeans to see that lack of clarity is a dangerous thing. The Rasmussen et al paper from 2014 finally put paid to that. However silly stuff still appears on the net! A review paper was published only last October ( Raff and Bolnick 2015) refuting the idea in a more accessible way. I hope you appreciate my point.
      Lastly mtdna haplogroup M has been found in an ancient burial at China Lake (Malhi 2007), thus making the statement in the Posth paper partially correct. I suggest the authors should have used the phrase "and haplogroups derived from mtdna M and N in Native Americans". I'll say it again: lack of clarity can cause serious, unforeseen, long term consequences in terms of public perceptions of science. NeilB

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    4. There is no lack of clarity. Their statements make it clear that in M and N they include all of the haplogroups derived from them. The sentences "This lineage is absent in contemporary Europeans, although it is found at high frequency in modern Asians, Australasians, and Native Americans" and "However, whereas present-day Asians, Australasians, and Native Americans carry both M and N mtDNA hgs..." make it all pretty clear.

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    5. You have missed the main points of my argument. The phrasing of the sentences from the Posth paper ARE ambiguous. The poorly written sentences lacking clarity are: " We unexpectedly find mtDNA lineage M in individuals prior to the Last Glacial Maximum (LGM). This lineage is absent in contemporary Europeans, although it is found at high frequency in modern Asians, Australasians, and Native Americans.". AND " However, whereas present-day Asians, Australasians, and Native Americans carry both M and N mtDNA hgs,.." IF you had argued that "lineage" in sentence 1 and "hgs" in sentence 2 were meant to encompass the derived Native American haplogroups A, B, C, D and X I could have agreed with you. However ignoring the wider public context of how such sentences MAY be read by the broad range of people from less scientifically literate backgrounds is an error on your part and I believe on the part of the authors. As you yourself said on the 13th of December 2015
      " I think if we purport to be scientific, we need to speak with scientific precision."
      As to your ignoring parts of my argument, you also once said
      "But they ignore the lack of samples when convenient, if it doesn't fit in their narrative for that time or place."
      Perhaps I could paraphrase you as saying "But I'll ignore some points of your argument when convenient as they don't fit in with my narrative for this paper". NeilB

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    6. As you yourself said on the 13th of December 2015
      " I think if we purport to be scientific, we need to speak with scientific precision."
      As to your ignoring parts of my argument, you also once said
      "But they ignore the lack of samples when convenient, if it doesn't fit in their narrative for that time or place."


      They are not my sentences, they are mooreisbetter's sentences, so again: Do some reading before you post anything.

      As for the rest of your post, I already posted my reply about those points.

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    7. This has been an unproductive exchange. What have I learnt?

      1. Mooreisbetter = Onur

      2. Onur/Mooreisbetter does not
      enter into discussion he only states opinions

      For more on Onur check out this:
      http://www.unz.com/comments/akarlin/poland-can-into-putinization/

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    8. No, you fool, neither mooreisbetter nor that Onur you see on that unz.com page is me. If you look at the comments section of this Eurogenes thread, you can easily see that I debated with mooreisbetter in the past and hence I am not him.

      http://eurogenes.blogspot.com.tr/2016/01/the-enigmatic-headless-romans-from-york.html

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    9. Sorry not falling for that one, several of these genetics blogs have 'stalking horse' personalities that are just the blogger him/herself. You 'two'are ONE of those!
      Sorry I had to out you but you were so unscientific in your unreasonable approach to actually discussing the points I raised in my original post that the conclusion became obvious.

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    11. @NeilB

      You use dirty tactics of defamation just because I revealed your error. Your behavior is unmanly and dishonest.

      @mooreisbetter

      I warn you about this NeilB guy. He is slandering us both. I do not know what you are planning to do, but I am considering suing him for libel.

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  2. Some interpretations of Paleolithic Europe estimate as little population as a few thousands, even barely above the 1000 figure. I think that is ridiculous, considering that for example the Hadza are in those figures while occupying a much much smaller territory. Also I estimate that each "district" (my archetype is a well studied one in West Biscay and Eastern Cantabria) would feed a "clan" of some 100 people at least. If so, we go into the many thousands only for the Franco Cantabrian region very quickly, at least one thousand just in the Cantabrian strip of Northern Spain. Obviously, in many eco-niches at least, farmers could support even larger populations and in any case their pressure for the land would gradually force the hunter-gatherers into assimilate or face big problems, but the differences in density were not as extreme as often purported.

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