Tuesday, November 18, 2014

The Known Knowns and No-no's

Here's a quick review on the new paper "The Known Knowns and Known Unknowns"

Don't misunderstand.  Large parts of the paper are largely agreeable.  Actually, the Brandt crew has smartly navigated some treacherous waters and diplomatically questioned some of the more questionable studies.  However, some of the genetic studies coming out of SW Europe that this paper references are either too old or sucked.  This is hugely problematic for Beaker studies since the phenomenon is mostly accepted as having spread from this region.

From the paper:

If we followed the logic above, then the U haplotypes could likely be interpreted as a Mesolithic legacy.  However, the situation is more difficult to decipher in the case of haplogroup H, which has not been observed in Mesolithic Central Europe and Scandinavia but is present in Iberian huntergatherers (as shown above)
Let me put it succinctly.  Haplogroup H did not expand into Mesolithic Europe from Iberia because it wasn't in Iberia in the first place.  See my last post on the shellmiddens and then take a close look at the contexts of La Chora and La Pasiega.  The nominal typing of any of Hervella's H remains is questionable.  It is a very weak link.

Most of the subgroups in present-day Europe show late glacial or post-glacial coalescence dates, arguing for a re-expansion during the major warming phases after 15 kya (Achilli et al., 2004; Pereira et al., 2005; Soares et al., 2010).Subgroups H1, H3, and H5 are believed to have spread from a Western refugium in Franco-Cantabria based on largely overlapping dates (11.1 kya, 11.5 kya, 13.9 kya, respectively) (Soares et al., 2010) and the fact that these are the most common types in Western Europe.
I'm not sure how the coalescence ages of H1, H3 and H5 help the thin notion that these expanded from a LGM refuge in Iberia.  In fact, when you further break these clades into their subclades, not only are they too young (Loogvali, 2004 & Roostalu et al, 2007) but all three are present within archaeological contexts of the ancient Near East of the early Pottery Neolithic. 

What kind of convoluted logic gets us immediately from the Near East to Iberia where it doesn't expand, but then does expand to its original home via some unknown route, waits, then explodes like a pinata over Russia, Siberia and the rest of Europe?

While haplogroup H has been reported from Iberian Mesolithic individuals, the typing resolution unfortunately does not provide an unambiguous assignment to any of these subgroups (Chandler et al., 2005; Hervella et al., 2012).
Not that this ever mattered to begin with.  Regardless of the typing, the provenance and age of the remains selected by Chandler or Hervella were very tenuous to begin with.  See my last post on the middens.  I haven't got to Hervella yet, that will be another hour long post, but while Hervella's results are often cited, few have taken the time to look at situation surrounding the stuff being shoveled out of La Chora and La Pasiega.

However, all Middle Neolithic individuals from Treilles in Southern France could be assigned to subgroups H1 and H3 via coding region SNP typing (Lacan et al., 2011b).
Firstly, the Treilles individuals were Late Neolithic, not Middle Neolithic, and further came from the very cusp of the Chalcolithic.  With this was a host of technological changes creeping from the Eastern coast of Iberia along the Mediterranean coast of France as far as the Po Valley.  The Los Millares, Treilles and Remedello-I cultural changes reflect significant changes in the material culture of those regions.  Rather than the Treilles mtdna lines being native, it is equally possible that the combination of H1, H3, H5 and Haplogroup I pairings reflect an immigrant population from, say, nearby Sardinia. 

Taken together, this suggests that genetic elements of the ‘Neolithic package’, which had reached Central Europe via the Continental route (event A), also arrived in Southwest Europe through the Mediterranean route (Fig. 3A). However, the huntergatherer legacy is more dominant in the Iberian Neolithic compared with Central Europe, indicating a Neolithic transition with a larger contribution of the indigenous population [in Iberia] combined with a reduced impact of early farmers.
The Iberian Mesolithic almost completely imploded into a period of "archaeological silence", as described by Cortes-Sanchez (2012) while referring to Northeastern Spain.  (The same is true for the Mesetas, and with the exception of the Pyrenees, there's not much hope to believe in the prosperity of La Brana and his ilk in the Northwest of Iberia.

In fact, there isn't much reason to believe that Mesolithic Iberians fared well at all with the onslaught of Neolithic farmer immigration coming from three directions, not that they didn't already have problems with what Cortes-Sanchez called their "subsistence crisis".

My rant here is to draw attention to cards at the bottom of the house of cards.  There have been a lot of assumptions about ancient European DNA over the years that were built off of previous assumptions.  All I'm saying is that we need a solid foundation built on recent, high-resolution studies on remains that are invincibly provenanced.


  1. "What kind of convoluted logic gets us immediately from the Near East to Iberia where it doesn't expand, but then does expand to its original home via some unknown route, waits, then explodes like a pinata over Russia, Siberia and the rest of Europe?"

    The simplest explanation would be that "Basal" existed across a wide range as HGs before one segment became farmers. In which case when Basal farmers arrived in areas with Basal HGs there wasn't much genetic change apart from any specific advantageous genes the farmers carried.

    The farmers must have been HGs before they became farmers so I find it really odd that people think it's likely that the farmers developed out of a completely distinctly and separate group of Basal HGs.

    This does imply there were two sets of HGs - Basal ones in the African Border Zone and a second more northern and eastern set. This might fit with an expansion of ASE people similar to Ust-Ishim coming out of S/SE Asia which initially diverted around the African Border Zone populations on their way into Europe.

    So the answer to your question might be:
    1) they didn't arrive immediately from the near east, Basal HGs were already in Iberia when Basal farmers arrived
    2) they didn't expand because they had ASE pressing down on them from the north easterly direction
    3) they expanded later with BB because by then they had the advantage

    Also if this model is correct and there was both HG mdna H and farmer mdna H it might have been the farmer version that spread.

    Like I said in the previous post I think it is quite possible this H is solely farmer mdna and the provenance is wrong or that the provenance is correct but the HG version of H was replaced by the farmer version of H but at the same time I think it is extremely unlikely that the Basal HGs which must have existed before Basal farmers didn't live all round the Med and up the Atlantic coast *before* the spread of the Basal farmers.

    1. I agree with what your saying about the simplistic view of haplogroups. In this case its the estimated coalescent age of H1-H5 and its diversity that make the LGM Iberian refuge a hard sell.

      you'd think that that after x-thousand years you'd have a fairly evenly mixed Iberian refuge population that recolonized the continent. But as the Brandt paper mentions (and Brother ton) H is conspicuously absent in the continent in the Mesolithic.

      Having said that, I'd agree the low H population was likely farmer like, at least more like a Capsian farmer

  2. I agree completely that the claims of mesolithic H in Iberia ain't worth anything, but there is reasonable evidence that some of haplogroup H in Central Europe may have come from Neolithic(!) Iberia, as discussed in detail in this earlier author-overlap paper:


    Even taking the conclusions of that paper, they should have had fewer question-marks on the H coming from the east, since that paper claims that H1 and H3 are from Iberia, but other H groups (H2a, H7, H11) have "genetic affinities to the East", by which they mean to modern samples to the East, with all the possible pitfalls of that, but hey...

    1. I think the Brotherton paradigm continues to be validated with a growing stack of results from around Europe.

      They view what I call "super-H's" coming from the Danubian and Cardial farmers as part of the typical "Byblian maternal profile" which includes items like N, K1, X2, W, T2b, etc, etc. Although these also included H1 and H5a, etc, the decline of total Byblian percentages is so steep that its hard to know how much of these high frequency haplogroups having continuity to the Neolithic.

      Of course, the fact that they build off Chandler and Hervella don't make the Brotherton conclusions wrong. I think they are largely correct as viewing an Iberian expansion for the low H's. How and when these ended up in Iberia is an open ended question.

  3. @ BellBeaker Blogger and Others
    Would You and Other guys like to take part in this Great Discussion?
    Good Day.