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Category Archives: Occitania

New lactase persistence study rejects "calcium absorption" hypothesis

The “calcium absorption” hypothesis has been proposed as hypothetical mechanism to explain the apparent genetic sweep of lactose persistence alleles in Europe. According to this hypothesis, the possible role of milk in improved calcium absorption would counter the poor vitamin D synthesis in Northern Europe, preventing rickets.
However this hypothesis seems very weak, as I explained recently, notably because bone formation is only one of the various roles of vitamin D and it is probably much more crucial in correct brain development in childhood. Also there is another clear adaptation that actually solves the problem very well: whiter skin able to much more efficiently produce vitamin D in our bodies surfaces by mere exposition to sunlight, a trait that seems to have been increasingly favored after the Neolithic drop in fish consumption (the only actual nutritional source of vitamin D at relevant doses).
This new paper confirms my skepticism.
Oddný Ósk Sverrisdóttir et al., Direct estimates of natural selection in Iberia indicate calcium absorption was not the only driver of lactase persistence in Europe. MBE 2014. Pay per viewLINK  
[doi:10.1093/molbev/msu049]

Abstract


Lactase persistence (LP) is a genetically determined trait whereby the enzyme lactase is expressed throughout adult life. Lactase is necessary for the digestion of lactose – the main carbohydrate in milk – and its production is down-regulated after the weaning period in most humans and all other mammals studied. Several sources of evidence indicate that LP has evolved independently, in different parts of the world over the last 10,000 years, and has been subject to strong natural selection in dairying populations. In Europeans LP is strongly associated with, and probably caused by, a single C to T mutation 13,910bp upstream of the lactase (LCT) gene (-13,910*T). Despite a considerable body of research, the reasons why LP should provide such a strong selective advantage remains poorly understood. In this study we examine one of the most widely cited hypotheses for selection on LP – that fresh milk consumption supplements the poor vitamin D and calcium status of northern Europe’s early farmers (the calcium assimilation hypothesis). We do this by testing for natural selection on -13,910*T using ancient DNA data from the skeletal remains of eight late Neolithic Iberian individuals, whom we would not expect to have poor vitamin D and calcium status because of relatively high incident UVB-light levels. None of the 8 samples successfully typed in the study had the derived T-allele. In addition, we reanalyse published data from French Neolithic remains to both test for population continuity and further examine the evolution of LP in the region. Using simulations that accommodate genetic drift, natural selection, uncertainty in calibrated radiocarbon dates, and sampling error, we find that natural selection is still required to explain the observed increase in allele frequency. We conclude that the calcium assimilation hypothesis is insufficient to explain the spread of lactase persistence in Europe.

The study finds most likely that, most likely, there is population continuity between Neolithic farmers and modern local peoples in Northern Iberia and SE France. Technically they could only not reject this population continuity for all population parameters, but, considering that the same tests strongly reject it for Central Europe and Scandinavia, the most parsimonious conclusion is that some important population continuity does exist in SW Europe since Neolithic. In the words of the researchers:

It thus seems likely that population turnover since or shortly after the Neolithic transition has been less severe in southwestern Europe than in central or northern Europe.

However these ancient populations were lactose intolerant (rs4988235(C)) while modern ones in Northern Iberia are massively able to digest lactose (rs4988235(T)). This supports the theory of adaptive sweep for this allele. 
They suspect that the real reason behind the lactose persistence sweep is caused by basic nutritional reasons (calories and proteins) because milk may have been less subject to fluctuations in crops (traditionally cattle ate grass and not cereals, as happens in modern industrial production, while goats have even more varied natural food sources). In such circumstances episodic famines would have strongly favored lactose tolerant phenotypes, more so if lactose intolerant people would have drank milk or ate high-lactose dairies in desperation, causing them potentially deadly diarrhea.
This is not the same but fits well with my class structure hypothesis, outlined recently. The main reason why I favor this hypothesis is that this generalizing pattern should have affected farmers since very early in the Neolithic, even when they were still living in Asia or Greece, so it is very strange that the genetic sweep only appears since or after the Chalcolithic period, when a hierarchical class society is formed everywhere.

Correction: I wrongly reported the main European lactase persistence SNP as rs13910*T, when it is in fact rs4988235(T)
(already corrected in the text above) This was caused by the
nomenclature used in the Sverrisdóttir paper, where it refers to it as
-13910*T, which must be some other sort of naming convention. Thanks to Can for noticing.

See also:

 

Neolithic and Chalcolithic demographics of Western and Northern Europe

Somehow I missed this important study on the Neolithic and Chalcolithic demographics of Europe, as inferred from the archaeological record (h/t Davidski):
Stephen Shennan et al., Regional population collapse followed initial agriculture booms in mid-Holocene Europe. Nature Communications 2013. Open accessLINK [doi:doi:10.1038/ncomms3486]

Abstract

Following its initial arrival in SE Europe 8,500 years ago agriculture spread throughout the continent, changing food production and consumption patterns and increasing population densities. Here we show that, in contrast to the steady population growth usually assumed, the introduction of agriculture into Europe was followed by a boom-and-bust pattern in the density of regional populations. We demonstrate that summed calibrated radiocarbon date distributions and simulation can be used to test the significance of these demographic booms and busts in the context of uncertainty in the radiocarbon date calibration curve and archaeological sampling. We report these results for Central and Northwest Europe between 8,000 and 4,000 cal. BP and investigate the relationship between these patterns and climate. However, we find no evidence to support a relationship. Our results thus suggest that the demographic patterns may have arisen from endogenous causes, although this remains speculative.

The most interesting aspect is maybe that the (apparent) demographic changes are detailed for many regions of Europe, but first let’s see the general outlook for the whole area surveyed (Western and Northern Europe, Iberia excluded):

Figure 2: SCDPD-inferred population density change 10,000–4,000 cal. BP using all radiocarbon dates in the western Europe database.
Colored arrows and their annotations are mine.

I decided that it was important to mark the main cultural episodes for reference.
1st Neolithic refers to Impressed-Cardium and Linear Band Pottery cultures, which arrived almost simultaneously to Germany and France (of the surveyed areas), although the Rhône-Languedoc Neolithic is a few centuries earlier than the arrow, which has been standardized to 7500 BP.
Atlantic Neolithic refers to the quite belated arrival of Neolithic to Britain, Ireland and Northern Europe (standardized at 6000 BP). This process was quickly followed and tightly associated with the widespread cultural phenomenon of Dolmenic Megalithism. It is most interesting that the main deviation from the pattern of regular growth concentrates in this period and is clearly positive.
Corded Ware culture (Indoeuropean consolidation in Central and Northern Europe) affected only to Germany and Denmark-Scania within the surveyed regions. It was followed by a more widespread subcultural phenomenon known as Bell Beaker, which almost invariably cases manifests within pre-existent locally rooted cultures. Neither seems to be correlated with demographic expansions in the general overview.
Now let’s take a look at the regional graphs:

Figure 3: SCDPD-inferred population density change 8,000–4,000 cal. BP for each sub-region.
Colored arrows, excepted the blue ones (which mark the local first Neolithic), are mine and mark general pan-European initial chronologies (not local!) for Megalithism, Corded Ware and Bell Beaker in those regions where they had some clear influence.

Here we can appreciate that:
Atlantic Neolithic and its associated Megalithic phenomenon are clearly related to notable demographic expansions in Ireland, Scotland, South England, Denmark and Scania. Megalithic influence may also be associated with some more irregular growth in South and Central Germany but rather not in France nor West Germany. A contemporary weak and irregular growth in North Germany (Brandenburg, Mecklemburg and Schlewig-Holstein) may be correlated with Funnelbeaker (with roots in Denmark) and the first Kurgan development of Baalberge and successor cultures (with roots in Eastern Europe), which would eventually evolve into Corded Ware.
Corded Ware only seems related to clear demographic growth in Jutland (and less resolutely in Scania). Bell Beaker is only linked with clear demographic growth in Ireland (and much more weakly in South England and Central Germany), while elsewhere it is rather associated with decline.
For the exact extension of the various regions as defined for this study, see fig. 1 (map).
As provisional conclusion, it seems obvious to my eyes that the most important demographic growth processes were the various Neolithic cultures but that the Atlantic Neolithic (and associated Megalithism) was particularly dynamic. In contrast Indoeuropean-associated cultural phenomena had a much weaker impact, with some localized exceptions, and are generally associated with local demographic decline instead, at least judging from the archaeological record.
See also:
 

Rhône-Provence Bell Beaker

Just a brief note on two French language papers from a decade ago that have shown up in my academia.edu alerts.
The most relevant one because of its wider scope is:
Olivier Lemercier, Muriel Pellissier & Yaramila Tchérémissinoff, Campaniforme et sépultures, au-delà du standard. La place du Campaniforme dans l évolution des sépultures du sud-est de la France au 3e millénaire avant notre ère. Proceedings of the International Conference held at the Cantonal Archaeology Museum (Sion, Switzerland), 2001. → available (with free registration) at academia.edu.

Abstract (only part in English)


Where are the famous Bell Beaker individual burials in the south east of France? What is the nature of the burials wherein we actually find Bell Beaker elements ? And what kind of Bell Beaker is it ? And also : where does the Bell Beakers stand in the evolution of the funeral architectures and rites between the end of the Middle Neolithic and the Early Bronze Age? Answering these questions, thanks to the presence of more than a hundred funeral sites in the area, would change our vision of the Bell Beakers fenomenon itself. These questions are also the occasion to present the diversity and the traditions of the funeral practices by the 3rd millenium BC.

I took some time to read it in spite of my limited skills at French (but it’s still Romance, so well… any educated Romance speaker can read it with some effort) and the overall conclusions are not too surprising: Bell Beaker is not only a burial thing, Bell Beaker appears in burial contexts of older local tradition, etc. 
The details and nuances are many more, of course. On one side the authors discern (much as it happens overall within European Bell Beaker) three groupings: 
  • Corded style in Ardèche
  • International style in the left margins of the Rhône
  • A local variant in the later period
Notice that the authors argue that both the Corded and International styles are roughly contemporary. I can’t judge this but, if real, it may mean a blow against the classical notion of Corded style being older and arriving to SW Europe via the Rhône. 
Another interesting aspect of the paper is that the authors argue for overall continuity of burial styles, which are varied:
  • individual burials with roots in early Neolithic
  • collective burials of both dolmenic-megalithic and cave typology
  • other rarer types, with a handful of examples each
Bell Beaker seems mostly related to collective burials, although in the BB period Megalithism seems to recede somewhat in favor of collective burials in caves, a tradition common in other parts of Europe, especially in the South and SW. This really casts all kind of doubts about BB in this region being able to be explained as some sort of migration from Central Europe (or anywhere else) because, unlike in this Indoeuropeanized area, BB individual burials as such are extremely rare; instead we must talk of BB elements inserted in local traditions of collective or “clannish” nature, just as we can see in Iberia and other Western areas where Indoeuropean influences was still non-existent. 
The other paper is:
Robin Furestier et al., 1974-2004 le site du Fortin-du-Saut (Châteauneuf-les-Martigues, Bouches-du-Rhône) et le Campaniforme 30 ans aprés. Congrès du Centennaire: Un siècle de construction du discours scientifique en Préhistoireavailable at academia.edu (registration needed as well).
This is about a particular Bell Beaker site near Marseilles, whose typology seems mostly influenced by the Portuguese VNSP civilizational center. Otherwise there is other non-BB pottery without decoration and what seems locally rooted stone tools and arrow points.
If you are fluent in French and happen to find out any error in my interpretation, please feel free to correct me in comments, thanks in advance.
 
 

Alert: Foissac cave threatened by pig farm expansion

The expansion of an existent pig farm from 1000 to 8000 heads per annum threatens to contaminate the cave, inhabited in the Chalcolithic and Paleolithic, with pig manure.
Foissac (Aveyron department, Languedoc) is particularly wealthy in burial, pottery and other Chalcolithic remains, which are preserved in situ because of exceptional conservation conditions (it was dug up by F. Rouzaud, M.-A. Garcia and H. Duday between 1978 and 1988). 
More recently (2006) a branch of the same cave was found to have Paleolithic rock art, which would be at risk by this farm. 
There is an ongoing public inquest (ending on September 27) which has been given no publicity. However you may want to write to the authorities at the following address:
Monsieur Le Commissaire Enquêteur
Mairie de Causse et Diège, Loupiac
12 700 CAUSSE ET DIEGE.
There is also an online petition that you may sign.
More information (in French language in principle) at:
Sébastien du Fayet de la Tour : sebastien.dufayet@voila.fr
mobile phone : 06 11 75 97 02
Grotte de Foissac : 05 65 64 60 52

Source: Hominidés.com.
 
 

Another decorated cave discovered in Ardèche

The Ardèche or Ardacha region, so-named for a tributary of the Rhône, is one of the most important and older districts of modern human presence in SW Europe. Its importance was underlined with the discovery of the Grôte Chauvet, the cave of lions.

Now another discovery has been made in the same area with a decoration of what seems to be a horse head. The finding actually was made in 2011 by some speleologist but kept secret till it was researched preliminarily.

Sources[fr]: Pileta, France 3, Paleos Blog.

 
 

Echoes from the Past (Dec 26)

Before the year is over, here there is a bunch of stuff I wanted to mention:
Lower and Middle Paleolithic

Humans may have originated near rivers – Technology & science – Science – LiveScience – msnbc.com – neither savanna nor jungle, beach (river banks) was the favored ecosystem even for old good Ardi, it seems.
Pileta de Prehistoria: 180 prehistoric sites located around Atapuerca[es] – not just Neanderthal ones: a bit of everything (located just outside Burgos city, Atapuerca is a key pass between the Upper Ebro basin and the Northern Iberian Plateau, which must have played an ecological and socio-political role always, and hence attracted people towards it).
Upper Paleolithic and Epipaleolithic 

The boulders at lake Huron were to trap the reindeer (caribou)
Remains found of the culture which inhabited Northern Chile 11,000 years ago – Terrae Antiqvae[es] – they exploited a quartz deposit for their tools in the middle of Atacama desert, which then was probably quite milder.
Simultaneous ice melt in Antarctic and Arctic at the end of the last Ice Age.
Neolithic and Chalcolithic
El Neolítico en Europa: una simulación del proceso | Neolítico de la Península Ibérica – Iberian Neolithic – exposition and criticism in Spanish language of yet another paper simulating the Neolithic ‘colonization’ (Lemmen 2011).

Metal Ages and Historical periods

Iruina blog: doubts about the ability of the Basque Autonomous Police to  analyze the Iruña-Veleia pieces[es] – the Spanish Guardia Civil police force already declared themselves unable to do the tests. The defense asks to send the remains to one of the few international laboratories able to do the tests and has even offered to pay the cost of it. Also at Diario de Noticias de Alava[es].
An intimate look at ancient Rome – OregonLive.com – a journey through the hygienic practices of Ancient Rome.
Scientists unlock the mystery surrounding a tale of shaggy dogs – Native Americans used dog hair for textiles (among other components).
The Archaeology News Network: Real Mayan apocalypse may have been their own fault -overexploitation of the jungle biome caused desertification.

Genetics
Some of these open access papers surely deserved a deeper look at… I did not have time or energies for that however.

  
BBC News – Liking a lie-in in people’s genes, researchers say – long sleeping is a genetic need: tell your boss next time you are late. I am among those who need to sleep 9-10 hours per day (normally) though I have also met people who only sleep 4-5 hours.
The Spittoon » Find Your Inner Neanderthal (I retract what I said before: the results are coherent, even if Africans still get too much too often I guess that’s part of the margin of error. However there is another “free online” genetic test that is misleading).

Biology and psychology
Of mice and men, a common cortical connection – a nice comparison to better understand brain regions. To the right: F/M: frontal/motor cortex, S1: primary somatosensory cortex, A1: primary audtive cortex and V1: primary visual cortex. Mice have a much more developed somatosensory cortex (surely related to whiskers, smell, etc.) but a much less developed frontal/motor cortex (related to willpower and rationality).
Brain Scans Reveal Difference Between Neanderthals and Us | LiveScience – something about the sense of smell, not too clear.

Primates are more resilient than other animals to environmental ups and downs – diversification and flexibility is the key to long-term success.
 

Provenzal genetic data… and weird speculations

The following paper offers some information on the genetics of Provenzals and some specific populations of Turkey (Foça, Izmir) which is compared with older studies (on Turkey and Greece) to reach quite unfathomable conclusions:
I’m split on this paper: on one side it does provide some interesting data and makes some common sense claims (like Provence having been little affected by Neolithic expansion direct colonization) but then you stumble upon absurd ideas, such as Cardium Pottery stemming somehow from “Anatolia”:

Using putative Neolithic Anatolian lineages: J2a-dys445=6, G2a-M406 and J2a1b1-M92 the data predict a 0% Neolithic contribution to Provence from Anatolia.

There is absolutely no reason to be looking at Anatolia: the Neolithic wave that arrived to Provence did not originate in Anatolia but in the Western Balcans. It is very possible that Anatolia was the ultimate origin of Greek Neolithic and this was in turn at the origin of Cardium Pottery Neolithic somehow, but the real origin of the Neolithic wave that arrived to Provence must not be looked for in any case in Western Anatolia – that is a total nonsense.
We know way too little as of yet to explain the exact process of cultural transference from West Asia (Anatolia specially) to the Balcans (Thessaly in particular) and from Thessaly to the Adriatic, where the cultural elements are so distinct anyhow. There is no particular reason to expect any arrival directly from Anatolia into Italy or SW Europe in the Neolithic. Any such migration would have been dampened in two filters: one in Greece and another one in the Adriatic Balcans.
From my ongoing (and slow) work of summarizing  European Neolithic in maps:

Here you can see in brown the first area of Cardium Pottery Neolithic: Dalmatia, Montenegro, Coastal Albania, most of Bosnia, Italy (in a second moment)… It has a precedent in Otzaki (Thessaly) and a derived influence in Biblos (Lebanon) but by no means can it be linked to “West Anatolia” of all possible places.
Universities and grants should require that any geneticist doing historical population genetics hire a prehistorian for assessment, sincerely.
Still there is a very interesting amount of data that is of interest, summarized (as I said before) in figure 2 specially. This is an extensive table that I cannot reproduce here with enough resolution without some previous work. So for reason of its relevance and novelty I’ll focus on the Y-DNA data of Provence (n=51, only attested lineages shown):
  • E1b1b1b1a2 (V13): 4%
  • E1b1b1b1c (M123): 2%
  • G(xG2a3a) (M201): 8%
  • I1 (M253): 2%
  • I2(xI2a2,I2b) (M438): 4%
  • J1 (M497): 2%
  • J2a4h1a (DYS445=6): 8%
  • J2a4b(J2a4b1) (M67): 2%
  • R1a1a (M198): 10%
  • R1b1b2 (M269): 59%
Up 26 to 30% (depending on how you evaluate I2*) of the genetic pool is “Eastern Mediterranean” in Provence. E1b1b1b1a2 (V13) is probably from Albania or other Adriatic areas (see Battaglia 2009). That can also be argued to be the case for all the other “transmediterranean” lineages, which agrees well with a Neolithic origin of all them. However it is not impossible that these Neolithic arrived in batches and with intermediate stops in Italy for example or, why not, in Phocaea in some cases. 
But the research falls very short from demonstrating what they claim to demonstrate. If they have demonstrated something at all they have failed to explain it properly. So the only interest of this paper is the raw data, which adds to other such data to be integrated into a careful and comprehensive exploration of all (and not just some) data with proper prehistoric assessment. 
It is in any case important to understand that under the Neolithic colonization hypothesis, E1b1b1a2 should not be expected to originate neither in Anatolia nor in Greece but in Albania, Montenegro and Dalmatia. And, if anything, in Greece rather than Anatolia. Attributing European Neolithic directly to Anatolia or West Asia in general is not an acceptable assumption but a wacko fetish that should be discarded altogether.