Wednesday, September 21, 2016

Sexual Dimorphism of Bell Beaker Folk (and VanderWaals, 1984)

In the previous post "Being Tall" the historic purpose of swaddling infants in North Eurasia was explored and its likely use among the prehistoric Bell Beaker groups for the purpose of improving stature and form.

Beaker Mother and Infant, Camino de Yeseras (Foto a partir
de Blasco et al. 2005: Fig. 7)
There is still yet another interesting aspect when looking at the circumstantial clues pointing to the practice among early Beakers.  That is that boys appear to have been more often swaddled than girls, and by a fairly large margin if you were to accept the hypothesis that flattened occiputs are evidence of this practice.   (This by the way has been demonstrated in studies from Kurdistan to Mongolia)

Here's a long excerpt from a 1984 paper by Van der Waals, but the context is important:

In his paper 'Anthropology of Bell Beaker people', presented to the symposium, Professor Kurt Gerhardt summarized and substantiated his views on Bell Beaker physical anthropology (1976).  Gerhardt is a representative of the traditional typological approach in physical anthropology, with a keen knowledge of human genetics. He acquired fame by his definition of one specific cranial type, occurring in Bell Beaker contexts: the planoccipital steephead. At Oberried he pointed out that this planoccipital steephead was the most characteristic and numerically important type identified by him among the essentially heterogeneous complex of cranial types in Bell Beaker graves. The type had
never been found with any of the earlier Neolithic Central European groups. He based his arguments on his own research, chiefly comprising finds from Central Europe (from the Elsass to Southwest Poland), but on the basis of inspection of material published and illustrated in Crania Britannica from 1865 he was convinced that planoccipital steepheads were also represented on the British Isles. What made Gerhardt's contribution remarkable was his emphatic demonstration of a systematic sexual dimorphism. Among male 'Bell Beaker' skeletons in Central Europe, he had found more than twice the number of planoccipital steepheads than among female 'Bell Beaker' skeletons of the same area.  He furthermore noted that many of the male planoccipital steepheads had been found in the richer Bell Beaker graves, and concluded that 'this remarkable situation asked for a sociological explanation'. During the final discussion of the symposium he explained that he could only think of this situation as resulting from strong endogamy within clans, as with Medieval European high nobility. The resolution of such a social system at the end of the Bell Beaker period could account for the disappearance of the planoccipital steephead in the succeeding Unetice period.

Essentially we learn something that has been recently eluded to in Liesau et al, 2015, and that is a sociological dimension in which head shape is loosely associated with status.  In Camino de Yeseras, the flat-head mother lived a good life and was given a rich burial.  Ordinary women buried nearby lived hard lives and had modest burials.

The other aspect is the attention or preference given to the development of boys.  Throughout much of the Old World, especially the modern MENA nations, boys are nursed substantially longer than girls.  In fact, the attention disparity between genders can be cruelly stark.  The degree to which girls were swaddled compared to boys may depend on where Beaker girls fell within the sequence of male children as parents would focus attention and resources on their boys.

An interesting point to dove-tail in a later post is the apparent 'ruggedness' of Bell Beaker males.  Aside from being taller, they are also much stronger with stronger bones and stronger muscle attachments.  Obviously part of this is genetic, part of it is diet, but another aspect could be environmental.  In other words some of the skeletal evidence may point to resistance training, or at least 'feats of strength', among the warrior elite.  Back to Van der Waals:

In comparing the complete groups of the three periods Czarnetzki demonstrates that the
greatest divergence is between the Late Neolithic (=Corded Ware) and Bell Beaker groups, the smallest between Bell Beaker and Unetice groups, the divergence between Late Neolithic and Unetice being intermediate. The same pattern of divergences emerged when male individuals only were taken into consideration, but among females the divergence between Late Neolithic and the Bell Beaker period was smaller than between the late Neolithic and Unetice. In this case, there appeared to be a normal type of increase in divergence through time. In other words, the gene pool in females remained unchanged into Bell Beaker times, only then certain changes appeared to take place. During the Bell Beaker period, the introduction of a new gene flow must be inferred from the shift in the values active in the formation of epigenetic traits, a shift caused
mainly by male individuals.
Here's the irony of all of this:  everything is circular, from the Dutch hypothesis to Clarke's social continuity.  To be overly cavalier in dismissing a particular theory is to miss that often times there is a valid argument to be made, although maybe not an all encompassing explanation.  I do believe that catastrophic population changes are occurring at the end of the Neolithic, but Clarke's points aren't without merit.  Some of the skeletal quirks of Beakers could in fact be environmentally and culturally induced from the Early Bronze Age arms race:
Yet, to many of the participants the elements of convergence in the presentations of Gerhardt and Shennan were quite intriguing. David Clarke then intervened and pointed out that the convergence of ideas was only apparent. 'There is in fact a very basic division between us here', Clarke said. The question of origins . . . is part of the
questions asked by the old school, about how, when and where. The questions of greater interest and deeper explanatory meaning answer the questions why'. Clarke went on to make clear why he had a deep mistrust of all physical anthropological evidence. If I remember correctly he said it was because the skeletal material available was too much the result of heavily biasing regional circumstances, and therefore liable to generate illusory conclusions.

See also [here]



"Discontinuity, cultural evolution and the historic event"
J D VanderWaals, Proc SocAntiq Scot, 114 (1984), 1-14 [Link]

SUMMARY
Aspects of the traditional culture concept, the closely connected twin concepts of continuity
and discontinuity, and their usefulness for prehistory are reconsidered. Continuity and discontinuity
are considered as functions of the evolution of culture; it is argued that the role of the historic
element should not be overlooked.

4 comments:

  1. * "In comparing the complete groups of the three periods Czarnetzki demonstrates that the
    greatest divergence is between the Late Neolithic (=Corded Ware) and Bell Beaker groups, the smallest between Bell Beaker and Unetice groups"

    This supports that conclusion that Bell Beaker is not derived from the Corded Ware culture (which was indisputably linguistically Indo-European), consistent with my hypothesis that the Bell Beaker culture was not linguistically Indo-European. It is also consistent with a my hypothesis that the Bell Beaker to Unetice transition involved a likely language shift from the Bell Beaker culture language to an Indo-European Unetice language via elite dominance with only minor demic impact.

    * Your post also offers evidence consistent with the hypothesis that elites in Bell Beaker society were endogamous and that this norm collapsed when Bell Beaker elites lost their status because they were replaced by a thin layer of Unetice elites (who may not have maintained elite endogamy to the same degree). This is how and when I think that almost all of the people with Bell Beaker ancestry in Europe came to speak Indo-European languages.

    * Finally, I am also impressed by the suggestive evidence in this post both from the cranial data and the robustness of Bell Beaker elite men, that the Bell Beaker people were comfortable making pretty harsh distinctions between the people in their realms on the basis of gender within their own families, and between elite families and the rest of the people, that were severe enough to have effects that show up in physical anthropology.

    This, together with their endogamy practices, can help to explain why the lactose tolerance gene, which went from extremely rare to predominant during the Bell Beaker period in Western Europe in one of the starkest examples of fitness based selection in known human genetic history, had such an outsized impact on the gene pool relative to the known functional benefits of the gene. One can imagine a narrative in which the gene's spread was largely confined to Bell Beaker elites due to endogamy practices and elite interaction at long distances which the great expanse of the Bell Beaker territory made possible. Then, one can imagine that Bell Beaker elites had an incredibly outsized impact on the future gene pools of Europeans in former Bell Beaker territories, not just because the lactose tolerance gene provided a modest intrinsic fitness advantage to those elites, but also because the Bell Beaker elites were quite comfortable favoring their male children in times of nutritional scarcity at the expense of everyone else in the community including all but the most elite of their daughters, that would have gone far beyond adults drinking milk to decisions about who got limited food supplies period. Thus, it makes a pretty good case that the lactose tolerance gene became so common in the former Bell Beaker territory not just because it intrinsically conferred fitness (although it surely did which allowed it to become predominant within Bell Beaker elites over 1000 years or so) but also because it was ancestry informative of a population who benefitted from cultural/political fitness relative to their fellow community members with they exploited ruthlessly.

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    Replies
    1. It'll be interesting to see in future studies how the frequency of LP changes during this period. Some traits, especially recessive traits, do such endogamy as you suggest. Perhaps endogamy among geographically distant but closely related groups.

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  2. Andrew
    If genetics underlie, at least in part, this high stature in BBC, then doesn't it further support an "eastern" origin for the BB males rather than Neolithic Iberian ?

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  3. Interesting article. I wonder how healthy Corded Ware females were? In a society that favored males and considering CWC were highly mobile, I think their health would be poor.

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