Tuesday, November 10, 2015

Another Pig Study

Another volley in the pig domestication war continues...

Now we have this study on pigs of the Biarzo shelter in Italy, where the authors suggest that the mtdna evidence could suggest pig domestication was a continuous, native process to Europe from the Mesolithic, not necessarily the chattel of farmers from the Near East.  (Their position seems more nuanced than this, but basically that's the gist)


Wild boar are wanderers unlike most vertebrates and don't have a particular routine, territory or migratory route.  This fluidity makes genetic phylogeny-geography analyses a little shaky IMO, never mind that pigs are the most prolific mammal of its size.  I think because of this, you may get results such as:
"We found that a rapid mitochondrial DNA turnover occurred during the Mesolithic, suggesting that substantial changes in the composition of pig mitochondrial lineages can occur naturally across few millennia independently of domestication processes.  Moreover, so-called Near Eastern haplotypes were present here at least two millennia before the arrival of Neolithic package in the same area."
And then sitting up in the coffin he began speaking:
"Consequently, we recommend a re-evaluation of the previous idea that Neolithic farmers introduced pigs domesticated in the Near East, and that Mesolithic communities acquired domestic pigs via cultural exchanges, to include the possibility of a more parsimonious hypothesis of local domestication in Europe."
Sorry, I'm very cynical on the existence of Islands of Excellence.  I don't see anything worthy of parsimonious treatment either.  Certainly there were intellectually curious individuals 50,000 or 100,000 years ago.  Why didn't they domesticate the boar if domesticating the boar is both beneficial and obvious?  Maybe that's because a lot of this comes down to culture and economics, like that of the ancient Near East, and not that of heathen, spear-chucker hunters. [See Also]
A sounder eating BBB's corn!
"...Larson in two seminal papers10,35, affirms that pigs domesticated in the Near East were introduced into Europe..., but that soon after the genetic legacy of these pigs and their descendants were lost due to constant hybridization with European wild boars, replacement by pigs domesticated in Europe, or both. This hypothesis is based on two pillars: 1) temporal changes of mtDNA lineages in Europe are related to domestication, and 2) NE-Y mtDNA lineages appearing and then disappearing in some sites in Europe are genetic markers of Near Eastern domestic pigs. Clearly, our main results shake these pillars."
Fair enough.  Also, they make reference to a recent paper by Evin et al, 2015 (Ref 40 in the paper) showing a clear East-West division in the dental morphology of boars with Europe/North Africa on a western side and Russia/Near East on the other.  (In the above graphic you see essentially crosses between feral hogs and Russian boars)

Back to the pillars of parsimony.  Parsimony is savages domesticating the pig a hundred thousand years ago in Europe.  I'm being facetious, but seriously, if it is so self-evident to a hunter-gatherer to stockade a wild boar, then why wait?  The simplest explanation is that the husbandry here was done by husbandmen, with fences, knowledge, social structures, economies, etc.  I'll be satisfied to be proved wrong.

A somewhat related topic..


One interesting subject is the abhorrence to pork in the modern Middle East, which is sort of ironic given that this is likely where the pig was domesticated.  

The change in attitudes to pork appears to have been a slow process, first in the polytheistic religions and then followed by Judaism.  I came across Chapter 2 of this book: Eat Not This Flesh by Frederick J. Simoons (free via ebook) 
 

Vai, S. et al. The Biarzo case in northern Italy: is the temporal dynamic of swine mitochondrial DNA lineages in Europe related to domestication? Sci. Rep. 5, 16514; doi: 10.1038/srep16514 (2015). [link]

7 comments:

  1. One of the pillars of domestication is the form of a domesticated subtype with domestic human selected traits relative to the wild type. Just as cultivation of wild type crops is mere proto-farming, husbandry of wild type animals is mere proto-husbandry. I wouldn't be surprised if there were some Mesolithic communities with rabbit warrens in which wild type bunnies were kept for food, and maybe even some ad hoc pens for wild boars that were captured and kept for short periods of time before being eaten. But, I don't think that the Mesolithic people tried to domesticate the wild boar through selective breeding or succeeded in doing so. And, I think it is very likely that domesticated pigs are significantly different in important phenotypes from wild type boars.

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    1. I think you're right. Capturing, training or managing a wild animal (raptors, honeybees, reindeer, fishing ducks) is a lot different from improving an animal's shape through breeding, particularly the more difficult early stages.
      This more advanced understanding isn't necessarily intuitive, IMO, and requires a level of sophistication and effort that better fits farmers who did this numerous times with plants and animals.
      I welcome their evidence and they do have a good point as it invalidates previous supporting arguments, however I disagree with the plausibility of native domestication..

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    2. My understanding is that whether you're talking about animals or plant cultivars, selective breeding is not the most common understanding of how phenotypes changed under early domestication. Instead, these would have been traits that happened more or less automatically under domestication. If you're attempting to harvest a crop and then use some of the seed the next year, you're going to have more luck gathering those seeds that cling to the stalk longest, and only fall off when you shake it. Those seeds are most likely to be planted. Soon, you've accidentally "selected" for a new phenotype. It was likely many generations after domestication that people began to realize you could selectively breed with intention.

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    3. Ryan, I agree mostly with what you've said, but taken a step too far you could say that AMH involvement with any plant or animal would always accidentally lead to either domestication or improved phenotypes.
      I'm not against this notion but I would draw a line with true livestock in the Neolithic. But of course it's all theoretical for now.

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  2. I think the pork abhorrence was due to a tribe's totem being the wild boar, particularly the Oroan/'Kurukh a non-Hindu people of Eastern India who historically travelled from the west. Canaanites raised pigs, Hebrews didn't as far as I recall.

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    1. Kees's hypothesis was somewhat similar to your totem (cited in the book above) basically that in predynastic Egypt; the conquered delta Egyptians associated with Set which the highland Horus-worshippping Egyptians detested (the people). The beast (in Kees's view) became increasingly demonized in Egyptian religion.

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    2. I have seen academic literature (but can't find a reference right off) dating the pork taboo in the Near East to the 4.2ky event.

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