Recent Human Evolution in the house

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Early man ‘couldn’t stomach milk’

Working with scientists from Mainz University in Germany, the UCL team looked for the gene that produces the lactase enzyme in Neolithic skeletons dating between 5480BC and 5000BC.

These are believed to be from some of the earliest farming communities in Europe.

The lactase gene was absent from the DNA extracted from these skeletons, suggesting that these early Europeans would not be tolerant to milk.

The paper will be Absence of the Lactase-Persistence associated allele in early Neolithic Europeans in PNAS. First LCT, then OCA2, and god knows what else? There is a limit in terms of what you can do with archeoDNA, but if the action went down in the last 10,000 years then it isn’t such a sweat.

One thing, the summary in Science is weird. Check it:

The culture-historical hypothesis is that, shortly after the domestication of livestock, a few lucky farmers with a genetic anomaly hit white gold: nourishment via milk. Then, according to this theory, natural selection took over and these lactase-persistent folks proceeded to populate much of Europe with their milk-guzzling offspring. A competing hypothesis argues that ancient Europeans domesticated milk-bearing livestock because lactase persistence was already quite common in certain populations.

Quite common? The area of the genome around LCT was hit by a hammer blow of selection less than 10,000 years ago, that’s why researchers use it to check if their methods for detecting selection are working. The fact that independent events of lactase persistence exist among other populations via alternative genetic architectures seems to indicate clearly the power of gene-culture coevolution. What’s up with Science doing a “look at both sides” framework when the evidence is so lopsided? I suppose selection could have been induced by a causative factor aside from milk, but I think we’re verging into Humean skepticism at this point, denying the ability to discern causality at all….

Carl Zimmer has much more….

Related: Lactose tolerance by a different stroke. Lactose tolerance/intolerance. Are multiple lactose tolerance mutations surprising? Genes & culture & milk. Lactose tolerance, is it “dominant”? Milk digestion, it does a body good.

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11 Comments

  1. Razib, could you spell this out for those of us who come here mainly to learn something (rather than read a rant)? The sentences “First LCT, then…” and the paragraph starting “Quite common?…” seem to presuppose understanding of a broader picture, and some agreement of mine with a conclusion that I am sure is obvious to you, but where I frankly don’t even understand the dichotomy.

  2. arbor, i’m just saying that scientists will start mining the subfossil material that might have dna for all sorts of loci of interest to document recent evolution. in mean, before one had to infer the change in allele frequencies over time, and time intervals were huge. now they can get data points which nail down things more clearly. the paper itself uses 8 individuals i believe, so it isn’t like this a big data set. but, in northern europeans the allele in question is about 90% in frequency, so what are the chances that none of the 8 individuals would carry the lactase persistant LCT variant???? i get 1 in 10 million assuming that allz indepedent.

  3. just to be more precise, scientists have been using fossils to calibrate phylogenies before. this couldn’t be done with allele frequencies on traits which don’t have an outward affect. but with the advances in extracting and amplifying ancient DNA now traits which don’t leave an impact on skeletal morphology, etc., can be calibrated with greater precision. morphologically modern homo sapiens predates behavorially modern homo sapiens. we assume from the material culture that post-ice age man 10000 years BP was ‘just like us.’ aside from their greater average size they aren’t that different morphologically. but, examination of the genetic material could turn up lots of differences. e.g., there is already evidence that europeans and east asians were dark skinned 10000 years ago. but there might have been changes in personality to accommodate dense living too….

  4. What is the ancestry of the eight individuals? Are they from the small numbers of migrants who are thought to have brought agriculture to Europe from the Near East in the Neolithic? Is this implied? The BBC and Science articles don’t mention this fact.

  5. Just google: Ural farmers got milk first . There was a study back in 2004 that concluded: lactose tolerance first appeared at Ural-area farming population 6000 kya.

  6. Right, but these individuals were lactose intolerant; therefore, not part of that group. 
     
    My point is that the sample may not be representative of the Neolithic population in Europe if early farming communities were distinct.

  7. Are they from the small numbers of migrants who are thought to have brought agriculture to Europe from the Near East in the Neolithic? 
     
    i believe the individuals were from disparate locations across northern europe.

  8. The early dairy cultures seem to radiate from Schleswig-Holstein – so I hope this sample included Neolithics from this core area?!

  9. There is also an interesting article in New Scientist that suggests a Dairy diet increases fertility – though the results are less than conclusive??!!

  10. It seems to me that cattle must have been domesticated for centuries before they were docile enough that a sane person would dare attempt to milk them.  
     
    You can get buffalo milk from the pacifistic Indian water buffalo, but nobody tries to milk a violent imperialistic American buffalo (bison).

  11. You can get buffalo milk from the pacifistic Indian water buffalo, but nobody tries to milk a violent imperialistic American buffalo (bison). 
     
    chauvinist ;)

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