Man is more than one tree

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This is a short post which I will elaborate on later in a broader biological context, but Richard Sharpe’s comment is something I want to respond to real quick: “If Greeks are Caucasian, then…Just how do you designate yourself….”

First, I’m not white, my ass is a rich brown, ergo, I’m not “Caucasian.” The nerdy amongst us though might be familiar with the term “Caucasoid,” which shares a relationship with Caucasian (there were very few non-white Caucasian/Caucasoids in the country when these terms became common). Well, operationally I don’t think South Asians should really be considered Caucasoid (though Middle Easterners should, Middle Easterners-Europeans are a monophyletic clade in relation to Brownoids). On a phylogenetic tree, if I had to make one, I would make Caucasoids and Brownoids (my term) a monophyletic clade in relation to other races of man.

But there’s a serious problem with this in my opinion. In The Real Eve Stephen Oppenheimer spun a grand genetic-historical narrative which culminated during the Last Glacial Maximum, about 30,000 years ago. It is from this point that Oppenheimer traces the origins of modern races. He states flat out that admixture has been minimal. Perhaps. Perhaps not. The problem with Oppenheimer’s story is that it is rooted in mtDNA, which is passed only through the female line. This is neat, because it eliminates recombination between lineages, so you get a clean cladistic tree all the way back to a common ancestor with all the putative ancestral character states. But the vast majority of our DNA is recombinant, and not passed uniparentally. You look at many Latin Americans, and the mtDNA will tell you they are cousins to East Asians, while the NRY (passed through fathers) will tell you they are Iberians. This is the most extreme case, but I doubt it is the only one.

So back to Richard’s question. The problem I have with answering stuff like this is that I’m a melange, as all people are. I can say that I suspect it is likely that vast majority of my ancestry can probably be traced to the South Asian subcontinent around 10,000 years ago, but my NRY and mtDNA might say something different. Our full ancestral complement does not decompose itself into a bushy cladistic tree, it a reticulated mish-mash, like a ball of spaghetti. I mean, we’re not asexual, right? We’re one species across which genes can flow in a sweeps. Well, tell that to the authors that are making tidy advances based on books that pedal neutral lineage markers as the family-tree writ large. Genealogy is big bucks, even in quasi-scientific garb.

And who forgot selection? (Natural and social)

P.S. I have to say, about 2/3 of my scientific posts probably are derived from a question from the comment boards. A lot of the time it is even a 2nd or 3rd order idea, not a direct response. So thanks.

18 Comments

  1. My daughters are both half Chinese (south-western Han) and half Caucasian (from England originally, but via Austalia). 
     
    With one of them you simply could not tell, however, the other is clearly mixed.

  2. do you mean she looks all asian or caucasian?

  3. First, I’m not white, my ass is a rich brown, ergo, I’m not “Caucasian.” The nerdy amongst us though might be familiar with the term “Caucasoid,” which shares a relationship with Caucasian 
     
    Razib, I have never used the word ‘Caucasian’ as a synonym for pale skinned or European, and as far as I know, its just a different variation of the word Caucasoid and refers to a physical anthropology cluster: 
     
    “Cau·ca·sian    ( P )  Pronunciation Key  (kô-kzhn, -kzhn) 
    adj.  
     
    1. Anthropology. Of or being a major human racial classification traditionally distinguished by physical characteristics such as very light to brown skin pigmentation and straight to wavy or curly hair, and including peoples indigenous to Europe, northern Africa, western Asia, and India.

  4. Razib, 
     
    She looks caucasian … complete lack of epicanthic fold, higher nose, reduced zygomatic arch, lighter colored skin, and so forth. 
     
    My youngest looks more Chinese, but has a strong mixture of caucasian in there.

  5.  
    She looks caucasian … complete lack of epicanthic fold, higher nose, reduced zygomatic arch, lighter colored skin, and so forth.
     
     
    your wife should get a maternity test :) i had a friend who was half-anglo american half-japanese who was raised in kyoto with her sister. she favored her mother, her sister favored her anglo-american father. ironically, her sister was much more firmly ‘japanese’ in culture, while she was less so. she thought it had to do with overcompensation on her sister’s part (though she too was recognizably ‘gaijin’). phenotype matters, just not in the way way you might think sometimes.

  6. I knew a couple, he was Danish – blond hair, blue eyes, pale skin – and she was African-American – black afro hair, mid-brown color and dark brown eyes. 
     
    They had 2 sons. The first had a dark yellowish skin tone, and light brown eyes, and loose afro dark brown hair. The second on the other hand showed no readily discernible African traits at all – he had olive complexion, dark brown eyes and straight black hair – he could have passed for Italian any day?!

  7. for what it’s worth, russ lande wrote a paper in 1981 which suggested that are 5 primary loci that control human color variation. sampling error is going to result in extinction of “on” alleles in a lot of cases. our own david nierengarten is 1/4 black american, but i saw a pic once and i wouldn’t have guessed.

  8. >5 primary loci 
     
    i’ve heard of newer work that confirms that number, but yet other work that’s found additional loci that modify skin color

  9. can you post the cite?

  10. I had freind growing up in india dad was indian mom was american of nordic descent from minnesota. my friend was blond and blue eyed as were all his 4 siblings. to the point that we used to call him gori gaand ( white ass).

  11. >can you post the cite? 
     
    I don’t think it’s been published yet.

  12. vic, the india part though is confusing because there is a lot of variance within india. i knew of a man who was from allahbad whose family were minor muslim nobility of ashraf (west asian) descent. his skin was pale olive, and his 3 children with his white american wife were auburn-haired. on the other hand, this chick is half pakistani but she looks full brown to me.

  13. are they of large additive effect? epistatic? etc.? do you know?

  14. if i remember correctly, this was a whole genome association study in a south asian population for skin color (and height?) 
     
    i’ve been waiting to see it published in nature or science for a while now 
     
    the other loci — I wasn’t paying much attention during that talk and so nearly missed it being mentioned in passing 
     
    it might be a while before that work gets published

  15. “this chick is half pakistani but she looks full brown to me” 
     
    She resembles, quite strongly, a woman with whom I worked several years ago – who was completely white.

  16. I would expect that since the autosomal genes are recombinant, people aren’t as mixed as they(some at least) would probably prefer to believe themselves to be. 
    Autosomal recombinant alleles will be introduced into a family, are passed on for some time and are often ultimately lost unless pop. frequencies are very high for that allele at that locus, right? In other words, it ceases to matter to anyone whether such and such a dutchman had a great-great grandfather who was an eighth brown or whatever. It does not make him a “mutt”, or a mixedman. A man from whom we are twenty five generations removed is not a parent anymore, and certainly not if he wasn’t a genetic relative of the population at large.

  17. A man from whom we are twenty five generations removed is not a parent anymore, and certainly not if he wasn’t a genetic relative of the population at large. 
     
    you push back far enough there starts to be a large deviance between geneological intuition and genetic reality. and ‘far back’ might be great-grandparents.

  18. “In other words, it ceases to matter to anyone whether such and such a dutchman had a great-great grandfather who was an eighth brown or whatever. It does not make him a “mutt”, or a mixedman.” 
     
    It *would* matter in the United States, however, thanks to the infamous one-drop rule.

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