Question: Could difference in average intelligence also be (theoretically) linked without common descent due to common selection factors? (I believe you may have earlier indicated that you accepted that it could, but I’m trying to clarify - sorry)
Sure, however I see no reason to believe that selection for intelligence truly varies by environment in a way which would produe something like racial differences. Above all because it seems fairly clear to me that brain function is controlled by many, many alleles and that interaction is going to be complex. Thus, as you can imagine, it would be rather extraordinary (and require heavy selection pressure imho) to produce large-scale regional variations.
I hope I’m approaching clarity now on this issue.
I have not made one single personal attack against you. I have said your are wrong. I have asked you to clarify yourself after too much doublespeak. I have presented cites and links to back up my claims.
You continue to insist that there is some kind of “PC agenda” when told that there is no scientific basis for race. You are right if by “PC agenda” you mean “conclusions reached through rigorous research and the scientific method.”
Now I suggest you stop the personal attacks and address the issue at hand.
correlating visual traits like ‘black’ skin and tight curly hair, or asian eye shape and straight black hair.
i guess a better phrase is ‘visible traits’. i don’t know where i got ‘visual’ from.
*Originally posted by zwaldd *
I guess I misunderstood your question. Your talking about about intellectual capacity or intellectual capabilities?
Right. But what causes such fury amongst people is that their is a single “something” called intelligence and that this “something” called intelligence can be passed on to future generations, and that this “something” called intelligence can be inferred meanigfully from a person’s outward physical appearance.
And no one’s saying that it can’t. People’s intellectual capacities (capabilties?) DO differ. But you can’t then group then into categories based on outward, physical appearances. You can’t say that Whites have a lower intellectual capacity than blacks, and then say it’s based on some genetic component based on their skin color. A person’s skin color, hair texture, body build, etc. doesn’t have anything to do with their intellectual capabilties.
You CAN say that whites differ in their intellectual capabilties than blacks, but the differences would be based on cultural, social, economic, etc. factors.
Exactly.
Well, the whole reason “The Bell Curve” and other research has caused such controversy is that their conclusions imply there ARE limits to intellectual capabilties.
Here’s the gist of their arguments: Whites are smarter than blacks because they score higher on IQ tests. Therefore, blacks intellectual capabilties are lower than whites. And why is that? Because of blacks genetic makeup.
The counter argument - peoples intellectual capacities are basically the same. And why is that? Because, genetically, people are basically the same. That is, the variation in people’s intellectual capacities will be the same across all known “racial” categories. Differences in mental capabilties, if and when they do occur, can be attributed to non-bilogical/non-genetic factors.
Well, I probably didn’t provide what your looking for, and I apologize. I’m not an expert in this area. I’ll leave you to look through the copious citations provided by Collounsbury and others. I’ll also suggest you read “The Mismeasure of Man” by Stephen Jay Gould. I just bought the book myself and will read it whenever I find time.
hmmm. they might mean the same thing to me. i think what you’re capable of intellectually at any given time in your life is based on your brain’s physical capacity for intelligence as well as how you’ve learned to think up until then. in any case, all an iq test measures is how well you reason through the questions at the time you take the test.
no you can’t, but you can hypothesize that skin color or a combination of any regularly correlating visible traits does or does not correlate with intellectual capacity and then set out to prove it. first you have to figure out how to physically measure intellectual capacity. i don’t think iq tests measure that.
i don’t know if i agree with that. again, i don’t think we currently have a means of measuring intellectual capability.
*Originally posted by zwaldd *
I agree.
Right, and then show that that correlates meaningfully with any visible traits. But, correlation doesn’t equate to causation. There very well could be other factors involved.
I don’t either - just pointing out that it’s the one most used.
Well, maybe I didn’t word it quite the way I intended. You could hypothesize that whites differ in their intellectual capabilties than blacks, but only insofar as it relates to cultural, economic, social, etc. factors. Various IQ tests do measure intellectual capabilties to some degree (modified to account for cultural/social differences). From those findings using IQ tests, it appears that their isn’t any meaningful difference (if you use IQ test scores as a proxy for mental capabilities).
However, I would have to agree with you - I don’t think we currently have any meaningful way to measure intellectual capabilties.
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Yes. Good. Another gold star for Daniel. 
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Um, right. I think? Yes, if you agree with me and C-bury that there’s no genetic basis for “race”, and if you understand that you can’t go around any more saying, “Negroids are taller and faster than other races,” then you are not a racist. Right. You are officially absolved from the sin of Racism, go in peace, my son.
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Yes, right again. And it’s another gold star! You’re really racking 'em up here!
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Um, which “statement” would that be? 
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Um, no, this is not true. All of the definitions I came up with fit you and your statements perfectly.
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Um, that’s because there ISN’T a “genetics definition of race”. They can’t use something that doesn’t exist except in the minds of racists.
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Hmm. I find myself in the exceedingly awkward position of addressing an otherwise normally functioning adult who doesn’t seem to know where Uncle Sam GETS those definitions. Ah. I will pretend you are my son Bonzo and are only 13 years old.
“Mom, how does the government know how many blacks there are in the United States?”
“Why, my dear, our federal government conducts what we call a ‘census’ every 10 years. They send you a form, and on the form it asks you what race you are, and you fill in the blank.”
“But, why do they need to know how many Americans are black and how many are white?”
“Because culturally speaking, Americans have a long history of needing to know whether someone is ‘black’ or ‘white’, and government reflects the people who compose it. So we have federal programs called Affirmative Action, and other things like pork barrel funding for inner city anti-drug programs, and it makes a difference politically whether it’s for poor black kids or poor white kids.”
Okay?
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You already posted this back on Page 1. I replied on page 2,
Daniel, here is something new to think about. Do you remember back in sixth grade Health class, there was an illustration in the Health textbook of a man with all his skin removed, so you could see all his muscles? This link is the closest I could get to it, after a short Google search. (No, it’s not gross. 
)
http://pc65.frontier.osrhe.edu/hs/science/muscles1.gif
Okay, here’s the situation. You’re the coroner for the borough of Queens, New York. You’re what’s known as a forensic pathologist. You spend your days down in the morgue, doing autopsies on dead bodies that the cops bring in. Picture the room with the stainless steel table and the drains in the floor, the big refrigerated drawers that slide out to reveal dead bodies with toe tags attached to them.
One day the cops bring you what looks like the handiwork of a particularly nasty gonzo killer, some kind of ultimate Silence of the Lambs wannabe. The body is that of a full-grown human being, but all the skin has been carefully removed. Every last little smidgen, even the fingers and toes have been skinned, so no fingerprints, of course. Even the ears and nose have been removed. No scalp, no hair, no skin on the soles of his feet, no male dangly bits between his legs. This John Doe looks just like that sixth grade Health textbook illustration.
You peer up between John Doe’s legs and see that he hasn’t got a vagina, so he must be a male. But-- what are you going to put in the blank on the official form, where it says, “Race”?
If you’re right, Daniel, and there’s some way to tell from genes what race John Doe is, then all you have to do is send a tissue sample to the lab and they’ll look at his DNA and be able to tell you.
But, you know what? There ain’t no such DNA test. That’s the whole point of this thread. Oh, sure, the lab could look to see whether he’s got a gene for sickle cell anemia, or Tay-Sachs disease, but caucasians get sickle cell anemia and Tay-Sachs disease, too, so the presence of either of those genes wouldn’t tell you anything.
Nope, you’re just going to have to leave the space for “Race” blank on the form. There’s no way to tell.
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Yes, you did. You said,
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No, you didn’t. What you said was,
You did NOT say, “Other people have shown that there is statistical evidence”. You said, “I think there is statistical evidence”. There is a considerable difference between the two statements.
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And that’s exactly what it is–speculation. No more, no less.
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Yes, you did. You said,
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Yes, I agree with you. There are differences between “races”, but they are only skin-deep, only outward physical characteristics.
Okay, you really don’t see that these two statements are contradictory?
One statement is, “One cannot say that blacks are taller than whites.”
The other statement is, “Blacks are taller than whites.”
And the statement, “Blacks are taller than whites” is not true. One cannot “say it with certainty”. If you have some kind of statistic that proves it, please, by all means, trot it out and post your cite.
Betcha can’t. 
And it is racist to say, “Blacks are taller than whites.” Making categorical statements about whole groups of people based on their “race” is what we call “racism”, and people who make those kinds of statements are what we call “racists”.
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Um, I don’t recall saying that being taller is better. Are you perhaps speaking to someone else? Or else show me where I said that, there’s a good boy…
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Control-C Copy. Control-V Paste.
Making categorical statements about whole groups of people based on their “race” is what we call “racism”, and people who make those kinds of statements are what we call “racists”.
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Are you really not getting this, Daniel? Or are you just being deliberately obtuse?
No, silly, saying “Blacks have dark skin” isn’t racist, because you’re just pointing out a fact. “Blacks have dark skin. Chinese have slant eyes. Caucasians have fair skin.”
But when you progress from merely noting a fact to assuming that certain behaviors or physical or mental characteristics will also be present in people, just because they’re black or Chinese, that’s racism. “Blacks are taller and faster than other races. Chinese are smarter than other races.” That’s racism.
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Right. And we already discussed where they get these definitions from. The People of the United States of America provide them themselves, every 10 years, during the census. And we already discussed why the government has those definitions.
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Ah ha!! Yes, but the Oxford Dictionary DOES NOT GO ON TO SAY, “Negroids are taller and faster than other races”. Saying, “Negroids are taller and faster than other races” is a racist sentiment. The editors at the Oxford Dictionary DO NOT express this sentiment, THEREFORE they are not racist. You are being silly again, like with the rancher.
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You’re absolutely right. I understand a certain Dr. Mengele got some very interesting test results on hypothermia, back in the 1940s.
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You’re right. The authors presumably funded it themselves, with the hope of eventually making a killing from having a book on the New York Times best seller list.
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Okay, that’s a good point. However, as I already pointed out, that’s not really the reason why The Bell Curve has been discredited. The main reason The Bell Curve has been discredited academically, scientifically, not merely in the popular press, is, first, because no reputable scientists have ever come forward with research that substantiates what’s in the book, and second, because since it was published, many reputable scientists HAVE come forward with research that totally discredits it scientifically.
It has really very little to do with where the research came from.
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I doubt whether all the research that has been done discrediting The Bell Curve has been posted on the Web. So, yes, those were just “book reviews”. However, they talked about the serious research that did discredit The Bell Curve. They told us, “This book has now been discredited,” and they told us why. So it isn’t necessary for us, the readers, to go find the research papers ourselves, even if we could. Are you saying that the credibility of book reviews is suspect, just because they aren’t scientific research papers? Are you saying the writers of those book reviews would lie, and say, “The Bell Curve is now discredited,” and then just make up some cites for spurious research papers? Why would they do that?
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Um, it wasn’t meant to be “solid scientific” criticism. It was a book review, written by a book reviewer.
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Um, yeah, it took a while for people to go out and do research, and then write it up and get it published. Real science, as opposed to junk science or voodoo science, takes time.
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Sorry, I totally fail to discern your point here, or your patent sense of triumph, of a point scored somehow. In other words, “Huh?”
So, um, now that you know about it, is it maybe helping you to rethink your viewpoint?
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You’re right, you did, and I was glad to see that you understood that interesting little thing about the “science” of statistics. You said on page 1,
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But then you went on to say:
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–and all my hopes were dashed.
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Here’s the dictionary definition of “ad hominem”.
The book reviews didn’t appeal to feelings or prejudices rather than intellect. They didn’t attack the authors’ characters, rather than focusing on the allegations made in their book. The book reviews didn’t say, “These men are racists, and therefore their book is racist.” The book reviews said, “This book is racist, and therefore the men who wrote it are racists.” That’s not the same thing as an ad hominem attack.
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But you’re right, the book reviews, however we characterize them, didn’t serve to totally discredit it, but they did serve to post valuable warning signs to readers everywhere, that maybe this particular New York Times bestseller ought to be taken with a grain of salt.
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You’re beating the war drums unnecessarily here, Daniel. Nobody in this thread thinks that a mere ad hominem attack on a study will discredit it. If that were true, then Kent Hovind would long ago have discredited Stephen Jay Gould.
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[falling to knees]
Yes!! Thank you, God…
ok, i think we’re understanding each other on this.
that’s the point i was trying to make. one visible trait doesn’t cause the other, but if you know that a person has asian eye shape, you can reasonably predict that the person will have straight black hair (are we in agreement on that? maybe i’m assuming too much). what i still want to know is how that’s possible if it’s not due to a genetic thread and whether it’s been proven that there aren’t other physical correlations that are not so obvious.
i understand what you’re saying here, but i disagree. you can hypothesize that the intellectual capabilities of whites and blacks have or don’t have a physical component, but until you can prove it, it’s just a hypothesis. not having the means to prove something doesn’t automatically rule it out.
*Originally posted by zwaldd *
Well, I don’t know. I’ll concede this - there probably is a strong correlation between someone having straight black hair and their having an asian eye shape. But tell me this - If I say I have black straight hair, can you tell me what kind of eye shape I have?
Having asian eye type may strongly correlate with having black straight hair, but having black straight hair doesn’t necessarily mean one would have asian type eyes. The relationship isn’t symmetrical. That is, you may find a correlation in one direction (asian eye type with black straight hair), but not in another direction (black straight hair with asian eye type).
Do that with other outward physical characteristics, and you can see that your correlations begin to break down.
Well, I don’t know. I seriously doubt it, but I could be wrong.
What degree of evidence/proof is required that would satisfy you? If one marshall’s a huge amount of evidence that states that the differences in mental capabilties do not correlate with outward physical characteristics, but correlate better with other factors (such as economic status, education levels, culture, etc.) regardless of outward physical appearances, what are you going to conclude?
You can still cling to the possibility that there might be some as yet “internal” physical characteristic (say, brain structure) that correlates with some outward physical characteristic (say, hair color), and that these two also correlate with differences in mental capabilities. But at what cost? You’d have to show there’s a genetic link (brain structure -> hair color - > mental capabilties) and that it is symmetrical (mental capabilties -> hair color - > brain structure). An you have to rule out other genetic effects, along with environmental/cultural/social/economic factors as well. Seems like a lot of effort to try and prove something that would produce trivial results at best and specious results at worst.
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My original statement was “it is not impossible that a study can show that one race has, on the average, slightly higher intelligence than another”. You called that racist. You were wrong.
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I ASKED THE QUESTION, “Is is not true that negroid races are taller & faster than the oriental races?” I did not make this a statement. It was a query, a question, one asking for a reply. It was a loaded question, yes, where I was figuring a bunch of folk would say “YES”, and then I could say- well, if you can say they are “faster”, then why can’t somebody else say they are “smarter”? Becuase it IS a commonly held BELIEF that blacks are faster (true, blacks have won more Gold medals that orientals- but there certainly could be cultural reasons for this disparity).
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NO-, it is NOT RACIST to say the “On the average, blacks are taller than orientals”. UNLESS- you an evryone else is convinced that “being taller” is “better” or more superiour. Racism is NOT where one says “race X is (darker, taller, shorter, has more curly hair, etc) than another race. Eacism is when one says ONE RACE IS BETTER THAN ANOTHER- NOT JUST DIFFERENT. Oxford- “Racism”:” A belief in the superiority of a particular race; predjudice based on this". Find me a freaken Dictionary that says that racism is the belief that races DIFFER from one another, esp in minor physical outward traits- such as skin color & height. Find it or retract & apologize.
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Coroners cannot tell, with assurance, what race a person is from DNA or genetic testing. These tests are new, anyway. They can tell from skeletal structure- at least sometimes.
i don’t see why you think symmetry is important here. the fact remains that asians have straight black hair almost exclusively. africans have tight curly hair. what is the connection between being asian, having slanty eyes (sorry if that’s not the politically correct term - i don’t know what is), and having straight black hair? black skin and curly hair? it’s been argued in this thread that race is arbitrary and that there’s no genetic connection between correlating physical characteristics over a population. so what’s the connection? why isn’t there a significant population of curly haired asians, or straight haired africans?
*Originally posted by zwaldd *
Zwaldd, see below…after posting this, make up your own conclusions. Again, I’m not an expert in this area. I’ve probably confused things rather than shed any light on the matter. If so, I apologize. Maybe we can go over this again sometime in the future over in GD. Let’s leave this Pit thread to Danielinthewolvesden and Duck Duck Goose.
From The History and Geography of Human Genes by L. Cavalli-Sforza, et. al (1994), pp. 19-20.
1.6 Scientific Failure of the Concept of Human Races
The classification into races has proved to be a futile exercise for reasons that were already clear to Darwin. Human races are still extremely unstable entities in the hands of modern taxonomists, who define from 3 to 60 or more races (Garn, 1971). To some extent, this latitude depends on the personal preference of taxonomists, who may chose to be “lumpers” or “spliters.” Although there is no doubt that there is only one human species, there are clearly no objective reasons for stopping at any particular level of taxonomic splitting. In fact, the analysis we carry out in chapter 2 for purposes of evolutionary study shows that the level at which we stop our classification is completely arbitrary. Explanations are statistical, geographic, and historical. Statistically, genetic variation within clusters is large within compared with that between clusters (Lewontin, 1972; Nei and Roychoudhury, 1974). All populations or population clusters overlap when single genes are considered, and in almost all populations, all alleles are present but in different frequencies. No single gene is therefore sufficient for classifying human populations into systematic categories.
As one goes down the scale of the taxonomic hierarchy toward the lower and lower partitions, the boundaries between clusters become even less clear. The evolutionary explanation is simple. There is great genetic variation in all populations, even in small ones. This individual variation has accumulated over very long periods, because most polymorphisms observed in humans antedate the seperation into continents, and perhaps even the origin of the species, less than half a million years ago. The same polymorphisms are found in most populations, but at different frequencies in each, because the geographic differentiation of humans is recent, having taken perhaps one-third or less of the time the species has been in existence. There has therefore been too little time for the accumulation of a substantial divergence. The difference between groups is therefore small when compared with that of major groups, or within a single population. In addition, out species and its immediate predecessor, Homo erectus, showed considerable migratory activity in all directions, some of which are likely to have resulted in admixtures between branches that had seperated a long time before. Whatever genetic boundaries may have developed, given the strong mobility of human individuals and populations, there were probably never were any sharp ones, or if there were, they were blurred by later movements. There may still exist weak genetic boundaires in some regions, but they only mean that there has been less local admixture across certain barriers (See, for instance Barbujani and Sokal, 1990; Sokal, et al., 1988).
From a scientific point of view, the concept of race has failed to obtain any consensus; none is likely, given the gradual variation in existence. It may be objected that the racial sterotypes have a consistency that allows even the layman to classify individuals. However, the major sterotypes, all based on skin color, har color and form, and facial traits, reflect superficial differences that are not confirmed by deeper analysis with more reliable genetic traits and whose origin dates from recent evolution mostly under the effect of climate and perhaps sexual selection. By means of painstaking multivariate analysis, we can identify “clusters” of populations and order then into a hierarchy that we believe represents the history of fissions in the expansion to the whole world of anatomically modern humans. At no level can clusters be identified with races, since every level of clustering would determine a different partition and there is no biological reason to prefer a particular one. The successive levels of clustering follow each other in a regular sequence, and there is no discontinuity that might tempt us to consider a certain level of reasonable, though arbitrary, threshold for race distinction. Minor changes in the genes or methods used shift some populations from one cluster to the other. Only “core” populations, selected bacause the presumably underwent less admixture, confer greater compactness to the clusters and stability to the clasification tree. Although the hope of producing a good taxonomy is a lost cause - a minor scientific loss - that of reconstructing evolutionary history retains full strength and has the advantage that hypotheses can be tested on the basis of other, independent sources of data. Greater confidence in the conclusions must come from agreement with external sources of relevant evidence rather than from internal analysis.
The word “race” is coupled in many parts of the world and strata of society with considerable prejudice misunderstanding, and social problems. Xenophobia, political convenience, and a variety of motives totally unconnected with science are the basis of racism, the belief that some races are biological superior to the others and that they have therefore an inherent right to dominate. Racism has existed from time immemorial but only in the nineteenth century were there attempts to justify it on the basis of scientific arguments. Among these, social Darwinism, mostly the brainchild of Herbert Spencer (1820-1903), was an unsuccessful attempt to justify unchecked social competition, class stratification, and even Anglo-Saxon imperialism. Not surprisingly, racism is coupled with caste prejudice and has been invoked as motivation for condoning slavery, or even genocide. There is no scientific basis to the belief of genetically determined “superiority” of one population over another. None of the genes that we consider has any accepted connection with behavioral traits, the genetic determination of which is extremely difficult to study and prsently based on soft evidence. The claims of a genetic basis for a general superiority of one population over another are not supported by any of our findings. Superiority is a political and socioeconomic concept, tied to events of recent political, military, and economic history and to cultural traditions of countries or groups. This superiority is rapidly transient, as history shows, whereas the average genotype does not change rapidly. But racial prejudice has an old tradition of its own and is not easy to eradicate.
Buzzt, wrong. (1) Asian eye shape I assume means some kind of epithantic fold. Sorry (a) occurs outside of asia, including some populations in Africa (b) occurs in populations in Central Asia and South East Asia who no not have ‘straight black hair’, and to respond in part to your follow up message, there are indeed significant populations of Asians without straight hair a la Japanese etc (not withstanding the modern demographic dominance of Han chinese and their relatively recent diaspora). Your classificatory issues notwithstanding. As for Africans, well, this all depends on who you want to call African, but if you think that all more or less black Africans have the same hair type, you’re wrong. Again, dealt with in detail in prior threads, with citations.
So, yes, you are assuming too much.
Zwald, you have not done the reading my dear fellow. IF you follow through with the citations provided in the other threads, much of this sort of matieral will be addressed.
Already noted previously that physical characteristics have converged and diverged in populations otherwise ‘closely related’ e.g. South East Asian ‘Negrito’ populations with the range of ‘negroid’ characteristics from 100% Africanesque physical morphology to something in between ‘negriod’ morphology and more stereotypically ‘Asian’. Genetic analysis has clearly ruled out a recent direct African input, rather surface morphology shifted under selection pressures.
Your assumption that somehow surface morphologies must reflect underlying genetic commonalities has already been dealt with. It is not a case of it can’t be, but rather that it isn’t the case. That evidence is clear.
The problem here is the categories. Neither the category White nor Black reflect a coherent biological entity, the genetic evidence on this is ABUNDANTLY CLEAR. Without compelling evidence to suggest underlying commonalities, and in fact with the preponderance of solid evidence suggesting the opposite, the proper scientific conclusion is to discard racial based hypothesizing as fundamentally flawed and move on to coherent, biologically defined units.
So, once more, rather than having me simply regurgitate the same basic issues over and over, why not read the prior threads. This board is supposed to be about eradicating ignorance, and I have always assumed old threads are saved for just that purpose. I would refer you especially to the Eugenics thread for the most concise set of information, including cites.
epon- that was a very good post, with an excellent cite. (Altho I do rather think you went more than a ‘tad’ over our allowance of quoting 'short" passages). If some other folks had put it that way, i would be educated, rather than pissed off.
Note that this viewpoint is rather new, and did not take hold until the middle 90’s. I was taught entirely different stuff about "race, in a science course, as little as 25 years ago. However, times do change, and i am happy to learn new info. However, folks- remember that quote about catching flies with honey instead of vinegar?
I’m with you Daniel. Honey is the answer.
Too much vinegar in the world.
I don’t see that you should have to “defend” yourself further. Let this thread go. You can’t win an argument if no one is listening to you.
There will be other threads to argue on, but this one ran off the rails long ago.
Just to spread the wealth, I went back and copied my little store of standard citations and the like, esp. for Zwald. I shall try to provide further sickle cell data, although I don’t really believe it necessary to address your point.
Note, some of this is duplicative of epon and other’s cites, but duplication seems necessary for this topic, plus I’m too lazy to edit this. (Note, this is from page two of the Eugenics thread)
Try checking out, for a general discussion: Goodman, Allan. “The Problematics of “Race” in Contemporary Biological Anthropology.” in Biological Anthropology: The State of the Science 1995. Among some things other things to read are Cavalli-Sforza, L Luca; Menozzi, Paolo; & Piazza, Alberto. “Scientific Failure of the Concept of Human Races,” in _The History and Geography of Human Genes. Princeton University Press (Princeton, 1994): 19-20.
In regards to the later, the authors explain how genetic information abundantly proves that there are no distinct “races” in the human species. The number of “races” identified by recent authors who cling to the “race” concept ranges from 3 to 60. “Race” classifications are arrived at without consistent criteria. C-S et al note that there is without question only one human species. All attempts to find smaller groupings within the human species are entirely arbitrary. Gene frequencies vary so greatly within particular populations that they prove useless for distinguishing among geographically defined populations. Even the most isolated human groups carried with their founders diverse sets of genes; large regions of the world are all well known to have experienced many migrations and consequent exchanges of genes.
C-S et al conclude “From a scientific point of view, the concept of race has failed to gain any consensus; none is likely, given the gradual variation in existence. It may be objected that the racial stereotypes have a consistency that allows even the layman to classify individuals. However, the major stereotypes, all based on skin color, hair color and form, and facial traits, reflect superficial differences that are not confirmed by deeper analysis. . . .” What I and Tom have said all along, in other words…
There are two levels of variability to consider. Intra and inter-group (within and between group) variations in the genome. C-S’ considers an analysis of that part of our genome which can be measured by various markers (of allele
variation) of the 6% to 15% of our variability –not our entire genome note, of our *variability, which is a vanishingly small 1% or so-- which varies by region or group. The difference in the estimates depends on the markers used. Templeton, using the “classical” blood markers gets around 15%, others get around 6% using more refined methods.
I.E. our variation by things which one might call racial is tiny! Say, at maximum 15% of approximately 1%. (Some refs:
re much lower degree of mtDNA variability among modern humans see M. Ruvolo et al. [1993] Molecular Biology and Evolution 10: 1115-1135; re much less Heterozygosity of modern humans than in other primates see D. N. Janczewski et al., [1990] Journal of Heredity 81: 375-387
re Human races not having unique set of shared derived characters characterizing any human ‘race’ see P. A. Morin et al. [1994] Science 265: 1193-1201;
re max mtDNA maximum for humans (1.1%) for other primates, around 3% see R. L. Cann et al. [1987] Nature 325: 31-36. Also Research by Maryellen Ruvolo, Proceedings of the National Academy of Sciences 13/9/66. which examined mtDNA estimated mutation rate of 0.8% per million years. It estimated gorillas separated from chimps and humans cica 8-10 MYA; humans and chimps circa 6 MYA. Found a very large difference between mtDNA of Gorilla gorilla gorilla (W Africa lowland) and E. Africa species G. g. graueri and G. g. beringei indicating a split about 3 MYA and almost making them separate species. Most interesting was how little variation there was in human mtDNA. “Her findings support previous research showing that modern humans are remarkably less diverse genetically than are the great apes. 'The most different humans on the face of the earth are less different than two lowland gorillas from the same forest in West Africa.”)
As Templeton says in connection with his paper, “Human Races: A Genetic and Evolutionary Perspective,” (American Anthropologist, Fall 1998) “The 15 percent is well below the threshold that is used to recognize race in other species. In many other large mammalian species, we see rates of differentiation two or three times that of humans before the lineages are even recognized as races. Humans are one of the most genetically homogenous species we know of. There’s lots of genetic variation in humanity, but it’s basically at the individual level. The between-population variation is very, very minor.”
Added bonus: Mark Seielstad, Endashaw Bekele, Muntaser Ibrahim, Amadou Touré, and Mamadou Traoré "A View of Modern Human Origins from Y Chromosome Microsatellite Variation " Vol. 9, Issue 6, 558-567, June 1999
Online at:
http://www.genome.org/cgi/content/abstract/9/6/558
Summarizes many of the issues in population genetics in its introduction, although it really deals with paleoanthropological issues, but contains some nicely stated critiques of how to approach markers and their meaning.
Similar issues are discussed in:
Francis S. Collins,1 Lisa D. Brooks,1,3 and Aravinda Chakravarti2 “A DNA Polymorphism Discovery Resource for Research on Human Genetic Variation”
Online at:
http://www.genome.org/cgi/content/full/8/12/1229
And perhaps most on subject is
Kenneth M. Weiss “PERSPECTIVE: In Search of Human Variation” Vol. 8, Issue 7, 691-697, July 1998
Online at:
http://www.genome.org/cgi/content/abstract/8/7/691
And also from a paleo perspective but reaffirming our conclusions:
Robert Foley “PERSPECTIVE: The Context of Human Genetic Evolution” Vol. 8, Issue 4, 339-347, April 1998
Online at:
http://www.genome.org/cgi/content/full/8/4/339
(mostly the intro, although the paleo stuff is fun and interesting.)
And while I’m at it, why not read this paper?
Mark Stoneking, Jennifer J. Fontius, Stephanie L. Clifford, Himla Soodyall, Santosh S. Arcot, Nilmani Saha, Trefor Jenkins Mohammad A. Tahir, Prescott L. Deininger, and Mark A. Batzer: “LETTERS: Alu Insertion Polymorphisms and Human Evolution: Evidence for a Larger Population Size in Africa”
Vol. 7, Issue 11, 1061-1071, November 1997
Online at:
http://www.genome.org/cgi/content/full/7/11/1061
Since it shows how population issues are addressed in context, not 100% relevant but what the heck I thought it was an interesting article and since I’m in a sharing mood.
Also Li Jin, Peter A. Underhill, Vishal Doctor, Ronald W. Davis, Peidong Shen, L. Luca Cavalli-Sforza, and Peter J. Oefner
“Distribution of haplotypes from a chromosome 21 region distinguishes multiple prehistoric human migrations” Vol. 96, Issue 7, 3796-3800, March 30, 1999
is kinda fun.
I decided to rummage around re sickle cell rates in Med, Central Asia and India. Fraid this is a little more challenging to search on than expected, probably due to my unfamiliarity with the specific terminology in order to track down data on population frequencies. In any event, for the interim, I offer the following which while not providing hard data, does characterize frequency in passing. Somewhat weak, but I do have other work to do:
A Ashley-Koch, Q Yang and RS Olney
“Sickle hemoglobin (HbS) allele and sickle cell disease: a HuGE review” American Journal of Epidemiology, Vol 151, Issue 9 839-845
“Sickle cell disease is caused by a variant of the beta-globin gene called sickle hemoglobin (Hb S). Inherited autosomal recessively, either two copies of Hb S or one copy of Hb S plus another beta-globin variant (such as Hb C) are required for disease expression. Hb S carriers are protected from malaria infection, and this protection probably led to the high frequency of Hb S in individuals of African and Mediterranean ancestry.” (emphasis added)
I hope that this will help set aside Zvald’s unsupported assumption that non-African occurance of sickle-cell traits is ‘trivial’. I would attribute the lack of reference on-line to the understandable focus on the English speaking world’s major sickle-cell carriers (African diaspora).
Hope this helps.
I stumbled across this reference, which I do not have access to, but apparently has further demographic information (albeit somewhat old):
Livingstone, F. B. (1967) Abnormal Hemoglobins in Human Populations: A Summary and Interpretation (Aldine Publishing Company, Chicago).
Cited in
Margaret J. Mackinnon, D. M. Gunawardena, Jagath Rajakaruna, Sudath Weerasingha, Kamini N. Mendis, and Richard Carter “Quantifying genetic and nongenetic contributions to malarial infection in a Sri Lankan population” Proc. Natl. Acad. Sci. USA, Vol. 97, Issue 23, 12661-12666, November 7, 2000
in the context of their analysis of genetic contribution to malarial resistance in Sri Lanka:
“The pattern suggests that the genetic control of P. falciparum infection does not confer absolute susceptibility or refractoriness to infection but rather modulates the probability of infection and the density of parasites during infection. Such effects would be consistent with the known presence in South Asian populations of inherited blood disorders that give partial protection against clinical illness from P. falciparum such as sickle cell trait (hemoglobin S), hemoglobin E, the thalassemias, and glucose 6-phosphate dehydrogenase deficiency (40).” where citation (40) is to the text cited above.
Also, I was interested to read the following analysis from
Stephen M. Rich*, Monica C. Licht, Richard R. Hudson, and Francisco J. Ayala “Evolution: Malaria’s Eve: Evidence of a recent population bottleneck throughout the world populations of Plasmodium falciparum” PNAS Vol. 95, Issue 8, 4425-4430, April 14, 1998
“We have analyzed DNA sequences from world-wide geographic strains of Plasmodium falciparum and found a complete absence of synonymous DNA polymorphism at 10 gene loci. We hypothesize that all extant world populations of the parasite have recently derived (within several thousand years) from a single ancestral strain. The upper limit of the 95% confidence interval for the time when this most recent common ancestor lived is between 24,500 and 57,500 years ago (depending on different estimates of the nucleotide substitution rate); the actual time is likely to be much more recent. … A demographic sweep that started several thousand years ago is consistent with worldwide climatic changes ensuing the last glaciation, increased anthropophilia of the mosquito vectors, and the spread of agriculture. P. falciparum may have rapidly spread from its African tropical origins to the tropical and subtropical regions of the world only within the last 6,000 years.”