Debunking Denialism

Defending science against the forces of irrationality.

Mailbag: The Absurdity of Race Realism

I am always happy to answer reader emails set to me via the contact form at the About page of this blog. This email comes from “Nigel”. Nigel writes that:

Speaking about denialism, what about politically correct race-deniers? These people are so wrapped up on some ideology of Boasian Cultural Marxism that they regularly try to subvert the truth.

In just this short message, consisting of nothing more than two sentences, Nigel has managed to set off my baloney detector several times. This is because phrases such as “politically correct” and “cultural Marxism” are buzzwords frequently used by extremist right-wing…thinkers, who are often anti-immigration. “Politically correct” designates their belief that they are being suppressed by the establishment and “cultural Marxism” signifies the related idea that the establishment was been taken over by leftists who ignore the truth that race realists think is plain as day. Thus, Nigel has carried out two very common denialist tactics that I described in the article Common Denialist Tactics Defined and Destroyed, namely playing the martyr card and conspiratorial thinking:

Tactic: Playing the Martyr Card.
Description: Instead of replying with solid evidence or arguments, denialists often complain that they are being persecuted by the establishment because, in their own view, they are questioning the dogmatic status quo. Comparisons with Galileo or Einstein are extremely common.
Countermeasure: Explain that criticism is not the same as persecution, that science thrive on overturning old ideas and replacing them with ideas that better fit the evidence.

Tactic: Conspiratorial Thinking.
Description: In order to explain away embarrassing facts or problems, a conspiracy theory is proposed, which not only lacks evidence but is absurd on many levels.
Countermeasure: Explain that it is a bad idea to attribute things to malice that could equally well be explained by human ignorance or stupidity, that something would have leaked by now or that results would have been too unpredictable and the cost of failure too large for the risk of carrying it out to be worth it.

The question of race depends on, as do so many other questions, on definitions. When we use the term “race”, what are we talking about? In a previous entry, I discussed some of the problems with race realism. Specifically, I noted the problem that traditional racial categories are not biologically sound, but rather form groups. Pigliucci and Kaplan (2003) explains that:

Biological research on race has often been seen as motivated by or lending credence to underlying racist attitudes; in part for this reason, recently philosophers and biologists have gone through great pains to essentially deny the existence of biological human races. We argue that human races, in the biological sense of local populations adapted to particular environments, do in fact exist; such races are best understood through the common ecological concept of ecotypes. However, human ecotypic races do not in general correspond with ‘folk’ racial categories, largely because many similar ecotypes have multiple independent origins. Consequently, while human natural races exist, they have little or nothing in common with ‘folk’ races.

In other words, Pigliucci and Kaplan, rejects traditional racial categories because they are biologically invalid, but draw the trivially true conclusion that local populations of humans can be adapted to their particular environment. This, however, does not justify racial realism, which is much stronger position. They continue:

And of course, as has already been noted, insofar as folk races are supposed to pick out populations that systematically differ from each other over a wide range of genetic and phenotypic measures, biology provides no support for the existence of such populations (and indeed, provides evidence that no such populations exist).

Another instructive bit of evidence against traditional racial categories is the distribution of human genetic variation. Rosenberg et. al. (2002) studied almost 400 short tandem repeats from over 1000 individuals from around 50 populations. He showed that “within-population differences among individuals account for 93 to 95% of genetic variation; differences among major groups constitute only 3 to 5%”. Again, different local populations of humans may be adapted to the environments which in they live, but this shows that the vast majority of human genetic variation lies within populations, not between them.

Nick Matzke (2012) explains that human genetic variation is characterized by mostly continuous geographic structure, rather than discrete races. In doing so, he quotes Templeton (1998):

The genetic data are consistently and strongly informative about human races. Humans show only modest levels of differentiation among populations when compared to other large-bodied mammals, and this level of differentiation is well below the usual threshold used to identify subspecies (races) in nonhuman species. Hence, human races do not exist under the traditional concept of a subspecies as being a geographically circumscribed population showing sharp genetic differentiation. A more modem definition of race is that of a distinct evolutionary lineage within a species. The genetic evidence strongly rejects the existence of distinct evolutionary lineages within humans. The widespread representation of human “races” as branches on an intraspecific population tree is genetically indefensible and biologically misleading, even when the ancestral node is presented as being at 100,000 years ago.

Attempts to salvage the idea of human “races” as evolutionary lineages by invoking greater racial purity in the past followed by admixture events are unsuccessful and falsified by multilocus comparisons of geographical concordance and by haplotype analyses. Instead, all of the genetic evidence shows that there never was a split or separation of the “races’” or between Africans and Eurasians. Recent human evolution has been characterized by both population range expansions (with perhaps some local replacements but no global replacement within the last 100,000 years) and recurrent genetic interchange. The 100,000 years ago “divergence time” between Eurasians and Africans that is commonly found in the recent literature is really only an “effective divergence time” in sensu Nei and Roychoudhury (1974, 1982). Since no split occurred between Africans and Eurasians, it is meaningless to assign a date to an “event” that never happened. Instead, the effective divergence time measures the amount of restricted gene flow among the populations (Slatkin 1991).

Because of the extensive evidence for genetic interchange through population movements and recurrent gene flow going back at least hundreds of thousands of years ago, there is only one evolutionary lineage of humanity and there are no subspecies or races under either the traditional or phylogenetic definitions. Human evolution and population structure have been and are characterized by many locally differentiated populations coexisting at any given time, but with sufficient genetic contact to make all of humanity a single lineage sharing a common, long-term evolutionary fate.

I think I will end here, but there are a lot more to say about how race realists abuse principle component analysis and statistics in general in order to prop up their ideological crusade.

So in conclusion, the existence of “race” depends on what we are talking about. Can local populations be adapted to their environment? Yes. Do genetic variation that have medical implications exist in these populations? Yes. Are traditional racial categories based on scientific evidence? No.

I’m sorry Niles, you are on the side of the denialists this time.

References and further reading

Kaplan, J. and M. Pigliucci. (2004). On the concept of biological race and its applicability to humans. Philosophy of Science 70: 1161-1172

Matzke, N. (2012). Continuous geographic structure is real, “discrete races” aren’t. The Panda’s Thumb. Retrieved: 2012-03-04.

Templeton, A. R. (1998). Human Races: A Genetic and Evolutionary Perspective. American Anthropologist 100(3), 632-650.

Rosenberg, N. A. et al. (2002). Genetic structure of human populations. Science 298, 2381–2385.

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15 responses to “Mailbag: The Absurdity of Race Realism

  1. Thaumas Themelios March 12, 2012 at 17:03

    Excellent break down, as usual, Emil.

    • m steinberg June 29, 2012 at 05:45

      Sadly it’s rather one sided. I would recommend Steve Hsu or Razib Khan’s posts on the topic.

    • Emil Karlsson June 29, 2012 at 18:50

      Unfortunately, you are performing the well-known denialist tactic of “false balance”.

      Common Denialist Tactics Defined and Destroyed:

      Tactic: False Balance.
      Description: Tries to exploit fairness by pretending that there are two different positions, yet equally valid of attention. Teach the controversy, hear both sides and equal time are common manifestations of this tactic.
      Countermeasure: Explain that just because two positions are expressed with the same level of confidence does not mean that the truth lies in between. Sometimes one side is just wrong, especially if it is not supported by the evidence. Point out that it would be unfair to listeners if it was pretended that ignorant and dangerous pseudoscience was presented as fact.

  2. m steinberg June 29, 2012 at 05:33

    ***So in conclusion, the existence of “race” depends on what we are talking about. Can local populations be adapted to their environment? Yes. Do genetic variation that have medical implications exist in these populations? Yes. Are traditional racial categories based on scientific evidence? No.***

    The traditional categories reflect historical geographic separation of groups (evolutionary history). Hence the clusters that consistently show up (Lahn & Ebenstein, “Let’s Celebrate Human Genetic Diversity” Nature 2009). As with races in other species, individuals can be allocated to these groups with a high degree of confidence with by genetic analysis or simple inspection (morphological features).

    Unless you want to make an argument that humans are unique from other species in not having this within species variation, I’m not sure what the fuss is about. You can actually see the major races or population groups here.

    “The tree divides the populations into five broad groups: African, East Asian, West Eurasian (European, Middle Eastern, and Central and South Asian populations), American, and Oceanic. Although the latter branch contains the MEL, PAP, and AuR groups, AuR show a shorter branch length than the others, placing them closer to the trunk of the tree than the other Oceanic populations. This could be the result of greater genetic drift in the MEL and PAP or admixture of the AuR with populations elsewhere on the tree.”

  3. Emil Karlsson June 29, 2012 at 19:05

    No, traditional racial categories to not reflect historical geographic separation of groups. This is because they consists of multiple ecotypes that have a proximate independent evolutionary origin. For instance, all individuals characterized as “black” are not more closely related to each other than either of them are to people with white skin color. Thus, traditional racial categories are not monophyletic, and therefore biologically invalid.

    Humans do have between-group variation, but the fixation index for human populations is very small, on the order of 0.1. To conclude that subspecies exists, a fixation index of at least 0.25 is required.

    The claims in the Nature reference you posted is based on a straw man fallacy of Steve Rose. He corrected the errors of Lahn & Ebenstein in Rose, S. (2009). Research into group differences isn’t wrong, just pointless. [10.1038/462035c]. Nature, 462(7269), 35-35.

    The original commentary by Rose is Rose, S. (2009). Darwin 200: Should scientists study race and IQ? NO: Science and society do not benefit. [10.1038/457786a]. Nature, 457(7231), 786-788, which explains that:

    The categories judged relevant to the study of group differences are clearly unstable, dependent on social, cultural and political context. No one, to my knowledge, is arguing for research on group differences in intelligence between north and south Welsh (although there are well-established average genetic differences between people living in the two regions). This calls into question the motivation behind looking for such specific group differences in intelligence, sheds doubt on whether such research is well-founded, and begs whether answers could possibly be put to good use. As we shall see, a more thorough look at the field will prove that it fails all three of my criteria for justifiable science.

    as well as

    race’, the problem is whether it is a biologically, as opposed to socially, meaningful category. Among geneticists interested in differences in gene frequencies between populations, there is increasing consensus that the word obscures more than it reveals, and should be replaced by the concept of biogeographic ancestry, which makes possible the study of subpopulations for relevant genetic and phenotypic characteristics. There are some well-recognized, meaningful genetic differences between groups, for instance between Ashkenazi and Sephardi Jews in terms of their risk to Tay–Sachs disease, and the study of such differences may reveal important clues with respect, for instance, to disease propensity. But such groups are not normally considered socially distinct races for the purposes of studies of group differences in intelligence. Broad divisions between ‘white’ or ‘Caucasian’ and ‘black’ or ‘Asian’, the groups generally discussed in the context of the IQ debate, especially in the United States, hide genetically important subpopulation differences within these groups

    Finally,

    The standard approach of population biologists to estimating the potential genetic contribution to a trait is to make a heritability estimate. Whatever the strengths and weaknesses of this measure within a population, it is essentially just that: a within-population measure, only valid for a given environment. The nature of the equations means that if the environment changes, the heritability estimate changes too. Moreover, the measure relates to a randomly interbreeding population — useful for agricultural purposes such as estimating optimal genotypes for crop yields or milk production — but not for people. Even if reliable correlations were found between some intelligence test score and a measure of brain physiology or activity held by a specific group, such a correlation says nothing about the direction of causation.

    To make the situation worse for race realists, the article you are referring to is abusing principle component analysis (PCA) by taking a couple of individuals with vast geographical distances apart. This creates the illusion of genetic clustering because the genetic variation in the geographical areas between them are being ignored. If you put that data into the PCA, you would see nothing but roughly continuous geographical structure.

    I suggest you carefully study the references in this blog post, such as Matzke’s article called Continuous geographic structure is real, “discrete races” aren’t.

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  6. Rich July 22, 2013 at 10:17

    “…the vast majority of human genetic variation lies within populations, not between them.”

    That’s not true. What you’re describing is an old myth that was debunked years ago by A.W.F. Edwards (“Human genetic diversity: Lewontin’s fallacy,” BioEssays 2003). You’re also misrepresenting Rosenberg’s findings. In the quote you pulled, he’s repeating Lewontin’s fallacy, but in the very next sentence he says this:

    Nevertheless, without using prior information about the origins of individuals, we identified six main genetic clusters, five of which correspond to major geographic regions, and subclusters that often correspond to individual populations.

    If you look at K=5 in Fig. 1 of the study, you can see that those five genetic clusters correspond clearly to Negroids, Caucasians, Mongoloids, Austro-Melanesians and Native Americans, the five main “discrete races”.

    “Humans do have between-group variation, but the fixation index for human populations is very small, on the order of 0.1. To conclude that subspecies exists, a fixation index of at least 0.25 is required.”

    That’s not true either. Humans have higher between-group variation than many other animals that scientists do divide into subspecies.

    When measures of genetic distance are used such as Wright’s FST, which describes the fraction of the variation attributable to population subdivision, values indicative of great levels of genetic differentiation have been obtained for humans (0.156) based on the analysis of autosomal loci [39] (great levels of genetic differentiation correspond to values of between 0.15 and 0.25 [40]). This contrasts with scores indicative of little to moderate levels of genetic differentiation in other animals (again obtained by looking at autosomal loci), such as the Canadian lynx (0.033) [28], which is recognized as having three subspecies, and the African buffalo (0.059) [24], which is recognized as having five subspecies.

    (M.A. Woodley, “Is Homo sapiens polytypic? Human taxonomic diversity and its implications,” Medical Hypotheses 2010)

    • Emil Karlsson July 22, 2013 at 11:46

      Lewontin’s fallacy?

      That’s not true. What you’re describing is an old myth that was debunked years ago by A.W.F. Edwards (“Human genetic diversity: Lewontin’s fallacy,” BioEssays 2003).

      I am always highly amused when race realists spout the “you are performing the Lewontin fallacy!!1″ when modern post-Lewontin data showing that there is more genetic diversity within groups than between are presented. Yes, Lewontin used a problematic method, but his general conclusion, using more solid methods, have been vindicated.

      The conclusion that there is more genetic diversity within groups than between does not rest on Lewontin. The conclusion (“within-population differences among individuals account for 93 to 95% of genetic variation; differences among major groups constitute only 3 to 5%”) was based on the raw data analyzed by Rosenberg and colleagues. Lewontin and his method is completely irrelevant for that fact.

      Rosenberg data

      You’re also misrepresenting Rosenberg’s findings. In the quote you pulled, he’s repeating Lewontin’s fallacy, [...]

      Again, Rosenberg and colleagues are not using Lewontin’s data or methods at all. Bringing up Lewontin is kind of like creationists bring up Haeckel in an attempt to undermine modern developmental biology. It is just a bait-and-switch tactic.

      Genetic clusters?

      [...] but in the very next sentence he says this:

      Nevertheless, without using prior information about the origins of individuals, we identified six main genetic clusters, five of which correspond to major geographic regions, and subclusters that often correspond to individual populations.

      If you look at K=5 in Fig. 1 of the study, you can see that those five genetic clusters correspond clearly to Negroids, Caucasians, Mongoloids, Austro-Melanesians and Native Americans, the five main “discrete races”.

      Those genetic clusters that you see on that PCA graph do not represent discrete races. Rather, those genetic clusters are statistical artifacts due to low sampling density.

      David Serre and Svante Pääbo (2004) explains this in detail:

      Genetic variation in humans is sometimes described as being discontinuous among continents or among groups of individuals, and by some this has been interpreted as genetic support for “races.” A recent study in which >350 microsatellites were studied in a global sample of humans showed that they could be grouped according to their continental origin, and this was widely interpreted as evidence for a discrete distribution of human genetic diversity. Here, we investigate how study design can influence such conclusions. Our results show that when individuals are sampled homogeneously from around the globe, the pattern seen is one of gradients of allele frequencies that extend over the entire world, rather than discrete clusters. Therefore, there is no reason to assume that major genetic discontinuities exist between different continents or “races.”

      They also point out that:

      Clines, Not “Races”

      Using a homogeneous sampling strategy and a model in which allele frequencies in the different inferred populations are allowed to be independent, we find a stable and reproducible representation of human genetic diversity in which the extent of admixture between individuals in Eurasia and the Americas changes continuously with geographical distance without any major discontinuities (Figs. 2 and 3). Between Eurasia and Africa, the Mediterranean Sea does not seem to act as a major barrier because people from Algeria are similar to people from western Europe except for an ∼10% admixture from inferred population C. Between Eurasia and the Americas, the lack of individuals from North America in the CEPH diversity panel limits the ability to draw conclusions. However, it is interesting that Mayan individuals from Mexico are more similar to East Asian individuals than are individuals in South America. In the light of these results, and in agreement with extensive studies of classical genetic markers (Cavalli-Sforza et al. 1994), it seems that gradual variation and isolation by distance rather than major genetic discontinuities is typical of global human genetic diversity.

      In other words, while differences between human populations exists, the data shows a mostly continuous genetic variation and not discrete races. “Discrete races” was just an artifact of non-homogeneous sampling:

      The current results are also not unexpected in view of the fact that identical DNA sequences of several kilobases are found on different continents (Kaessmann et al. 1999; Gabriel et al. 2002). In fact, as much as a third of the entire human diversity of common haplotypes may be contained within single individuals (Pääbo 2003). However, in spite of this, there is a great tendency in the literature to use a few populations from the extremes of continental landmasses (such as in Fig. 1A) to make worldwide inferences about substructures in the human gene pool. In fact, because human genetic diversity tends to be distributed clinally, it is especially problematic to sample the extremes of continents because this will create the impression of sharp discontinuities in the distribution of genetic variants.

      They also reproduce the finding that most genetic diversity exists within groups than between:

      In fact, also in the current data set, 87.6% percent of the total diversity is found among individuals and only 9.2% among continents (Excoffier and Hamilton 2003), in agreement with many previous studies (e.g. Lewontin 1972; Owens and King 1999; but see also Edwards 2003)

      They go on to discuss the attempted justification of discrete “races” due to medical issues:

      The absence of strong continental clustering in the human gene pool is of practical importance. It has recently been claimed that “the greatest genetic structure that exists in the human population occurs at the racial level” (Risch et al. 2002). Our results show that this is not the case, and we see no reason to assume that “races” represent any units of relevance for understanding human genetic history. In clinical practice, the “classification” of people into “races,” as recently suggested (Risch et al. 2002; Burchard et al. 2003), could perhaps have some justification as a proxy for differences in environmental and other factors of relevance for public health or to help identify rare disease alleles (Phimister 2003). However, in the absence of other knowledge, most alleles influencing susceptibility to disease or outcome of medical interventions cannot be expected to show significantly different frequencies between “races.” An exception may be genes where different selection regimes have acted in different geographical regions. However, even in those cases, the genetic discontinuities seen are generally not “racial” or continental in nature but depend on historical and cultural factors that are more local in nature.

      I doubt that you will read it, but for those that want to know more about human diversity, I strongly recommend it. This is a paper that just keeps on giving.

      That’s not true either. Humans have higher between-group variation than many other animals that scientists do divide into subspecies.

      You attempt to justify this using a reference to a paper published in the journal Medical Hypotheses. However, it is generally considered to be a crank journal, having published a lot of pseudoscience including anti-GMO, claims about vaccines and autism, HIV/AIDS denialism. It did not even apply peer-review at the time the paper you reference was published.

      At any rate, the notion of “subspecies” for humans are defeated by the fact that human genetic diversity lacks strong continental clustering and is better described by a cline. I have the creeping suspicion that the subspecies in the species you list are more like ecotypes than races.

      This further undercuts your case for race realism, which is already shot to pieces with the shotgun of rational science.

    • Rich July 23, 2013 at 10:40

      It’s evident that you haven’t read Edwards’ paper, and that you don’t really understand the subject, because Lewontin’s “general conclusion” has in no way been vindicated. Quite the opposite actually, and Rosenberg’s study is one of the works cited by Edwards as an example of research that disproves the fallacy. Since then, there have been many others.

      Rosenberg published a rebuttal to Serre and Pääbo destroying their “genetic-clusters-are-statistical-artifacts-due-to-low-sampling-density” argument.

      With all other variables held constant, geographic dispersion is seen to have comparatively little effect on the degree of clustering. Examination of the relationship between genetic and geographic distance supports a view in which the clusters arise not as an artifact of the sampling scheme, but from small discontinuous jumps in genetic distance for most population pairs on opposite sides of geographic barriers, in comparison with genetic distance for pairs on the same side. Thus, analysis of the 993-locus dataset corroborates our earlier results: if enough markers are used with a sufficiently large worldwide sample, individuals can be partitioned into genetic clusters that match major geographic subdivisions of the globe, with some individuals from intermediate geographic locations having mixed membership in the clusters that correspond to neighboring regions.

      (“Clines, clusters, and the effect of study design on the inference of human population structure,” PLoS Genetics 2005)

      The data I quoted from the Medical Hypotheses study are sourced to other studies from Molecular Ecology, Nature, PNAS, and a textbook co-authored by a Harvard biology professor and a Cornell genetics professor, so your ad hominem attack against the journal is a big fail. The unsourced claims you made about Fst and subspecies remain falsified.

    • Emil Karlsson July 23, 2013 at 13:32

      Lewontin’s fallacy — again

      It’s evident that you haven’t read Edwards’ paper, and that you don’t really understand the subject, because Lewontin’s “general conclusion” has in no way been vindicated. Quite the opposite actually, and Rosenberg’s study is one of the works cited by Edwards as an example of research that disproves the fallacy. Since then, there have been many others.

      Again, concluding that most genetic variation lie within groups than between groups using modern data is not an example of Lewontin’s fallacy. Lewontin’s fallacy was inferring this conclusion based on insufficient number of markers. Thus, what is fallacious is not his conclusion, but his method. No scientist working with modern data rely on Lewontin’s method. So, ironically, you are the one who does not seem to understand what Lewontin’s fallacy is all about.

      I had already exposed your bait-and-switch trick. Why do you continue to deploy it?

      Rosenberg versus Serre and Pääbo

      Rosenberg published a rebuttal to Serre and Pääbo destroying their “genetic-clusters-are-statistical-artifacts-due-to-low-sampling-density” argument.

      You clearly have not understand Rosenberg’s method or response. That is because (1) you have neglected to quote highly relevant information from the paper (thus you are guilty of quoting out of context / selective quoting) and (2) the material you actually quote is inconsistent with the belief in discrete genetic races (another very ironic aspect of your comment) and you have also misunderstood that material.

      The material you did quote

      Here is the segment you decided to quote form the Rosenberg response:

      With all other variables held constant, geographic dispersion is seen to have comparatively little effect on the degree of clustering. Examination of the relationship between genetic and geographic distance supports a view in which the clusters arise not as an artifact of the sampling scheme, but from small discontinuous jumps in genetic distance for most population pairs on opposite sides of geographic barriers, in comparison with genetic distance for pairs on the same side. Thus, analysis of the 993-locus dataset corroborates our earlier results: if enough markers are used with a sufficiently large worldwide sample, individuals can be partitioned into genetic clusters that match major geographic subdivisions of the globe, with some individuals from intermediate geographic locations having mixed membership in the clusters that correspond to neighboring regions.

      Serre and Pääbo had the contention that human genetic variation was more or less continuous and that there were no genetically discrete races because if you sample enough individuals, there is going to be an overlap in the analysis. Sure enough, this is precisely what the quote you posted says: individuals between the geographic locations have mixed membership in the cluster from neighboring regions. This is the very opposite of the notion that genetically discrete racial groups exists. In fact, Rosenberg almost goes as far as to admit this in your quote, deciding to call continuous genetic variation “small discontinuous jumps” due to geographic barriers (essentially the position of Serre and Pääbo). Clustering reflects geographic ancestry, not evidence for the existence of discrete races.

      The material you did not quote

      Perhaps the most embarrassing for your position is the following:

      Previously, it has been observed that when individual genomes are clustered solely by genetic similarity, individuals sort into broad clusters that correspond to large geographic regions. It has also been seen that allele frequencies tend to vary continuously across geographic space. These two perspectives seem to be contradictory, but in this article the authors show that they are indeed compatible.

      Thus, the clustering observed corresponds to large geographic regions and does not contradict the conclusion that allele frequencies vary continuously. Thus, not only does this paper NOT support your position, it actively contradicts your position. For if allele frequencies vary continuously (i.e. genetic variation is continuously), how can genetically discrete races exist? This question is unanswerable from within your interpretational paradigm.

      To clarify this issue, let us look at Witherspoon et al (2007) (which also contain data on Fst values):

      Discussion of genetic differences between major human populations have long been dominated by two facts: (a) Such differences account for only a small fraction of variance in allele frequencies, but nonetheless (b) multilocus statistics assign most individuals to the correct population. This is widely understood to reflect the increased discriminatory power of multilocus statistics.

      The article further points out that clustering is due to geographic ancestry, which is not the same as traditional racial categories.

      In the conclusion section, Witherspoon makes the following forceful point:

      The fact that, given enough genetic data, individuals can be correctly assigned to their populations of origin is compatible with the observation that most human genetic variation is found within populations, not between them. It is also compatible with our finding that, even when the most distinct populations are considered and hundreds of loci are used, individuals are frequently more similar to members of other populations than to members of their own population. Thus, caution should be used when using geographic or genetic ancestry to make inferences about individual phenotypes.

      Medical hypotheses — again

      It does not matter what references the paper uses. The paper is published in a crank journal that did not apply peer-review at the time. Had it been of any scientific merits, the authors would have chosen to send it in to a credible journal. But they did not. Presumably they tried, but got rejected. No serious scientists submit their paper to the worst of the worst journals first.

      Conclusion:

      You have, yet again, consistently misunderstood key aspects of the underlying science. You fail to understand what exactly was the problem with Lewontin’s argument. You abuse the content of multiple scientific papers, quote one of them out of context and clearly do not understand the scientific background. You even attempt to dress up the race realist beliefs in the shroud of science by referencing a paper published in a crank journal. Classic pseudoscience.

    • Rich July 24, 2013 at 11:11

      “Lewontin’s fallacy was inferring this conclusion based on insufficient number of markers.”

      Read Edwards’ paper! You have no clue what you’re talking about. Lewontin’s fallacy was concluding that humans could not be divided into races based on their genes. He was dead wrong, as Rosenberg and many others have shown.

      From Edwards:

      There is nothing wrong with Lewontin’s statistical analysis of variation, only with the belief that it is relevant to classification. It is not true that “racial classification is . . . of virtually no genetic or taxonomic significance”. It is not true, as Nature claimed, that “two random individuals from any one group are almost as different as any two random individuals from the entire world”, and it is not true, as the New Scientist claimed, that “two individuals are different because they are individuals, not because they belong to different races” and that “you can’t predict someone’s race by their genes”. Such statements might only be true if all the characters studied were independent, which they are not.

      “…you are guilty of quoting out of context / selective quoting”

      LOL. I quoted the Abstract, which summarizes the methods, findings and conclusions of the study. You’re guilty of grasping at straws.

      “For if allele frequencies vary continuously (i.e. genetic variation is continuously), how can genetically discrete races exist?”

      http://www.logicallyfallacious.com/index.php/logical-fallacies/56-argument-of-the-beard

      “…clustering is due to geographic ancestry, which is not the same as traditional racial categories.”

      Actually, they are the same thing, and saying they’re different is a political opinion, not a scientific reality. Even your fellow “race denialists” are forced to concede that fact.

      Nevertheless beyond such a treacherous ideology, we need boundaries, since we need clusters both to achieve group-oriented diagnostics and therapeutics, and to grasp the evolution of Homo sapiens. Of course these clusters must be named in some way. To be honest nothing prevents us from continuing to use the word ‘race’ for them, especially now that we have understood the real epistemological status of this notion and the methodological path used to determine its content. Unfortunately ‘race’ is a too ideologically and historically committed term, and it would be wise not to use it. The history of human culture has showed us that even if words are not dangerous, the humans who use them can be extremely dangerous.

      (L. Lorusso and G. Boniolo, “Clustering humans: on biological boundaries,” Stud Hist Philos Biol Biomed Sci 2008)

      I suggest that typical uses of the concept of geographic race today are simply crude labels imposed upon this geographically structured variation. In that sense, race is culturally constructed, as all labels are, but it is also based on an underlying reality of biological variation. … The final question is one of semantics. In cases where broad geographic groups are used, should we refer to these groups as “races” or should we use more politically correct terms such as “geographic regions” or “geographic clusters?” On the one hand, the very concept of “race” has such historical baggage that continued use of the term tends to reify incorrect conceptions of human variation. On the other hand, it is probably naive to think that the term can be wiped from everyday use and misuse.

      (J.H. Relethford, “Race and global patterns of phenotypic variation,” Am J Phys Anthropol 2009)

      “It does not matter what references the paper uses.”

      It “does not matter” to you because they’re totally legit and they prove you wrong. Unfortunately for you, I can also do that without the Medical Hypotheses paper.

      The range 0 to 0.05 may be considered as indicating little genetic differentiation.
      The range 0.05 to 0.15 indicates moderate genetic differentiation.
      The range 0.15 to 0.25 indicates great genetic differentiation.
      Values of FST above 0.25 indicate very great genetic differentiation.

      (D. Hartl and A.G. Clark, “Principles of population genetics,” Sunderland, MA: Sinauer Associates 1998)

      The German population sample showed zero Fst with the CEU sample whereas the Finns from Kuusamo and the southern Italians were most different from them (Fst = 0.013 and 0.008, respectively) (Table S2). Pair-wise Fst values for CEU and either Latvians, Lithuanians, Estonians or western Russians were intermediate (0.006, 0.005, 0.004 and 0.004, respectively).

      Two or more samples were available from several countries which allowed us to measure the intra-population variability by Fst. Mean Fst was 0.001 for the 14 Estonian counties, 0.005 for Finland, 0.000 for Germany and 0.005 Italy (each with two samples), and 0.007 for the HapMap CHB and JPT samples. Multi-sample populations were taken from the final PC map to demonstrate the substructure of the populations (Figure S3).

      Pair-wise Fst of the four HapMap samples (203 individuals in total) were as follows: Europeans (CEU) – Africans (YRI) 0.153; Europeans (CEU) – Japanese (JPT) 0.111; Europeans (CEU) – Chinese (CHB) 0.110; Africans (YRI) – Chinese (CHB) 0.190; Africans (YRI) – Japanese (JPT) 0.192; Chinese (CHB) – Japanese (JPT) 0.007.

      (M. Nelis et al., “Genetic Structure of Europeans: A View from the North–East,” PLOS One 2009)

    • Emil Karlsson July 24, 2013 at 13:15

      Lewontin’s fallacy

      Read Edwards’ paper! You have no clue what you’re talking about. Lewontin’s fallacy was concluding that humans could not be divided into races based on their genes. He was dead wrong, as Rosenberg and many others have shown.

      No, Lewontin’s fallacy was concluding that there was more genetic variation within populations than between populations based on single locus analysis. It is ironic that you encourage me to read the paper when you clearly have not done that yourself. Let us see what Edwards actually labels as a fallacy:

      These conclusions are based on the old statistical fallacy of analysing data on the assumption that it contains no information beyond that revealed on a locus-by-locus analysis, and then drawing conclusions solely on the results of such an analysis. The ‘taxonomic significance’ of genetic data in fact often arises from correlations amongst the different loci, for it is these that may contain the information which enables a stable classification to be uncovered.

      In other words, Edwards is labeling Lewontin’s inference as a fallacy.

      Selective quotations

      LOL. I quoted the Abstract, which summarizes the methods, findings and conclusions of the study. You’re guilty of grasping at straws.

      No, you carefully selective segments of the abstracts to quote. In fact, you still do not seem to realize the impact of what you quoted:

      Thus, analysis of the 993-locus dataset corroborates our earlier results: if enough markers are used with a sufficiently large worldwide sample, individuals can be partitioned into genetic clusters that match major geographic subdivisions of the globe, with some individuals from intermediate geographic locations having mixed membership in the clusters that correspond to neighboring regions.

      In other words, these genetic clusters actually overlap based on geography.

      Continuous genetic variation

      “For if allele frequencies vary continuously (i.e. genetic variation is continuously), how can genetically discrete races exist?”

      http://www.logicallyfallacious.com/index.php/logical-fallacies/56-argument-of-the-beard

      My question is not an example of the fallacy of the beard, as genetic clusters do not represents the extremes of a continuum. This is because the earth is spherical. Thus, the individuals used to construct those apparent genetic clusters are right within the continuum, not extremes.

      Genetic clusters are not races

      Actually, they are the same thing, and saying they’re different is a political opinion, not a scientific reality. Even your fellow “race denialists” are forced to concede that fact.

      No, because traditional racial categories are not based on geographical regions. “Black” would encompass people in Africa, North America, the Caribbeans and Papua New Guinea, yet these clearly belong to different geographical regions, and therefore different genetic clusters. This is yet another reason for why the genetic clustering observed is unrelated to traditional racial categories.

      The problem here is that you are starting with your preferred narrative (the alleged scientific validity of traditional racial categories) and then torturing the facts to fit that narrative. It does not work. It will not work.

      Medical Hypotheses

      It “does not matter” to you because they’re totally legit and they prove you wrong.

      Again, Medical Hypotheses is a crank journal that has published everything from HIV/AIDS denialism and anti-GMO fear-mongering. It did not even apply peer-review at the time that paper was published. If that is the best “science” that race realists can prove, then that is quite embarrassing.

      FST values

      he range 0 to 0.05 may be considered as indicating little genetic differentiation.
      The range 0.05 to 0.15 indicates moderate genetic differentiation.
      The range 0.15 to 0.25 indicates great genetic differentiation.
      Values of FST above 0.25 indicate very great genetic differentiation.

      An FST value of 1 indicates speciation. For example, a FST of 0.15 indicates that 85% of genetic variation is within populations and only 15% of genetic variation between populations. It is hardly reasonable to call that “great genetic differentiation”.

      Again, it is not interesting to compare FST for populations living very far away from each other. The geographical distance creates the illusion of discreteness where no such discreteness exists. Remember, the Rosenberg paper you cited states clearly that allele frequencies are continuous.

    • Rich July 25, 2013 at 10:40

      “Let us see what Edwards actually labels as a fallacy:”

      Copying and pasting the first paragraph under the heading “Fallacy” is not reading the paper. You still don’t understand (or don’t want to understand) how Edwards disproves Lewontin’s argument that there’s no genetic evidence for race. Try reading the sections labeled “Conclusion” and “Epilogue.”

      “No, you carefully selective segments of the abstracts to quote.”

      I skipped the introductory first half and quoted the results and conclusions from the second half. You’re still grasping at straws.

      “My question is not an example of the fallacy of the beard, as genetic clusters do not represents the extremes of a continuum. This is because the earth is spherical.”

      The populated parts of the earth are not spherical. Europe is one extreme (beard), and East Asia is another (clean shaven). Some people in the middle have a 5 o’clock shadow. The same applies to the Europe-Africa continuum in the other direction. That’s what Rosenberg means when he says that “some individuals from intermediate geographic locations hav[e] mixed membership in the clusters that correspond to neighboring regions”—i.e., they’re a mix of two different races.

      “‘Black’ would encompass people in Africa, North America, the Caribbeans and Papua New Guinea, yet these clearly belong to different geographical regions, and therefore different genetic clusters.”

      “Black” refers colloquially to the autochthonous people of sub-Saharan Africa, some of whom have migrated to other parts of the world in recent history. There’s a discrete genetic cluster for them. There’s also one for “White,” one for “Yellow,” one for “Brown,” and one for “Red.”

      “Medical Hypotheses is a crank journal that has published everything from HIV/AIDS denialism and anti-GMO fear-mongering.”

      http://en.wikipedia.org/wiki/Association_fallacy

      “The geographical distance creates the illusion of discreteness where no such discreteness exists. Remember, the Rosenberg paper you cited states clearly that allele frequencies are continuous.”

      The Kalash of northern Pakistan are about three times closer to the Chinese geographically than they are to Orcadians, yet genetically they cluster with the Orcadians. That’s one of the “discontinuous jumps in genetic distance” Rosenberg mentions that make the clusters real and robust, and not an artifact of sampling density.

  7. Emil Karlsson July 25, 2013 at 12:11

    Lewontin’s fallacy

    Copying and pasting the first paragraph under the heading “Fallacy” is not reading the paper. You still don’t understand (or don’t want to understand) how Edwards disproves Lewontin’s argument that there’s no genetic evidence for race. Try reading the sections labeled “Conclusion” and “Epilogue.”

    Quoting the relevant sections in an effort to explain to you where exactly the fallacy in Lewontin’s argument lies is highly appropriate. In fact, throughout this discussion, you have (1) brought up criticisms of Lewontin’s work despite the fact that neither I nor my sources appeal to Lewontin’s inference method (in other words you are performing the straw man fallacy) and (2) been chronically unable to accurately grasp exactly were the fallacy in Lewontin’s project lie.

    The fallacy is not stating that there is more genetic diversity within populations than between them. Both Rosenberg and your FST values demonstrate this beyond a shadow of a doubt. The fallacy was, according to Edwards, that Lewontin exclusively used a locus-by-locus analysis and inferred that because his position was true for each locus, it had to be true for multi-locus analyses as well. In other words, the fallacy Lewontin’s inference did was arguably a fallacy of composition. Notice here that it was Lewontin’s fallacy occurred in his inference, not in his conclusion. His general conclusion; that more genetic variation exists within groups than between them, has been corroborated over and over again by modern research. Indeed, not even the staunchest race realist are claiming that humans have FST values of over 0.5.

    Selective quotations

    I am not going to let you get away with your selective quoting. You clearly quoted parts of the paper you felt corroborated your position and left out parts that did not. As I have shown, even the parts you quote do not support your beliefs.

    The facts remain: The Rosenberg reply still showed that (1) genetic clusters overlap and (2) allele frequencies are continuous. From these two conclusions, race realism is refuted. Clustering reflects geographic ancestry, not evidence for the existence of discrete genetic races.

    You also did not address the conclusion of the Witherspoon paper at all. Let me repost it for you:

    The fact that, given enough genetic data, individuals can be correctly assigned to their populations of origin is compatible with the observation that most human genetic variation is found within populations, not between them. It is also compatible with our finding that, even when the most distinct populations are considered and hundreds of loci are used, individuals are frequently more similar to members of other populations than to members of their own population. Thus, caution should be used when using geographic or genetic ancestry to make inferences about individual phenotypes.

    Until you grasp this idea, you position will continue to wallow in ignorance.

    “Black” refers colloquially to the people of sub-Saharan Africa, some of whom have migrated to other parts of the world in recent history. There’s a discrete genetic cluster for them. There’s also one for “White,” one for “Yellow,” one for “Brown,” and one for “Red.”

    Really? You do not see the irony with your racial classification?

    1. Modern science has shown that white Europeans are descendants of black Africans. That would mean, according to the racial categories that you propose, that white Europeans are actually black. Oh snap!

    You can attempt to escape this conclusion by claiming that you only mean black Africans still living in sub-Saharan Africa and descendants that still “look black”, but that would force you to exclude some descendant lineages of black Africans, thus making your allegedly evidence-based racial group of “black” be non-monophyletic. Oh snap again.

    2. You claim is also contradicted by the fact that the group of people who “look black” are not monophyletic. People who “look black” living in Africa, North America, the Caribbeans and Papua New Guinea are not more related to each other than any other ethnic group. This is clear from human migrations derived from mitochondrial DNA. It makes a map like this:

    human migrations

    Thus, people living in e. g. Papua New Guinea, who would be classified as “black” by many race realists (or at the very least who look indistinguishable from people who many race realists would classify as “black”), are actually more closely related to people living in India than Africa and they are not part of the same “discrete genetic cluster”.

    3. You assert that five races exists (you call them “white”, “black”, “brown”, “yellow” and “red”) and claim that these correspond to genetic clusters. However, there are three problems with that: (1) response paper by Rosenberg uses K = 6 at most, (2) there is a lot of admixture in these genetic clusters thus contradicting the claim of discrete racial categories and (3) these clusters do not correspond to your traditional racial categories.

    Let us see why. Look at figure 2 in the Rosenberg response paper. Focus in on the blue genetic cluster. For instance, it contains people living in France, Italy. Thus, this blue genetic cluster would represent what you believe is the “white” race. However, this blue genetic cluster also include many groups living in the Middle East (4) and Central and South Asia (9). Also notice the admixture as you can find blue admixture in many populations and Africa and East Asian.

    Thus, the entire edifice of your assertion that “genetic clusters correspond to traditional racial categories” falls apart.

    You also fail to defend your appeal to a paper published in a crank journal that did not apply peer-review.

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