(Many thanks to Abbas Raza for a couple of reposts at 3 Quarks Daily. 3QD is an excellent filter blog which brings together a daily collection of articles "in the areas of science, design, literature, current affairs, art, and anything else we deem inherently fascinating". In the spirit of this sort of cross-disciplinary eclecticism, in the following post I consider some of the social implications of current debates over evolution.)
A recent lengthy article by Gina Kolata in the Times on anatomical and physical differences between the average American a century ago and today cited the University of Chicago economist Robert W. Fogel to the effect that
Over the past 100 years … humans in the industrialized world have undergone a form of evolution that is unique not only to humankind, but unique among the 7,000 or so generations of humans who have ever inhabited the earth.
Of course, the article hurries to explain, the “evolution” being referred to here involves not “changes in genes, as far as is known, but changes in the human form.” Instead, it is argued that these “changes in the human form,” are actually due to environmental factors such as nutrition, etc. (and particularly, it is argued, conditions during fetal gestation).
Fogel’s non-Darwinian use of the term “evolution” here is actually quite timely, given current debates in Kansas and elsewhere over whether “intelligent design” should be considered a valid alternative to evolution in schools. Even beyond the design vs. evolution “debate,” however, Fogel’s discussion of a “form of evolution” to describe changes due to environmental conditions rather than genetic mutations underscores a series of controversies with the scientific community, as well as within society at large .
These controversies, and their social implications, are perhaps best illustrated by three interrelated debates which appeared on the pages of the NY Times during the first months of last year. First of all, it was in January 2005 that Larry Summer made his now-infamous remarks that the relative dearth of female faculty in the sciences might be due to “issues of intrinsic aptitude.” While the furor unleashed by these remarks contributed quite directly to Summer’s subsequent forced retirement as Harvard president, it is nevertheless widely acknowledged that humans have many sex-based variations in anatomy, physiology, and even cognitive ability (for instance, I believe that it is accepted that girl babies, on average, appear to have a greater initial facility with language than do boy babies), and therefore it is not, prima facie, implausible that adult men and women might, statistically speaking, have differing degrees of “intrinsic aptitude” for different kinds of cognition (including, perhaps, scientific reasoning).
A couple of months later, the New York Times Magazine published a lengthy article on one of Summer’s fellow economists at Harvard: Roland Fryer Jr. (who is both an assistant professor in the economics dept., as well as a junior fellow at Harvard’s Society of Fellows). Fryer, who is black, has explicitly asked why the question of whether “the black-white test-score gap [might] be genetics” shouldn’t in fact “be on the table.” As an example of where this sort of openness to the possibility of genetic difference might lead, the Times piece cites a recent article in which Fryer and his co-authors suggested that disparity of life expectancy between whites and blacks might be due to a higher rate of salt sensitivity among African Americans, which in turn might have been artificially selected during the slave voyages (on the theory that blacks with a higher capacity for salt retention would also retain more water and therefore be more likely to survive the voyage).
The reason why the implications of some of Fryer’s research are controversial is because they question the self-evidence of the well-known dictum (familiar to everyone from critiques of The Bell Curve) that there is almost as much genetic variation within “races” as there is between them, and therefore there is no single attribute which can be mapped directly onto an individual “race.” In an op-ed piece that appeared in the Times (reprinted here) only 4 days before the Fryer profile, however, the biologist Armand Leroi argues strenuously that this dictum (which he attributes to a 1972 article by Harvard geneticist Richard Lewontin) is actually based on a logical error. That is to say, even if the genetic variation within each “race” insures that no single attribute will map directly onto an individual’s “race,” it is, nevertheless, true that correlations of attributes tend to cluster together along acknowledged racial lines. As Leroi puts it, “human physical variation is correlated; and correlations contain information.”
Leroi’s argument (and others like it) have generated a lot of discussion, including, for instance, a thoughtful essay by Alan Goodman published on March 20th (the same day as the Fryer piece), in which he critiques both Leroi’s article as well as a piece by Sean Thomas in the Sunday Telegraph in which he argues that the concept of “race” should be thrown out entirely. Goodman argues that both Thomas and Leroi are wrong—Thomas, because race remains a “lived reality” of significant consequence; and Leroi, because “race” is an unnecessarily “blunt and dull instrument” to adequately address genuine issues of genetic diversity.
I believe that Goodman’s argument is basically correct, and I wonder whether one might use it to critique not only some of Fryer’s attempts (as summarized in the Times piece) to correlate genetics with racial difference, but also, if we were to substitute “sex” for “race,” Summers’ suggestion of a possible link between sex and specific aptitude. (While one make argue that sex, because it is inherently binary, is a much sharper “instrument” than is race, some would argue that this apparent binarism is itself merely a social construct and that sexual difference actually exists across an ill-defined continuum. See, particularly, Judith Butler in Bodies that Matter and elsewhere).
At the same time, Goodman’s common-sensical recognition is that human genetic variation is real (even if existing racial categories are a dangerous imprecise “tool” for specifying these differences, nevertheless brings us back to an one of Leroi’s examples, and to Fogel’s original discussion of “form of evolution.” More specifically, some of the distinguishing characteristics of the Andaman Islands tribes threatened by the 2004 tsunami (with which Leroi opens his article) is that they are “very small, very dark, and have peppercorn hair.”
The characterization of a tribe or race as intrinsically “very small” is quite problematic, and runs directly counter to the central argument of an influential and controversial area of study known as anthropometrics advocated by John Komlos, among others. Like the research summarized in Kolata’s Times article last week, Komlos argues that height is strongly correlated with environmental factors such as nutrition but, contra Leroi and conventional wisdom, he argues that there is no underlying correlation of height with racial difference. That is to say, while Komlos does not dispute that height can be genetically determined, he argues that, when averaged out across entire populations (regardless of ostensible “race”), the range of human height is more or less constant, and is directly influenced by nutrition. Therefore, the average height of a population at any one time (compared with the height of populations from either other regions or other historical period) is a direct indicator of the nutritional quality of that population (or sub-population). Furthermore, Komlos argues that this approach not only applies to the increase in height of average Americans over the past century (as discussed in the Kolata article), but even to “racial” sub-populations traditionally viewed as significantly undersized (he cites examples of their children being adopted into American families and growing to “average” height), but also points to an interesting paradox (not mentioned in the Kolata article) whereby average heights in the US have actually stagnated over the past half century (across all racial, regional, socio-economic, and other obvious distinctions), while they have continued to increase in Western Europe (Komlos infers from this counter-intuitive finding that large gaps in income and wealth are detrimental for society as a whole).
If, therefore, Komlos is basically correct, then what Fogel calls a "form of evolution" actually refers to an increase in nutritional quality and social resources correlating directly to an increase in height, health, and life-expectancy. More abstractly, we might further propose that this "form of evolution" also refers to the ways in which social perceptions of racial or sexual difference may create and exarcerbate those pre-existing (but not necessarily genetically determined) differences themselves. This latter "form of evolution," in other words, refers to the ways in which a discourse of evolution is yoked to a rhetoric of racial or sexual differences in order to further intrench the very real differences which it seeks to describe.
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