Human Biodiversity (6): Would the Recent Genetic Evolution of Human Beings Subvert Darwinian Natural Right?

The most provocative claim of Nicholas Wade's Troublesome Inheritance is that "human nature changes over time" (151).  Of course, anyone who accepts the Darwinian theory of human evolution must believe that human nature changes over long periods of evolutionary time, because the human species arose from ancestral species over a long period of hundreds of thousands or millions of years.  This suggests that the biological human nature that we know today is not eternally unchanging, but it is relatively stable, in that the rate of genetic change is very slow.  But what happens if we are persuaded by Wade that human genetic evolution has been occurring over periods of thousands or even hundreds of years; so that, for example, Greg Clark might be right that the English Industrial Revolution required the genetic evolution of "bourgeois virtues" in the English over a 400-500 year period?

I am wondering if this subverts my argument for "Darwinian natural right," which assumes the stable reality of evolved human nature, including the 20 natural human desires, as setting the natural standard for judging moral and political traditions.

In Darwinian Natural Right: The Biological  Ethics of Human Nature,  I respond to the objection that the Darwinian evolution of the human species promotes a radical relativism because it denies the eternal or everlasting permanence of the species (232-38).  If the human species, like any evolved species, is not eternal or everlasting but a contingent result of evolutionary history that can change and even pass away, does that indicate that the human good as relative to the natural desires of the evolved human species is contingent and unstable?  If the human species is in flux, does this lead us to relativism or nihilism?

That the good of a species exists only as long as the species exists should not disturb us, I argued, unless we believe that the objective reality of the human good depends on its being an eternal good.  Even if species are not eternally fixed or everlastingly permanent but have evolved from ancestral species and are headed for extinction in the future, that does not make them any less real for as long as they endure.  Even if we cannot appeal to the permanent things, we can appeal to the enduring things.

But how enduring is the human species?  In my book, I quote a remark by Stephen Jay Gould: "Species are stable entities with very brief periods of fuzziness at their origin."  But this is exactly what Wade denies, because he argues that human genetic changes--including genetic changes that influence personality and behavioral traits--have actually accelerated over the last 10,000 years.  And therefore people like Gould--as well as the evolutionary psychologists like Tooby and Cosmides--are wrong in their assumption that human genetic evolution mostly stopped 10,000 years ago.  The "fuzziness" of the human species has continued right up to the present.

Wade does indicate, however, that the rate of genetic change is always much slower than the rate of cultural change.  "A primary effect of genetics is to add a substantial degree of inertia or stability to the social behavior and hence to the institutions of each society.  Rapid change must be due to culture, not genetics, but if the core social behaviors of each civilization have an evolutionary foundation, . . . then the rate of change in their relationships is likely to be constrained" (246).

One should also notice that the recent genetic changes claimed by Wade are not changes that have transformed the human species into a new species, but changes that create differentiation within the human species.  Like Gregory Cochran and Henry Harpending (in The 10,000 Year Explosion: How Civilization Accelerated Human Evolution), Wade compares the genetic differentiation of different human populations to the similar differentiation of dog breeds through artificial selection.  All dogs belong to the same species, but the different breeds are quite different.  Border collies are a whole lot smarter than beagles.  And your chances of being attacked by a pit bull terrier are about a 1,000 times greater than your chances of being attacked by a border collie.

As I have indicated in previous posts, Wade has not proven his case.  He admits that he cannot demonstrate the truth of his claims, because he cannot point to the exact genetic changes underlying changes in human social behavior that he postulates to exist, and so he is forced to engage in a lot of speculation unsupported by empirical proof.

Furthermore, I don't see that the recent genetic evolution that he sketches in his speculative history causes any great problem for Darwinian natural right, because I don't see that he shows that there has been any change in the 20 natural desires, which constitute the evolved human psychological ground for natural right.

If the good is the desirable, and if evolved human nature shows a stable profile of 20 natural desires that have not radically changed over the past 10,000 years, then we have an enduring standard for judging some societies as more desirable than others. 

In fact, we see Wade engaged in just this kind of judgment throughout his book. He repeatedly argues that some social orders are better than others--"inclusive" social orders are better than "extractive" social orders--because the better societies are better at satisfying the full range of natural human desires.

I have written some other posts on the biological and moral reality of species here and here.