Human Biodiversity (4): The Importance of Culture in Gene-Culture Coevolution

The readers of Nicholas Wade's Troublesome Inheritance should notice the importance of culture in his argument.  While he rejects the "culture alone" or "all-culture" position, he embraces a "mostly culture" view of institutions in his account of gene-culture coevolution (6, 57-61, 241). 

Consider the following comments.  "Culture is far more important in most short-term interactions.  As with most human behaviors, the genes provide just a nudge in a certain direction" (53).  "A society's achievements, whether in economics or the arts or military preparedness, rests in the first place on its institutions, which are largely cultural in essence.  Genes may nudge social behavior in one direction rather than another, thus affecting the nature of a society's institutions on the timescale of the generations and setting the framework within which culture operates, but this is a long-term effect that leaves ample room for culture to play a major role" (250).  "The genes that govern human behavior seldom issue imperatives.  They operate by setting mere inclinations, of which even the strongest can be overridden.  There are almost certainly genes that predispose people to regard incest as abhorrent, yet cases of incest are far from rare because those neural prohibitions can be ignored.  Because the prompting of behavior genes can be resisted, ingrained social behavior may be subject to a variety of manipulations, ranging from education and social pressure to tax incentives.  In short, many social behaviors are modifiable and this is probably the case even if they are genetically influenced.  Where behavior is concerned, genetic does not mean immutable" (250-51).

One might even see here a gene-culture-judgment coevolution.  Genes constrain but do not determine culture, and genes and culture jointly constrain but do not determine judgment.  Within the constraints of genetic nature and cultural traditions, individuals are free in their judgments in ways that can alter the course of human history.

There are many examples of the power of culture in Wade's argument.  He notes that "the universal instinct to conform to social rules seems to ensure that the political behaviors of the host country supplant those of the immigrants.  Chinese Americans do not organize themselves into authoritarian structures, nor Arab and African Americans into tribal ones" (188).

Even in Africa, the African tribalism that has impeded economic development has recently shown some signs of change.  Over the past 15 years, sub-Saharan Africa has had some of the fastest rates of economic growth in the world.  Wade acknowledges this, and he observes: "fierce pressures are clearly at work in the continent, and people will adapt to them.  These adaptations may include a reduction of tribalism" (176-77).  (A good survey of the remarkable improvements in Africa over recent decades was written by Oliver August as a long special report for The Economist, March 2, 2013.)

The cultural environment can also have a powerful effect on IQ scores.  Wade observes:

"IQ scores increase 10 or more points in a generation when a population becomes richer, showing clearly that wealth can raise IQ scores significantly.  East German children averaged 90 in 1967 but 99 in 1984.  In West Germany, which has essentially the same population, averages range from 99 to 107.  This 17 point range in the German population, from 90 to 107, was evidently caused by the alleviation of poverty, not genetics.

"There is a 10 to 15 point difference in IQ scores between the richer and poorer countries of Europe, yet these differences disappear when the inhabitants migrate to the United States, so the differences are evidently an environmental effect, not a genetic one.  If European IQ scores can vary so widely across different decades and locations, it is hard to be sure that any other ethnic differences are innate rather than environmental" (192).

This shows the "Flynn effect"--IQ scores rising as the result of environmental changes, particularly modern education that stimulates improving cognitive abilities.

As another example of how cultural conditions can change genetic nature, Wade indicates that while the races have arisen when people were fragmented into small tribal groups with little intermarriage, the modern move away from ethnocentric tribalism to inclusive societies is bringing increasing intermarriage that is reversing the racial differentiation of the human species (71, 78-80).  This ultimate triumph of inclusive institutions through racial intermarriage could eliminate racial tribalism.

What one sees here is that far from being racist, Wade's scientific argument for overcoming ethnocentric tribalism is actually a powerful argument against racism as belonging to a primitive stage of human evolution.