From the day it was published in 1859, Darwin’s theory of evolution by natural selection has never ceased to discomfort people. Clerics in the 19th century repudiated his account of human origins. Today Darwin is implicitly rejected by the many social scientists and other academics who deny that there is a biological basis to race.
Most people who hate racism oppose it as a matter of moral principle, before which all other considerations are irrelevant. Not so for social scientists. For many decades they have founded their opposition to racism on a specific scientific condition, namely that race has no biological basis and is solely a social construct.
This formulation is proclaimed on the websites of major social-science organizations. “Race is about culture, not biology,” states the American Anthropological Association. Too bad that it’s incorrect, but that’s not the worst of it. The social-science creed has permeated the thinking of most college campuses so deeply that race, in the genetic sense, has become a taboo word. This has serious consequences for the advance of knowledge.
It’s not that race in itself is of such great interest, although probably the more it is understood the less it will be feared. Rather, recent human evolution cannot be understood except in terms of its independent development on each continent. There is not one story of recent human evolution but several, given that the five major continental populations or races–those of Africans, East Asians, Caucasians, Native Americans and Australasians–have been evolving largely independently since modern humans dispersed from Africa some 50,000 years ago.
It’s hard to explore these stories without acknowledging that race has a biological basis. Yet researchers who do so put their careers in peril if they offend the political leanings of the colleagues who must approve their grant applications or accept their papers for publication.
In a book published last month, A Troublesome Inheritance, I have tried to draw some of the tension from this fraught subject by showing that the understanding of genetic differences between human groups does not lead to racism. The human genome confirms what common sense would suggest, that there is clearly a biological basis to race.
The genome shows that the races are not separated by genes–everyone has the same set–nor even by alleles, the alternative forms of each gene that arise from mutations. Rather, there is a continuum of variation in which the races differ predominantly in the relative frequency of their alleles. It’s hard to see a master race in allele frequencies. The genome emphatically declares the unity of humankind.
The human genome records that natural selection has been regional, meaning that a largely different set of genes has changed under evolutionary pressure in each race. This is just what would be expected given that the populations on each continent have responded to different local challenges. Some of these selected genes are active in the brain, though with unknown function, confirming that the brain is no more exempt from evolution than is the body.
This raises the possibility that human social behavior has been shaped by evolution just as the body has been. Humans being a highly social species, social behavior is critical to a society’s survival and hence likely to be a prime target of natural selection.
Most critics of my book have ignored its major genetic arguments, presumably finding no fault with them, but have lambasted the book for being speculative while invariably neglecting to mention its clear warning to the reader on precisely this point. There’s nothing wrong with speculation; what’s wrong is to pass speculation off as fact. If one cannot speculate about what might be in the genome, how can one know what to look for?
The human genome was first decoded a decade ago. Today there is a serious impasse between a social-science creed that effectively denies evolution has any explanatory role in human affairs and the high goal of exploring what the human genome may say about human origins and evolution.
In the confrontation between religion and evolution in the 19th century, believers eventually perceived that they could not cast Darwin out with a pitchfork and didn’t need to. Faith, as long as it didn’t overreach, could coexist with science, and all but fundamentalists have accepted that arrangement. Social scientists too could safely agree to live with Darwin, once they accept that evolutionary differences between human groups can today be explored without the return of racism.