On August 8, a remarkable letter appeared in the New York Times Sunday Book Review. Written by a group of five leading evolutionary geneticists and signed by another 135, it repudiated the main conclusions of Nicolas Wade’s book A Troublesome Inheritance. Wade was for many years the main science reporter for the New York Times covering developments in genetics and biology. His book purported to summarize the main findings of the research he had been covering: that the European, African, and Asian races are genetically defined and that they have faced different evolutionary pressures that have given them what he claimed are different intellectual, behavioral, and civilizational capacities.
The book has been widely reviewed and, apart from a glowing endorsement from conservative policy writer Charles Murray, has received largely negative assessments. Wade’s main response has been that the commentators lack the stature and expertise to criticize his ideas. Thus, when the 135 scientists, many of whom Wade cites as his own authorities, blasted his argument as “incomplete and inaccurate” and with “no support from the field of population genetics,” his thesis had been dealt a mortal blow.
But to understand what makes the move of these geneticists so remarkable, you need some history and sociology of claims that genetic science explains racial differences in intellect and behavior.
In 1969, educational psychologist Arthur Jensen used ideas from the emerging field of behavior genetics in an article claiming that the IQ and educational achievement gaps between black and white children were due in large part to genetic differences between the races, and that educational efforts to close the gap must therefore fail. This was the era of intense conflicts over civil rights and President Johnson’s Great Society. Jensen’s writings sparked student protests and heated academic debates. Not surprisingly many education scholars, social scientists, and psychologists denounced Jensen’s work, but so too did many geneticists. In 1975, 1,390 members of the Genetics Society of America co-signed a statement that said “there is no convincing evidence as to whether there is or is not an appreciable genetic difference in intelligence between races” and over nine hundred had signed a stronger repudiation of Jensen’s work.
The IQ and race controversy was traumatic for researchers interested in genes and behavior. As debates raged about science, politics, and ethics of the research, the field fragmented into mutually distrusting groups and many geneticists completely abandoned behavior as a topic.
A quarter century later psychologist Richard Herrnstein and Charles Murray published The Bell Curve, an 845 page doorstop that made a very similar argument to Jensen’s: the lack of success of Latinos and African Americans relative to whites and Asians has a strong genetic basis. American inequality, they argued, is mostly genetic. This time, the response was very different. Social scientists and liberal pundits decried the work, criticizing the science and linking it to the history of scientific racism. However, biologists and geneticists largely ignored the debate. Those who tried to intervene, like Stephen J. Gould, were often perceived as politically, rather than scientifically, motivated. Geneticist David Botstein explained his peers’ silence: The Bell Curve “is so stupid that it is not rebuttable.” Members of the Human Genome Project’s (HGP) Ethical, Legal, and Social Issues (ELSI) division hoped to organize project leadership to publicly distance genetics from the book’s racial ideas. It took two years for an ELSI statement to be allowed to appear in a specialist genetics journal, but HGP leadership remained publicly quiet. Soon thereafter ELSI was reorganized and its public activism discouraged.
We tend to think of a scientist’s public responsibility as a matter of individual commitment. But it has much to do with the structure and culture of scientific communities. The IQ controversy from the 1970s had spurred changes driving geneticists’ disengaged approach to The Bell Curve in the 1990s. Conflicts fragmented the research community so geneticists rarely interacted with behavioral scientists and weren’t comfortable engaging their claims critically. Mistrust made it impossible to see public criticism as legitimately scientific rather than purely political. And the outsourcing of ethics to ELSI made it difficult for many geneticists to see the public interpretation of scientific controversies as their business.
The genetic evidence for racial behavioral differences hasn’t changed in the 45 years since Jensen wrote, but geneticists’ public responses have. The recent collective response to Wade’s book is heartening because it indicates that geneticists are coming to see that a new approach to the public interpretation of their science is needed. Because it aims to tell us about human similarities and differences, capacities and potential for change, there will always be a public politics to genetics. The difficult work of the public interpretation of contentious issues cannot be left to social scientists and ethicists (whose genetics credentials will be questioned) or to individual geneticists (whose motivations will be questioned). This group will take heat for their stand, but they cannot be doubted as scientists or marginalized as individuals. They will learn, I believe, that being political in this way—soundly criticizing public misappropriations of their research—can only be good for the long term legitimacy of genetics.
Aaron Panofsky is Associate Professor in Public Policy and the Institute for Society and Genetics at UCLA. His recent book, Misbehaving Science considers the scientific and political controversies surrounding behavior genetics.
SamChevre says
It's worth noting that Kevin Drum's lead-based explanation for crime would also apply to measured intelligence, and his argument (which seems very plausible to me) is that lead exposure was disproportionately high among the poor, who are disproportionately black.
That means that any evidence for Kevin Drum's theory would, in a study not controlling for lead exposure, indicate that the poor-black and white-are on average less intelligent-which is what everyone from Jensen to Murray has argued the data shows. (I am unaware of any study of measured intelligence which showed no difference, on average, between races; most arguments I do know argue the measured intelligence is a skewed metric because it always shows differences.)
JamesWimberley says
For genetics, shouldn't you put "races" in quotes? After all, one of the main issues is whether the observed differences in a wide set of allele frequencies in population groups map in any useful way on to the popular concepts, dominated by the trivial mutation for melanin deficiency. American concepts of "black" and "white" aren't quite as baseless as the Nazis' "Aryan race", but they are still cardboard. For instance, the labelling of the half-Luo Barack Obama as "black" like his African-American (i.e. West African-American) wife Michelle. I offered an argument in this old post (that still gets occasional visitors) that Obama is probably more similar genetically to Hillary Clinton than to Michelle. The argument was not contested, let alone refuted.
RhodesKen says
Genetic modification by botanists involves (these days) grafting and splicing DNA. If you do that to humans, you might produce a race of super-smart humans, or perhaps a race of stupid humans.
But nobody does that. The supposition that there are genetically-based racial differences requires that there be a selection bias to cause certain attributes to be preferentially selected in certain environments. If there are a large number of people in the Sahara region of Africa who have evolved with a greater than normal tolerance for heat and lack of water, that would make perfect sense.
Perhaps there is a geneticist who can explain why stupid would be preferentially selected in some environment. Until that time, though, I will treat all such reports as indicating that the reporter simply doesn't understand how to use statistics, and doesn't understand the post hoc ergo propter hoc fallacy.
JamesWimberley says
"Perhaps there is a geneticist who can explain why stupid would be preferentially selected in some environment."
Unfortunately it's quite easy for an amateur to generate just-so stories along exactly these lines.
1. The Neolithic agricultural revolution dramatically downgraded the mental demands of subsistence from the rigorous ones of hunting and gathering. (Jared Diamond, after spending time in the forests of lowland New Guinea with hunter-gatherers, concluded that they were on average significantly brighter than typical Americans.) Dumb,conservative endurance is the best survival chance for an agricultural labourer. So peasants end up stupid, unlike us aristos and warriors.
2. This applied in spades to slaves. Owners may have tried to breed for low intelligence, but probably with little success. The main genetic impact however lay through the catastrophic death rates in the slave trade and early plantation years, weeding out the intelligent, sensitive and forceful. You'd expect to see some long-term genetic damage in slave-descended populations.
These are merely just-so stories and SFIK there is no actual evidence that these processes had a genetic impact on the respective underclasses. If they did, it would have been stronger on character traits like extroversion, curiosity, initiative, and risk-taking (selected against) and on the other side patience, prudence and stoicism (selected for). It's unclear why intelligence in the sense of the ability to solve problems should be any less useful to the poor and oppressed than the rich and dominant. The solution to the problem is often playing dumb. And of course the same pressure on culture was much stronger and more immediate.
Barry_D says
"Dumb,conservative endurance is the best survival chance for an agricultural labourer. So peasants end up stupid, unlike us aristos and warriors. "
Probably the ability to thrive on a limited diet and to resist disease would be more important.
Barry_D says
"This applied in spades to slaves. Owners may have tried to breed for low intelligence, but probably with little success. "
Is there even a single shred of evidence for this?
"The main genetic impact however lay through the catastrophic death rates in the slave trade and early plantation years, weeding out the intelligent, sensitive and forceful. You'd expect to see some long-term genetic damage in slave-descended populations""
It would kill those more susceptible to disease, and those who died under extremely harsh stress. I don't know why you think that intelligence would not be a useful asset. Sensitivity in certain ways (a keen appreciation of what others feel); forcefulness would be extremely useful, when combined with intelligence (i.e., don't agress against those able to fight back strongly).
JamesWimberley says
Domestic animals are usually less bright than their wild relatives: dogs and wolves. Though dogs have in compensation acquired emotional sensitivity to their masters, and can follow a pointing finger to an object, which wolves apparently do not. But the time-frame of animal domestication is altogether different to human slavery; millennia for most animals, hundreds of thousands of years for dogs. I put possible attempts at selective breeding as as a pure speculation; thin even within the just-so story. Slaveowners certainly had no moral compunctions, but I don' t really see how they could have got it to work. If they wanted slaves to reproduce, and they did, they probably had to accept the slaves' choice of mate.
I understood that depression and suicide - or simply losing the will to live - were very common among new slaves, especially men. It was an environment as extreme as battle, and survival depended on different character traits than those favoured in their societies of origin. We can't rule out some warping of the gene pool, which would have been part of the crime if true. But as I said, I don' t see why intelligence per se would really have been selected against.
SamChevre says
I would also note that something does not need to be "selected for" to be prevalent- it's lack just needs not to be selected against.
Take antibiotic resistance in bacteria; it's rare in most populations, but much more common in populations with a history of exposure to antibiotics. It's not that unexposed populations select against resistance-they just don't select for it.
All the accounts of "why" are just-so stories, as James Wimberley notes.
NCGatSmFcts says
Not sure if you meant it this way, but I for one do not think farmers are dumb. I say this as a wannabe tomato grower (in containers no less). It ain't that easy. And experience counts too. One needs good memory for that.
JamesWimberley says
It's a prejudice among non-farmers, not an observation. I thought I made it clear that I do not buy the just-so story, at least as applied to intelligence, though there just may be something in it for other character traits. The original domestication of crops would have required a lot of intelligence. Wheat and maize have far from simple histories..
Against that, most agricultural labourers throughout history and pre-history have had very little choice about what to do and when, and innovation has been usually a very bad idea.
NCGatSmFcts says
Okay, I figured as much.
Also I misspoke — growing in containers is actually harder, not easier.
It is one of the more bizarre prejudices. Thirty years after Cesar and we are in the same place, basically. Amazing, in a bad way.
paulwallich says
The Flynn Effect (monotonic longterm rise in raw scores) pretty much tells you that IQ is a lousy measure. But Some People still keep trying to base complex arguments on faction-of-a-standard-deviation differences between groups. You gotta wonder about their own psychological makeup.
You also gotta wonder about the people who thought that geneticists as a profession could remain politically disengaged in an increasingly winnner-take-all culture where dodgy genetic data is becoming every more widely available.
Barry_D says
One of the things about that is that ~1/3 of the alleged difference between blacks and whites disappeared in 30 years, which happened to be a 30 year period of great improvement in civil rights and access to material goods among blacks. By the Charles Murray theory, this is inexplicable.
Adding on to the lead exposure, just imagine what childhood was like for the 25th percentile SES black child in 1950, vs. 1980. My guess is that nutrition improved a lot, and exposure to pollution and disease dropped a lot.
paulwallich says
Not just the physical and social issues, but also the acculturation. Although we've progressed a lot from the days when intelligence tests included questions about sports (and were used to "prove" that recent immigrants were dumber than the previous cohorts) there's still a fair amount of cultural baggage to such tests — including the experience of taking standardized tests on a regular basis. (As a privileged white kid in the 60s, I started learning about test-taking in general by the beginning of first grade, and the standardized kind by third; I doubt a poor black kid would have had the same experience.)