There are few more contentious topics in science than the question of whether genes determine human intelligence – particularly whether different “races” have different levels of intelligence.
This subject has often been characterised by prejudiced views and flawed methods of investigation – and by media coverage that fails to distinguish science from pseudo-science.
So when I heard that Channel 4 was beginning its new “Race: Science’s Last Taboo” season with a documentary about this topic, I was preparing myself for more of the same.
In fact the programme, narrated by Somalian-British journalist Rageh Omaar, is an excellent piece of science journalism, and a must for anyone interested in this controversial subject.
Omaar begins with an accepted fact – that black students generally have a poorer performance in standard IQ tests. He asks what the reason might be for this difference.
For US academics Richard Hernstein and Charles Murray, authors of the Bell Curve, or the British psychologist Richard Lynn, who is interviewed in this programme, the explanation is simple – black people are less intelligent because they are genetically different to whites.
It was after reading Lynn’s book on the subject that Nobel Prize winner James Watson, co-discoverer of the double helix structure of DNA, made his infamous statement in 2008 about the intellectual inferiority of black people.
This led to his dismissal as head of the prestigious Cold Spring Harbor Laboratory in New York.
Another Nobel Prize winner mentioned is William Shockley, co-inventor of the transistor, who held even more racist views on this subject. He also believed than anyone with an IQ below 100 should be encouraged to undergo sterilisation.
Omaar believes that, while we may abhor the views of such individuals, we still need to engage critically with their arguments, coming as they do from such “brilliant scientists”.
I would agree with the need for critical engagement. But just because someone has a Nobel Prize in one area of science does not at all exclude the possibility that they may be ignorant and misguided in another.
The scientific methods used in both The Bell Curve and Lynn’s book have been shown by numerous critical studies to be deeply flawed.
Even so, at one point in the programme I was beginning to wonder when we were going to hear some of the counter-arguments against the racist ones.
When they do finally appear, the arguments against the idea that black people are less intelligent than whites and that IQ tests measure a fixed entity called intelligence are very powerful ones indeed.
IQ tests were originally designed by Alfred Binet as a progressive method to identify children with learning difficulties.
They were intended not to stigmatise but to help such children overcome their difficulties. However, in the hands of US eugenicists like Henry Goddard, they rapidly became used as a way to group people into fixed categories of intelligence, with such terms as “normal”, “idiots”, and “imbeciles”.
Such rigid labelling formed the basis of the 11-plus system that excluded many ordinary children from a proper education.
In many states in the US it was used as the justification for laws permitting the enforced sterilisation of people identified as “subnormal” by the tests. Many of these laws were only repealed in the 1970s.
But do IQ tests even measure intelligence? As a means of understanding more about these tests, Omaar sits one himself.
It becomes clear that many of the questions test culturally specific general knowledge, such as questions about British history or politics.
Even the supposedly more neutral problem-solving type of questions assume a familiarity with puzzles and number games that would be most familiar to children from white, middle class backgrounds.
It is perhaps not so surprising then that black students, who are more likely to come from working class backgrounds, and be less in touch with the culture of “white society”, do not do as well in IQ tests.
What about the argument that intelligence is genetically determined and that the “IQ gap” between blacks and whites is a result of genetic
differences between the races?
This is a view strongly advocated by Professor J Philippe Rushton, of the University of Western Ontario in Canada. Yet when asked in this programme to name such genes, he is unable to.
This is not surprising. All serious genetic studies indicate that something as complex as human intelligence is almost certainly due to a highly complex mixture of genetic and environmental factors.
This means it is almost certainly nonsense to talk about genes “determining” intelligence.
Another problem is the very idea that “black” or “white” is anything more than skin deep.
Racists seize upon superficial features like the colour of someone’s skin, the shape of their nose or the curliness of their hair.
Yet as Professor Steve Jones says in this programme, the most striking thing about human beings compared to many other species is how similar we all are genetically.
The findings of the Human Genome Project have shown that humans have 99.9 percent genetic similarity, and that there is greater genetic variation within each “race” than there is between “races”.
Meanwhile in the US, many black people have gene variants thought to be typically “European” for the simple reason that they have one or more white ancestors.
This leads to an interesting point, made in this programme by Professor Richard Nisbett.
If it were really true that whites are genetically more intelligent than blacks, then the most high-achieving blacks ought to be those with the most percentage of “white” genes. In fact nothing of the sort is found.
Refuting the argument that differences in IQ test performance reflect genetic differences between races still leaves us with the question of how to solve the problem of the “IQ gap”.
One argument that has surfaced recently is the idea that black parents should be doing more to encourage their children to value learning and academic achievement.
Such an accusation is easy to make. Yet as Rema Reynolds, a black psychology professor at Azusa Pacific University, says, black working class parents often have far less time due to working all hours to make ends meet.
They also often have a poorer educational background themselves. And so they find it hard to offer the sort of support to their children that is provided by many white middle class parents to theirs.
So what can be done to readdress this imbalance, and how likely is it to have an effect? Two very positive examples are highlighted in the programme. The first is South Africa.
Omaar interviews Dr Thebe Melupe, who is one of the leading black astronomers in the country. Melupe believes himself fortunate to have graduated from school the year that Nelson Mandela was released from prison.
Under the apartheid regime he would have been denied such a chance to excel since educated black men were viewed as a threat to the system.
Another example provided is that of the Hostos-Lincoln Academy in New York. Situated in the South Bronx, the mainly poor black and Latino students would not normally be expected to be high academic achievers.
Yet the graduation rate at this school is 90 percent, compared to an average of around 50 percent across state schools in New York. Many of its students go on to top US universities.
The school does not label the students as failures before they start. Instead its ethos seems to be that everyone is a potential high achiever.
Learning is made exciting by innovative teaching methods and an emphasis on the importance of theatre and other cultural events in which the students all take part.
In Britain, the current biggest challenge for working class children and those from ethnic minorities is the fact that the government is threatening to slash the education budget.
What emerges from this documentary is that if we truly want to allow children of all classes and so-called races the chance to achieve their potential, and thus demonstrate their “intelligence”, we have to make education exciting and stimulating.
This requires vastly more resources in teaching, not less.
The Race: Science’s Last Taboo season can be seen at » www.channel4.com/4od. Subsequent progammes in the series are shown on Channel 4 on Mondays for the following four weeks
John Parrington is a lecturer in cellular and molecular pharmacology at the University of Oxford