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Collaboration between brains matter more than individual intelligence

My Times column on the implications of genetic evolution since races diverged:

Is it necessary to believe that racial differences are small and skin-deep in order not to be a racist? For the first half of the last century, science generally exaggerated stereotypes of racial difference in behaviour and assumed that they were innate and immutable. For the second half, science generally asserted that there were no differences — save the obvious, visible ones — and used this argument to combat prejudice.

Yet that second premise is becoming increasingly untenable in the genomic era as more details emerge of human genetic diversity. We will have to justify equal treatment using something other than identity of nature. Fortunately, it’s easily done.

Human evolution did not cease thousands of years ago; it has been “recent, copious and regional”, in the words of Nicholas Wade, a veteran New York Times science writer and the author of A Troublesome Inheritancean eloquent but disturbing book on genes, race and human history, which was published last week.

In the past 30,000 years — after humanity split into different races — all sorts of genetic change has happened through natural selection: lactose tolerance developed in response to dairy farming in Europe and parts of Africa; physiological adaptations for high altitude emerged in Tibetans; malaria resistance spread throughout Africa and the Mediterranean; a gene for sweat glands, ear wax and hair changed in China.

One estimate is that about 14 per cent of the human genome — 722 regions containing 2,465 genes — has been affected by so-called “selective sweeps” (whereby a gene mutation brings an advantage and replaces other versions in the population) in one race or another. The frequencies of gene variants have shown rapid change in these places. In many places, the affected genes are active mostly in the brain. As Wade puts it: “These findings establish the obvious truth that brain genes do not lie in some special category exempt from natural selection.”

Perhaps people of Ashkenazi Jewish descent have high average IQs because for centuries their ancestors worked almost exclusively in professions such as money-lending, where exceptional literacy and numeracy were rewarded with greater fecundity. Or perhaps Chinese people show greater conformity because for centuries those who could stomach Confucian rote-learning and obedience got to have more surviving children. These are no more far-fetched arguments than to suppose that ancestral Inuit with genetic adaptations for coping with the cold had more offspring.

Nor is it implausible that over millennia of settled, agricultural and urban living, with the execution or ostracism of “skull-cracker” misfits, selection took place for tameness in the natives of Europe or India compared with say, New Guinea or the Amazon. Thanks to “soft sweeps” — where multiple existing gene variants change in frequency — evolution can work a lot faster than we used to think. Starting in the 1960s, a Russian fur farmer transformed silver foxes from fearsome, fierce, wild animals into affectionate, floppy-eared, piebald pets in only 35 generations simply by breeding from those that were least fearsome.

So Wade is absolutely right that the old assumption that human behaviour did not evolve much after the divergence of human races at the end of the old Stone Age has to be wrong. The comforting message that biologists sent to social scientists in the 1960s — that they were sure there was no biological basis for race, which could instead be regarded as a social construct — is bunk.

True, the boundaries of races are blurred, and the differences between individuals dwarf those between average members of different races, but differences there are, and not just in skin pigment. The more we look, the more genetic variation we will find between races, as well as between individuals, so we had better get ready to deal with such discoveries, if only for medical reasons. Some diseases afflict certain races more; some drugs work differently in different races.

However, I part company with the next step in Wade’s argument. He tries to explain too much of human history by gene changes. The industrial revolution started in Europe and not China, he suggests, partly because Europe had been preconditioned by genetic evolution for the sort of economic openness that sparked accelerating innovation.

This is based on the work of the historian Gregory Clark (like Wade, an expatriate Briton in America who has written a fascinating new book about social mobility called The Son Also Rises). The evidence from the history of surnames, Clark says, “confirms a permanent selection in pre-industrial England for the genes of the economically successful, and against the genes of the poor and criminal”. Clark finds that, more than in China, for centuries literate, entrepreneurial Europeans had been out-breeding poorer ones, their genes cascading down into the working class through downward mobility.

So yes, there would have been genetic change in European society as certain types of personality had more offspring. But surely this was not anywhere near fast or large enough to spark the industrial revolution, let alone as important as factors such as the harnessing of fossil fuels or the invention of inclusive institutions and opening up to trade. Just look at how quickly attitudes to homosexuality, say, have changed within a lifetime, with no time for gene changes.

It may be harder to build and run a modern consumer society from scratch using only people whose ancestors were hunter-gathering for most of the past 30,000 years (native Australians, say) than by using only people whose ancestors experienced farming, cities, diseases, alcohol and literacy. But it would be far from impossible with the right institutions.

There is a big reason that racial differences in mental capacity will not matter a jot, however many we find. Human achievement is not, despite what professors like to think, the work of brilliant individuals. It is a collective phenomenon. Every technology, every idea, every institution is a combination of many people’s contributions. There is no single human being on the planet, as Leonard Read famously pointed out, who knows how to make a pencil, let alone the internet, the economy or the government.

The average IQ of a group, a team or a race matters little, if at all. What counts is how well they communicate, collaborate and exchange ideas. Give me a hundred thickos who talk to each other, rather than a hundred clever-clogs who don’t. This collaboration is surely the true secret of human achievement and the true reason that race does not count, not because we are all identical inside our skulls.

By Matt Ridley | Tagged:  rational-optimist  the-times