Race, genes and recent evolution

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 Inheritance, an 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.