Place of genes in achievement

Press, 1 June 1977, Page 16

Place of genes in achievement

The ‘Economist’, London, reports more evidence that genetic endowment limits, without destroying, the prospects for social change.

There are times when it is important to clump down the middle of the road: to restate what most peonle always thought was obvious and what the most bitter opponents, at each other’s throats, would ultimately claim they had never disputed. In this case, heredity and environment both play an important part in determining individual make-up and achievement. The occasion for promoting this momentous cliche is the publicity given by Professor Hans Eysenck recently to some American research published last year. This purports to demonstrate that earnings are determined 48 per cent by genetic inheritance". 6 per cent by family environment, and 46 per cent by other environmental factors — among which school plays only a small part. Professor Paul Taubman of Pennsylvania University examined information about 2468 white, male twins bom between 1917 and 1927 who served in the United States Army in the Second World War. In 1973. when all of them were roughlv 50 years old. he looked at their incomes.

If they had been just random pairs of white American males no correlation between their incomes would have been found. But for the pairs of identical twins the correlation was substantial (54 per cent), whereas for the nonidentical twins it was 30 per cent. Each pair of twins was assumed to have the same family environment So Professor Taubman concludes that the 24 per cent difference must be due to the fact that identical twins share ail their genes whereas non-

identical twins share only half their genes. That means that the full-genetic contribution to income is twice 24 per cent — 48 per cent.

This is the latest gobbet to be thrown into the heredity-versus-environment debate that was long ago hauled out of the laboratory and into politics. Roughly speaking, left-of-centre interventionists have leaned towards environment. The laisser-faire-minded on the right-of-centre tend to give more weight to heredity. Mr Taubman’s work falls into line with other studies on twins, which suggest that the intelligence correlation among identical twins may be even higher (70 per cent) then for earnings. identical twins also have similar personalities, attitudes and abilities to make decisions. In strict theory, as Mr Taubman himself admits, the findings about this particular bunch of American twins cannot be taken to apply generally. But as most of the relationships he demonstrates (say, between schooling, father’s income and the achievement of individuals) have been found in other Western industrial societies, he has probably got it right. So do Mr Taubman’s conclusions mean that the whole drift of American and British social policy since the Second World War has been misguided? Not so simple. An intelligent twin or non-twin can have his earning power blighted by a slum-family, slum-school, slum-back-street education. A man as dim as a Toc-H lamp can still do pretty well in life if he is blasted into New College via Winchester. So came the first great

push to mass-education schools. It failed to achieve the hoped-for miracles. Attention then zoomed in on preschool children and educating parents in parenthood. But the benefits of such headstart programmes also wore off rapidly. Upgraded housing . . . income maintenance . . . more jobs. In Britain, a Tory’ minister of social services (1970-74), Sir Keith Joseph, began research (still continuing) into the “cycle of deprivation.” Great society reformers created the impression, while not believing in it themselves, that all people could be tinkered into being equal. Outraged, Professor Eysenck I

and others have campaigned to reverse that impression. They have been right to do so: offering equality of opportunity to the inherently unequal could, eventually, become a bitterly bad joke. Much better in the light of their evidence to concentrate on income support to help the less well endowed lead a decent life. The whole man, however, is neither wholly Professor Eysenck’s nor is he wholly his opponents’. He is largely, to start with and for ever, what he is bom. But he is then partly also what his parents, his schools and his society give him the chance to be.