Darwin and the 'heredity' peer

Mary Warnock is disturbed by a life of Francis Galton, the father of eugenics.

The trouble with the biography of a polymath such as Francis Galton is that in our fragmented world, where barriers surround what we think we need to understand, very few people will be interested in, or capable of understanding, the whole of the subject matter. Galton was a splendid example of the Victorian all-rounder. He was destined by his family to be a doctor but broke off his medical studies to go to Cambridge to read for the mathematical tripos. While he did not do very well in the tripos, mathematics was his passion. The thread running through all his work was his determination to make evidence quantifiable. In an early article he even tried to prove statistically the inefficacy of prayer, pointing out, for instance, that monarchs were the most short-lived of all humans, despite being the most prayed for.

After Cambridge, Galton appears to have dropped out, travelling widely, but not doing much else. It was his great enthusiasm not merely for travel (especially in Africa) but also for accurate charting of both land and sky that brought him back into mainstream science. He became a valued member and later official of the Royal Geographical Society, invented the concept of the anticyclone, and demanded both of himself and other explorers scientifically accurate cartography.

The part of this biography that covers Galton's rise to eminence as a geographer and meteorologist is in many ways the most enjoyable, not least because it records the wonderful rows within the RGS about the merits and demerits of Henry Morton Stanley, thought by some to be nothing but an upstart American journalist, and David Livingstone. However, Galton is best remembered today for his work on heredity and his subsequent enthusiasm for "eugenics", another word that he coined.

The publication of Darwin's On the Origin of Species in 1859 was a turning point in Galton's intellectual life. In his Memories, he says that he "devoured its contents and assimilated them as fast as they were devoured, a fact that may be ascribed to an hereditary bent of mind that both its illustrious author and myself have inherited from our common grandfather, Dr Erasmus Darwin". He was acutely aware of the intellectual supremacy of his own family, and in his first book after reading Darwin, Hereditary Genius , sets out to show the probability of eminent fathers having eminent sons. Darwin agreed with his cousin that "education and environment produce only a small effect on the mind of anyone... and most of our qualities are innate".

Darwin himself had shown empirically that natural selection ensures the inheritance of characteristics in all species that will best enable them to survive in their environment. But he had not been able to discover the mechanism responsible for this phenomenon. Indeed, there was a problem at the very heart of his theory. If each parent passed on half of its characteristics to the offspring, and these characteristics were mingled together, how was it possible that the characteristics did not simply get watered down in the offspring? Galton understood this problem. Indeed, his own research had made it more acute, for, in order to pursue his vision of characteristics inherited through families, he had to find a way of measuring heritability. Accordingly, he set up what he called an anthropometric laboratory, first as part of the International Health Exhibition at the Royal Horticultural Society in 1884, and then as a freestanding research tool. People who came to the laboratory underwent a variety of measurements and tests, and had to supply details of their families, as far back as they could. It was immensely popular, and Galton accumulated a huge quantity of data that he then had to find a way of analysing. The results showed a tendency for offspring of outstanding parents to "revert to the mean" (another phrase that he coined).

So how could outstanding parents produce outstanding offspring? Why was there not a constant dilution of talent? (Galton had, after all, ruled out any effect that upbringing or parental influence might have on success). To cope with this problem, he had to invent a theory allowing outstanding characteristics to reappear after skipping a generation. But this did not solve the problem: it only obscured it.

Meanwhile, Gregor Mendel, working patiently with his peas in the monastery in Brno, published a paper in 1865, identifying a previously unsuspected mode of transmission of hereditary factors (not yet called genes). He suggested they were not mixed, but separately and randomly passed on, half from the male, half from the female line. This explained why there was no dilution. This paper was not noticed until most of Galton's work was done, and was not generally accepted until 1900.

Galton had become obsessed with eugenics, an interest that went back to his work on hereditary genius. He did not want to eliminate unsatisfactory people from the world, but rather to increase the numbers and enhance the prospects of those of outstanding ability, such as himself and his Darwin cousins (sadly, he had no children of his own). Even if we can think ourselves back into a time when "eugenics" had not acquired the sinister connotations that it has today - a time before the programmes of compulsory sterilisation in the US in the 1920s and 1930s (and in Sweden as late as the 1970s) - it is still astonishing to encounter the confidence with which Galton could divide people into the better and the worse, those who should be encouraged to reproduce and those who should not. Nicholas Wright Gillham defends him, arguing that Galton was simply extrapolating from Darwin's theory of natural selection, and would have been horrified to learn of the uses to which the idea of eugenics has been put. Nevertheless, there remains something inhuman about it, and about Galton.

The story of the attempts to solve the problems thrown up by Darwin's theories, and solve them by means of statistical examination of evidence for evolution, is important in the history of biological science. But it makes for pretty arid reading, as does the uneasy marriage of detailed statistical analysis with outbursts of increasingly gloomy domestic life. But, generally, Gillham writes in an informal, jolly, highly American style. Much of the book is a good read. Where it is not, readers may feel, probably rightly, inclined to blame their own stupidity.

Baroness Warnock was formerly mistress of Girton College, Cambridge.