Travels in conceptual space

Peter Bowler praises an authoritative account of the evolution of Darwin's genius; Charles Darwin: Voyaging Janet Browne Jonathan Cape £25

Publishers must believe that the public has an unlimited curiosity about the life of Charles Darwin. At least four biographies have appeared in the last five years, and they are getting bigger. Janet Browne's is shorter than Adrian Desmond and James Moore's much publicised 1991 account (600 as opposed to 800 pages), but she takes the story only as far as 1856. A second volume will deal with the Origin of Species and the subsequent debates.

One would hardly expect a former editor of the Darwin correspondence (nine volumes in print) to deal lightly with her subject. This is intended as a definitive biography, at least in terms of the level of detail in which Darwin's life is explored. Yet in a sense there can never be a definitive account, because his theory of evolution still arouses controversies which affect our judgement. The differences between Browne's interpretation and that offered by Desmond and Moore reveal the extent to which Darwin's life has become a battleground for historians. What you get is what the author wants you to believe was important in shaping his ideas about evolution.

Browne's is a more conventional biography, written in a more relaxed style. It lacks the underlying agenda of Desmond and Moore, which sparked a good deal of controversy. They flitted frenetically from Chartist riots to Darwin's personal traumas, with the aim of convincing us that his ideas were shaped by his social environment. Browne pays more attention to Darwin's scientific life, less to the surrounding ferment of social debate. She is not oblivious to the parallels between the theory of natural selection and the competitive ethos of Victorian capitalism. But she is more interested in Darwin's efforts to apply his theoretical insights to his researches in natural history.

The problem with stressing the congruence between the "survival of the fittest" and the free-enterprise system is that so many others were exposed to the same influence. The philosopher Herbert Spencer, who actually coined the term, also visualized competition as the motor of progress. Darwin did something more: he turned that insight into a theory capable of addressing a host of technical issues in ways that modern biologists still find fruitful.

Browne explores the origins of Darwin's theory by taking account of both his cultural environment and his biological discoveries. She draws on the wealth of his surviving notes and letters, and on the experience of the scholars who have spent their careers interpreting this evidence. Where Desmond and Moore challenged the "Darwin industry" to confront the claim that scientific knowledge is a social construct, Browne offers a synthesis of the internal and external approaches to the history of science.

As the subtitle indicates, the highlight of Darwin's early career was his voyage aboard the survey-vessel HMS Beagle from 1831 to 1836. The voyage transformed Darwin's life in more ways than one. He returned with a determination to become a full-time scientist (not quite a professional, since unlike his disciple T H Huxley he did not have to earn a living from his science). Publication of his geological results gave him the start he needed in the London scientific community. Behind the scenes, his observations had convinced him that evolution had occurred, and he had began to think about how the process might work.

He had now begun the painful transition from belief in a benevolent Creator to a theory in which struggle and death were themselves creative forces. No one doubts that living in a society based on individual competition helped him to move in this direction. But even before he read Malthus on population-pressure - conventionally regarded as the source of the struggle metaphor - he had been forced towards a harsher image of nature by his observations in South America. If the Galapagos Islands provided the key evidence for divergent evolution, mainland South America showed him species competing for territory. Here too there were human parallels. He was caught up in a war of extermination being waged by European settlers against the natives. At another level, the very presence of the Beagle in South American waters symbolized Britain's efforts to dominate world trade.

Darwin's voyage in geographical space thus shaped his voyage in the conceptual space of science and social imagery. The metaphor of the "struggle for existence" emerged not just from the ethos of Victorian capitalism, but also from Britain's move towards global dominance. Darwin's theory survived as a cultural icon well into the 20th century because his bio-geography was modelled on imperialism as much as his evolutionary mechanism was modelled on capitalism. By focusing on the Beagle voyage, Browne shows the range of ideological and scientific influences at work.

At the same time, she reveals Darwin's reluctance to give up his early faith in a common humanity linking all races of mankind. His experiences with the natives of Tierra del Fuego convinced him that the only difference between a "savage" and a civilized person was education. We are all savages under the skin - a view which helped him to contemplate the possibility that we might be evolved from animals. After thinking hard about this prospect in the late 1830s, he put it aside to concentrate on biology. Browne's next volume will have to confront the fact that when he returned to the subject in later life, he had succumbed to the lure of biological determinism. Savage races became relics of the evolutionary past, locked into permanent inferiority.

Historians will almost certainly adopt Browne's account as the most authoritative survey of Darwin's life and work. Ordinary readers will appreciate its efforts to reveal the complex process of scientific creativity.

Peter Bowler is Professor of Social Anthropology at The Queen's University, Belfast