A Reason for Everything: Natural Selection and the British Imagination

by Marek Kohn

400pp, Faber, £20



Anyone who has read Richard Dawkins knows that one of the attractions of scientific belief is beauty. To understand the logical necessities of how the world moves and changes is a pleasure almost as keen as music, to which mathematics is related. But it is a very rare soul who is moved to purely contemplative raptures: music has passion as well as order in it; and science is one of the most emotional things anyone can do. Scientists tend no more than musicians to harmonious lives or balanced personalities. Very great scientists, as Marek Kohn makes clear, are often men with no judgment at all outside their work.

Of the six British Darwinists who are the focus of this study, two were more or less monsters; two were consumed in their old age by pet theories; only John Maynard Smith and Richard Dawkins are people you would actually want a conversation with, rather than a lecture from; and Maynard Smith, alas, died last year.

Kohn is one of the best science writers we have. He has found here a fascinating subject: the development of Darwinist thought in Britain over 100 years, which he treats with balance and lucidity, illuminated by a lovely turn of phrase - one of his cranky genius subjects "defies casual admiration". This was RA Fisher, who once clenched his fist in rage at a subordinate while he was holding a mouse, which was crushed to death. "See what you made me do!" he shouted at his human victim, and threw the mouse corpse out of a window. Still, he grinned and forgot the matter when he saw the assistant pull a face. Kohn has been a scientist himself, and in his previous book actually produced a possible story of how and why the human brain evolved. He studied under one of his subjects, John Maynard Smith, who appears as the most attractive of the scientists here.

Kohn's knowledge of how science works is backed by a rich store of anecdotes about what scientists actually do: my favourite has the young Desmond Morris at supper at a conference in Paris in 1954, asking why his hosts, Professor Haldane and his wife, Dr Helen Spurway, are avoiding the other stars of the occasion, Professor and Frau Lorenz. "What's the matter?" he asked. "I'll tell you what the matter is," replied Dr Spurway: "I've been fucked by Konrad Lorenz." Lorenz was a Nazi, Haldane a Stalinist who joined the party after visiting Russia at the height of the purges - he was impressed by the reverence with which they treated intellectuals. Kohn introduces one scientist still more loathsome, Otmar von Verschuer, a German who had studied twins using materials supplied from Auschwitz by his friend Josef Mengele; and whose rehabilitation after the war was supported by the devout Anglican RA Fisher. But Kohn is never indignant. He lays out the facts judiciously, with reverence for the extraordinary things that these men discovered. Besides, he makes it very clear that they were deeply embedded in the societies around them; and the sometimes grotesque political and social beliefs of the great Darwinists were as much a product of the arrogance of the British ruling classes as of the arrogance of science. Both of the party members in this story were Etonians.

Although science is meant to be an international pursuit, accessible to everyone, there are national schools within it; and this is nowhere more true than in evolutionary biology. The story Kohn tells is of the rise of the Oxford school, to which almost everything seems like an adaptation. These are the men reviled by Steven Jay Gould as "Darwinian fundamentalists". They believed, in the words of Kohn's title, that there was "a reason for everything" and this reason must be natural selection. It's easy to underestimate the ambition of this project because most of us still think of evolution as an explanation for the variety of living things in the world. But the ambition of the Oxford school has been to make natural selection a reason for everything - for all the actions in the world, as well as all the actors. By the end of the book, even the colours of the leaves on autumn trees around the grave of Bill Hamilton have been given a meaning by evolution - they are so vivid in order to warn parasites that the tree is healthy enough to repel them.

This kind of reasoning reveals two of the characteristics of the school that so infuriate outsiders. The first, and one of the foundations of its success, is a rigorously statistical approach. The individual simply does not exist from the point of view of natural selection. This is hard to grasp. Since we have evolved as members of a social species, whose fate is influenced by our places in the group, so we naturally take the world personally. Perhaps the deepest conflict between Darwinism and religion lies in Jesus's assertion that "not a sparrow falls" without God noticing and caring. Billions of sparrows must fall to alter the course of history by the width of one downy breast feather, says the evolutionist. This perspective has a morally disorienting effect.

There was a slogan of the early environmentalists, that one should think globally and act locally. Where evolution is concerned, it should be turned on its head. Attempts to think about humans as a global species lead almost at once to disastrous global ideologies - Nazism, communism, fanatical atheism, or even the cloudy eugenic fantasies of Hamilton, whose fears were focused on hospitals, rather than on Jews, evangelicals or the bourgeoisie. Hamilton, though almost the most eccentric of the major figures here, is also one of the sanest and most lovable, because he really did regard himself as a member of the species he was studying. He never for a moment supposed that he himself could be freed from the tyranny of his genes.

The leaves around his grave, however, if they really are the trees' message to gall wasps not to bother laying their eggs there, reveal another disturbing aspect of natural selection. This is that meaning comes into the world before anything that might be said to understand it. The relationship between the vivid red colour of the dying leaves, and the health of the tree that produces them, is neither arbitrary nor conventional. Obviously, neither tree nor wasp can think in any interesting sense. Yet they are exchanging information about the world, and they might be said to be processing it, since their behaviour is certainly affected by it.

The corollary is that we must be doing the same, almost all the time. Our mental life is in this perspective almost entirely unconscious and emotional. Evolutionary biologists came late to the discovery that the heart has its reasons, of which reason knows nothing. But if their research tells us anything about humans, it is that we might some day be able to analyse and reconstruct the workings of the heart, and discover exactly what they are meant to do. It is a real triumph of Kohn's to have opened the hearts and unhidden the reasoning of the men that he writes about.

· Andrew Brown's book In the Beginning Was the Worm: Finding the Secrets of Life in a Tiny Hermaphrodite is published by Pocket Books.