In Memory of Bill Hamilton

In Darwin's footsteps by Andrew Brown

Researchers are poised to announce the decoding of the human genome and hail the greatest scientific breakthrough of our age. But a quiet, insect-loving Oxford academic did much more to reveal how genes shape our life and behaviour. Andrew Brown on William Hamilton, the unsung genius of genetics.

Any day now, one of two fiercely competing teams will announce that they have sequenced the human genome, and that this has been the greatest breakthrough in scientific understanding since Darwin; or perhaps even Newton, Copernicus, or the Big Bang. But one man, a scientist whom hardly anyone has heard of, did far more than the whole of the human genome project to discover why genes matter and how they might shape our destiny.

The human genome project is designed to discover the precise composition of tens of thousands of genes. Bill Hamilton, apparently a shy and forgetful Oxford don, was not concerned with what genes are made of, but with what they do, and how their interplay can shape the world. He tried to give biological answers to the large questions, such as, why is there sex? Why do we grow old? And, in the world that made his name, why do animals sacrifice their own interests for the good of others?

Hamilton was born in Cairo in 1936, the son of a civil engineer working in the Middle East, and died in April this year after contracting malaria on a Quixotic mission to collect chimpanzee faeces in the Congolese jungle. It was a characteristically brave and direct attempt to stand up an unpopular theory, in this case that the Aids epidemic was caused by a polio vaccination programme. He never shrank from physical effort or danger. As a teenager he blew the tips off two of his fingers while messing around with explosives (his father was a civil engineer). On a field trip in the Amazon he once jumped off the side of his boat to plug a leak with his finger, explaining afterwards that the ferocity of piranhas was much over-rated. He refused to wear a bicycle helmet even after being pitched through the windscreen of a car as he hurtled round Oxford.

Those are things that made him loved. What will ensure his fame was that in two papers of almost impenetrable mathematics published in 1964, he discovered the selfish gene. In the papers, he expressed mathematically the ways in which self-sacrificing behaviour among individual creatures would spread if it were caused by a gene which was shared by lots of relatives who in their turn benefited from the self-sacrifice.

It is less often noticed that the same theory explains with heartless and unanswerable elegance how selfish or gratuitously cruel impulses may spread and establish themselves if they turn out be more profitable to their bearer's genes than kindness would. Other great biologists, notably JBS Haldane, had seen that something of the sort must be true. Indeed, Haldane had turned a crude version of the idea into a pub joke. When asked, "Should I lay down my life for my brothers?", Haldane replied, "Yes, for three brothers, five uncles or nine first cousins."

But Hamilton gave this vague intuition solid mathematical backing and turned it into something other scientists could use to make predictions about the way any animal or even plant could behave and feel towards members of its own species.

It took some time for the implications of his discovery to sink in. They didn't hit the non-specialist public until the early 70s, when they formed part of the framework of EO Wilson's Sociobiology and Richard Dawkins's The Selfish Gene. Though they are now regarded as perhaps the most important development of evolutionary theory since Darwin, Hamilton's interests were almost incomprehensible to his teachers when he was a postgraduate student at the London School of Economics and University College London.

Years later, Hamilton wrote: "I am afraid I still feel rather resentful about the matter in a general way. I would have hoped that the purpose of Haldane's aphorism was precisely to encourage young men to take up the study of what he considered an important topic. Yet at University College, surrounded presumably by a number of scientists who had been primed in this way, all my own attempts to tell people that a principle of this kind was needed in biology and this was what I was working on were met by the sourest rebuffs - words to the effect that I was wasting my time, there was no such thing as genetic altruism, or, at best, total disinterest.

"I suppose it is understandable that a disciple without a master must expect a hard time and that statements that seem significant or humorous according to the hearer's mood when uttered by a famous scientist seem to be heretical and ridiculous pretension when uttered by a detached graduate student, but I can't help feeling that it is wrong that this should be so in a university. I also have in mind that I was a rather retiring kind of student who preferred to withdraw from people who found me ridiculous rather than argue back."

This came from a letter he wrote to John Maynard Smith, an older and almost equally distinguished biologist who had been one of the earliest champions of his ideas, but from whom he was for some years estranged because he believed that Maynard Smith had granted too much of the credit to Haldane for the ideas that Hamilton later developed. Later, Maynard Smith reproached himself for failing to recognise genius. But it is easy to understand how the student might have been overlooked.

Though he passionately wanted recognition, he did not care at all for cities, and at times appeared to have an overwhelming longing for absence. There is a note of aching nostalgia for the wilderness which breaks again and again through the story of his early struggles. As a poor student he walked everywhere he could: "I wanted to conjure and recreate somehow, below the bricks and mortar around me, the marshy fields that had once been there, the streams dividing them, and the heaths beneath - to seek, in short, the elemental forces underlying the city. Even a lonely child crying on the street did not tug my heart as hard as a bracken fern when I saw it, for example, in the valley of the stream once called the Fleet."

It was not just plants that moved him deeply. A passion for insects ran through his entire life. When he got his first job as a biologist, and moved to a bedsit near Windsor Great Park, it seemed to him a delightful bonus that it was infested with minute bacon beetles: "I should explain that I am generally fond of indoor insects, think of them like pets and generally see an advantage over pets in that they don't need to be fed." In some of his speculations about eugenics, it can seem that he cared as little for humans as he might for insects; but if that's true it should be said that he clearly loved insects. It would be more just to say that he thought nature cared as little for mankind as for insects, as any honest naturalist must do.

Even as a feted professor at Oxford, Hamilton had a quality of absence or self-effacement that was extraordinary. He spoke quietly, almost as if he were hesitant to remind you of something you already knew: my notes from talking to him in his office are almost incoherent, a little from awe, some perhaps from stupidity, but also because he seemed quite as happy to sit in silence as to talk. He was a tall man, extremely handsome, but carried himself like a hunter who would rather observe than be noticed.

Partly as a result of this he was almost unbearably lonely and isolated when he worked on his first papers. "Although supervised at the Galton Laboratory for two years, I never had a desk there - I think virtually no one I passed in the corridors or sat with in the library knew my name or what I was doing - most of the time I was extremely lonely," he wrote, years later, in the introduction to his collected papers. These make one of the most extraordinary books of the century, for they contain not just the science that gave him his place in history, but, in their prefaces, an autobiography in fragments written with an extraordinary clarity, warmth and intimacy.

If you stand in the Sanger Centre outside Cambridge and watch the display over the receptionist's desk, as it flickers a constantly moving line of letters representing the DNA sequence of the human genome as it is decoded, the letters might represent anything. Without huge training it is impossible to grasp their significance or why they excite people. But Hamilton's passions, refracted through his writing, never lacked significance or excitement. In his essays there is no gap between theoretical and emotional significance. He wrote as if the human microcosm and the macrocosm of all biology were transparently linked.

We don't think of scientists as particularly romantic figures, yet Hamilton's autobiographical fragments in Narrow Roads are intensely romantic in their sensibilities, because he sees humanity as essentially tragic and divided against itself. "As I write these words, even so as to be able to write them, I am pretending to a unity that, deep inside myself, I now know does not exist. I am fundamentally mixed, male with female, parent with offspring, warring segments of chromosome that interlocked in strife millions of years before Europe existed or saw any of the human violence that became later, for sure, embedded in my ancestry."

When I discovered his collected papers, I found them enchanting, and wrote a book off the back of the experience. And there is no doubt, from the fervour and warmth of his obituaries, that people who worked with him came to love him as well as to admire him.

The most moving quality in him, I think, was an extraordinary optimism which seemed to contradict everything in his professional life: as a biologist, his efforts were directed at showing that all hope, all passions of any sort, perhaps, were an illusion which go to serve the purposes of the genes. We think we act for our own reasons; but in reality we are merely keeping the score in a millennial battle of chromosomal fragments. This was the message of his science, which has been spread steadily around the world since 1964. Yet he believed in the reality of altruism. Indeed his death was in one sense a testimony to this faith. Perhaps he wrote his own epitaph when writing about his father, an engineer who built a road through Kurdistan which has been almost entirely destroyed in wars since then: "The effort that he made - not in the least made on behalf of kin, or expecting any tangible return - nevertheless made changes. The effect of true altruism like this is never lost completely."

Andrew Brown is the author of The Darwin Wars, published by Simon & Schuster. For futher information visit http://www.darwinwars.com