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A Reason for Everything: Natural selection and the English imagination by Marek Kohn, Faber and Faber, £20, ISBN 0571223923

IN 1978 the American palaeontologist Stephen Jay Gould and his countryman Richard Lewontin, a geneticist, were invited by the English biologist John Maynard Smith to a Royal Society meeting in London. There they gave a presentation attacking what they saw as the British “hang-up” of adaptationism.

Adaptationism is the insistence that evolution is driven by the need for organisms to adapt successfully to their environments or die. Advocates of the extreme form of this position assume that there is an adaptive reason for everything we see in an organism’s behaviour and structure, or, to put it more cruelly, that evolutionary theory is a series of Just So stories, however involved. Gould and Lewontin’s claim was that the design of organisms was not driven by the environment at all: structures and behaviours came from a combination of compromises, happy accidents and internal motors that to some extent dictated structure and form, even when the results were maladaptive or practically illogical.

In A Reason for Everything, Marek Kohn has set himself the task of defending the British school from this attack. And in a rather adaptationist fashion, he has decided to do it not just by examining the theories and forms of the arguments at play but biographically, by taking a look at the characters involved, their beliefs, their personalities, their passions and their politics. The result is a marvellous book that has reawakened my excitement in evolutionary biology, on the wane ever since I became lost in the intricacies of the Maynard Smith versus Gould controversy which, as an amateur observer, I’d started to find more than a little unfathomable.

Kohn is an excellent science writer, combining concision, variation and erudition with a novelist’s ability to draw character. Constructed as a series of biographical essays focusing on key players – Alfred Russel Wallace, Ronald Aylmer Fisher, J. B. S. Haldane, E. B. Ford, John Maynard Smith, Bill Hamilton and Richard Dawkins (Darwin himself is deliberately and sensibly excluded) – Kohn allows the story to unfold more or less of its own accord in interwoven eddies, not unlike evolution itself.

Kohn’s strength is that he draws everything in the round and still manages to convince that for all its faults, switchbacks and curiosities there is something not only attractive and rigorous but also fundamentally true about the adaptationism approach. Goodness me, it’s almost enough to make you proud to be British. Or English, at any rate.