BOOK REVIEW / Diary of a biophiliac: 'The Diversity of Life' - Edward O Wilson: Allen Lane, 22.50 pounds

ONE NIGHT, camped out in the Amazonian basin, E O Wilson was caught in a ferocious storm that seemed for a few moments to freeze the whole saga of natural evolution in a series of brilliant tableaux. In the flickering lightning he caught glimpses of the awesome intricacy of the rain-forest, its canopied layers and drapes of epiphytes, and imagined the riot of creatures that lived in and on it: palm-vipers curled in orchid roots, bats hunting fruit by smell, a thousand species of butterfly waiting invisibly for the dawn. In a kind of exultancy he thought, too, of the forest regenerating itself, and of the vast web of minute organisms, most of them unnamed, that were already recycling the storm-blown trees. The diversity of life was the saving grace of creation: 'It had eaten the storms - folded them into its genes - and created the world that created us. It holds the world steady.' He wanted to understand it all, yet keep it impenetrable and mysterious. 'Its very strength posed the question: how much force does it take to break the crucible of evolution?'

European writers, reflecting perhaps their own cramped and regimented landscapes, have never felt comfortable celebrating the sheer exuberance, the 'otherness' of nature. That has been the special gift of the New World. In this magnificent book E O Wilson joins the tradition of what could be called 'transcendental materialism' (awe with its feet firmly on the ground) that stretches from Thoreau to Annie Dillard. Those who know Wilson only from his seemingly more deterministic writings on human and animal behaviour may be surprised to find him in such company, but the profusion of nature is his passion too, and one in which his romantic spirit and scientific enthusiasm can work together.

John Berger wrote that 'Art does not imitate nature; it imitates a creation.' Wilson, I suspect, feels the same about biology. It is a study which reflects the profusion and opportunism of its subjects, and which he sees as one of the noble and natural pursuits of that uniquely diverse product of evolution, homo sapiens. And, after the extraordinary fact of life itself, its teeming diversity is the great mystery. Why so many beautiful, ingenious, opportunistic creatures? Why not just one homogeneous green sludge covering the earth?

Wilson pursues the diversification of life from its earliest beginnings more than a billion years ago to the current crisis of man-driven extinction, always looking for connections, always hopeful. He describes the cataclysmic volcanic explosion of Krakatoa in 1883 that wiped out an entire island ecology and whose ripples rolled into Le Havre 32 hours later. But within a year, windblown fungus spores, aphids, grass-seeds, gossamer spiders were recolonising the island; within 40 years it was cloaked by forest.

Krakatoa, like Wilson's Amazonian storm, is a tiny metaphor for nature's resilience. Maybe five times during the past half-billion years, there have been global mass extinctions because of climate change or meteorite strike. On each occasion the fact of genetic error and change, the evolution of new species, and the advance, retreat and regrouping of the old, has enabled the biosphere to survive. Diversity multiplies itself - the new tree providing a niche for a new aphid, which makes food for a newly specialised ladybird . . . It has been going on so long and so successfully that no one has been able to produce even a rough count of the species alive at present. It may be 10 million, it may be 100 million. All that is certain is that they are currently being driven into extinction faster than they are being discovered, burned up in the great pyres of Amazonia, sucked from the continental shelves by factory-ships, poisoned by short-sighted agricultural policies. So interdependent are the creatures in an ecosystem that even the temporary local extinction of a single 'keystone' species can create powerful ripples. When sea-otters were hunted into oblivion along the western American shoreline, there was a vast population explosion of sea-urchins, the otters' main prey. They in turn grazed away the kelp forests which had supported rich colonies of fish, crustaceans and whales, until they created an underwater desert, a 'sea-urchin barren'.

It is another parable, which fortunately has a happy ending after the sea-otter was restored. But in the rain-forest, Wilson estimates, we are irreversibly extinguishing more than 27,000 species a year, a rate which is up to 10,000 times the natural 'background' extinction rate. It is also our own future we are destroying - the possibility of new drugs like the anti-ovarian cancer chemical taxol, discovered in the Pacific yew; of new crop plants like the salt-tolerant salicornias from Mexico. We may even be eliminating vital links in the chains of life that maintain the atmosphere and the fecundity of the seas without the slightest idea of what we are doing.

But Wilson is not just a pragmatist. In a powerful and lyrical last chapter he makes a plea for a new environmental ethic, for a recognition that the rest of creation is where we came from; it is our ancestry, our context. He describes one of our recently discovered fellow-citizens, an animal 'which vaguely resembles an ambulatory pineapple'. It is a quarter of a millimetre long, and lives in the sand 500 metres deep in the world's oceans. Almost nothing is known about its life, and it has been named Nanaloricus mysticus.

John Fowles once suggested that the obsession with identifying and naming creatures was a corrupt symptom of the Western view of nature as property. Yet it can also be, as Wilson triumphantly argues, a mark of attentiveness, of respect. He has invented a word for this affectionate curiosity. He calls it biophilia: 'the innate affiliation of human beings with the natural world'.

(Photograph omitted)