31 MARCH 2007, Page 44

Broadening the vision

Marcus Berkmann

THE EYE: A NATURAL HISTORY by Simon Ings Bloomsbury, £17.99, pp. 322, ISBN 9780747578055 ✆ £14.39 (plus £2.45 p&p) 0870 429 6655 ‘P opular science’: for some readers this remains a problematic cate gory. I’m sure proper scientists look askance at civilians reading such books on public transport, imagining their own abstruse specialities dumbed down for the hard-of-thinking. And the vast mass of arts graduates, who hate and fear science, remembering the bad trousers and unfortunate hairstyles of science undergraduates in their day, happily admit that they know nothing of the subject and understand even less. Some people I know have been boasting for nearly 20 years that they gave up A Brief History of Time before the end. It’s all too sad for words.

Stephen Hawking, though, has much to answer for. In his book, relatively straightforward ideas would be explained from first principles, while complex numbers, one of the most mind-blowing ideas in all mathematics, were swept aside in a single paragraph. Many of us had maths masters like this: so clever they could understand anything, except for the one thing they were paid to understand, which was that their pupils weren’t all as clever as they were. Other popular science titles, even awardwinning ones, have read like PhD theses, telling you everything interesting in an extended introduction, and then saying it all again, at greater length and more boringly, in the rest of the book. Then there are the science writers, usually American, who think they are wacky and zany and wish they’d been Douglas Adams, and long before you throw their books aside in disgust, you want them dead or, at least, very seriously harmed.

Recently, though, the genre has shown signs of growing up; certainly, better books are being published. Simon Ings’s book is one such. Ings is probably best known for his science-flecked novel The Weight of Numbers and also for not being the science writer Simon Singh (unless I have missed something and he is). In his acknowledgements Ings reveals that his agent had been looking for years for someone to write a popular, singlevolume work about the eye, and clearly after many lunches, he ground him down. But this is no dry textbook. In this ambitious work, Ings reaches into chemistry, evolutionary biology, anthropology, psychology, aesthetics and his own fertile imagination to produce an agglomeration of ideas and themes, aimed at neither the specialist nor the idiot, but somewhere tantalisingly in between. In many ways it’s the perfectly judged popular-science book: he assumes little or no prior knowledge, but he does take for granted an open mind and a certain curiosity. His book will bring out the intelligent 12-year-old in us all. You may even look on the world with new eyes.

Ings begins by defining his terms: vision belongs to a ‘commonwealth of the senses’. ‘It is not a unique and privileged sense, but an exquisite manifestation of a drive common to all living things — vegetable as well as animal — to harness light.’ He then traces the evolution of this commonwealth of the senses, discusses the oddities of our own human eyes, wonders whether thinking arises as a response to seeing, attempts to tackle one of the more intractable problems of vision understanding the retina — and then, as parts of your head are beginning to hurt, contemplates the future of vision. What does it mean to build an eye? When will we be able to say that a machine genuinely sees? It’s all put together with the lightest possible touch. Ings has some tricky ideas to put over, but illustrates them so deftly that you barely notice the spoonful of sugar as the medicine goes down. He also knows the value of the genuinely arresting piece of information. The ‘wow’ factor is consistently high.

Human beings, it transpires, have much better eyesight than we give ourselves credit for. We may lack ‘certain exotic adaptations that can aid nocturnal vision, [but] we can still detect light that is a billionth the strength of daylight.’ In good conditions this means we can see the flame of a single candle 17 miles away. Very few species can do better. (It’s our relatively poor hearing and sense of smell that let us down.) Eyes have developed and adapted in countless different and strange ways. Ings’s favourite is the surface-feeding fish anableps anableps, which lives in Central and South America and has four eyes, two for above the waterline, two for below. He gives lovely descriptions of the ways insects see: why bees fly straight into walls painted a single colour, and why wasps won’t sting you if you keep perfectly still. How long, I wondered, before Ings mentioned the giant squid? Only 23 pages, as it happens, although it turns out that that vast staring ghoulish eye is quite dissimilar to the human eye. Despite their superb visual acuity, kestrels find it hard to spot voles, their favourite food. But they can see the long trails of urine that voles leave and which reflect ultraviolet light. As Ings puts it, all they have to do is ‘follow the arrows’. Many readers will find themselves doing something similar as they rip happily through this richly enjoyable book.