'Anthropological arse' in saddle

Newmarket is only 90 miles from London, and it is often on television. But it is a million miles from our normal life. Newmarket is focused on another species. Wealth, or disaster, is a result of understanding the horse. But, according to Rebecca Cassidy, believing that you understand horses may be absurd. There is little logic to horse performance.

Newmarket therefore has to cloak itself in rituals, language and hierarchy that has the effect of hiding the key fact (horse performance cannot be predicted) from outsiders. More important, the insiders hide this fact from themselves.

This is one of the main themes that emerges from Cassidy's work. As a horse-loving anthropology PhD student, Cassidy spent 15 months as a participant observer in Newmarket.

Newmarket must not - cannot - accept that horse performance is so random that horse skills may be based on nothing. If a horse has an unexpected win, this event must be made logical. If you go back into the horse's genealogy, you can see signs that were there all along. With hindsight, the forebears are re-examined to support a new view. And the same logic is used to explain trainer performance. It is their ancestors who make them successful, or their lack of horseracing ancestry if they fail.

Another method of applying logic to near-random events is the special language of horse people. If you as an outsider believe these words to be meaningless, then you have missed the point. You fail to interpret signs that are obvious.

Nature is selectively viewed. Female horses are seen as less important than the males. It must follow, according to Newmarket opinion, that the downplaying of human females is merely a reflection of nature. Being against the Newmarket hierarchy is to argue against the facts of nature, that is pointless. Moreover, you are born a horse person or not. Newmarket has a training school for lads and lasses. But Newmarket really believes that a true horse person is born with the skills.

Cassidy is a careful analyst of minor social behaviour. (One small theme is the correct style in the face of terrifying horse dangers: be nonchalant.) For someone starting ethnography, this book is ideal. But if only her language were more welcoming to the wider world, Cassidy would be sitting on a research goldmine. For example, the relationships between humans and animals could not be more relevant, politically. And, Newmarket is frighteningly similar to the City of London - both have inner groups whose language leads to the befuddlement of punters who can never quite make sense of their losses.

This is an exhilarating book. You feel affection and empathy for Newmarket people. As an outsider, you know that you will always be an alien there.

But you do now sympathise with those who exclude you.

Above all, the reader feels affection towards the author. Her presence is felt but never fully seen. She rides in the middle distance, on the other side of a thick hedge of anthropological jargon. She has taken real physical risks to report back for our benefit. We watch over her, sleeping in the back of a smelly horse box, returning from a race. We see her at a new yard. To test her, she is given a wild horse, to take out with the "first lot", at dawn on the heath. A trainer refers to her "anthropological arse", and the phrase exemplifies the whole book - it is both academic and animal, with the author putting herself on the line. Despite the jargon, we can smell the fresh air.

Jeremy Baker is lecturer in marketing, London Metropolitan University. He was recently part of a research team studying racehorse owners.