A NEW breed of gold-diggers are on the prowl. In the search for plant species yielding new medicines and better crops, rich and relatively unexplored ecosystems are now resounding to the tramp of the biodiversity prospector. But, like the stampede at John Sutter's mill, this "gene rush" could turn ecosystems and local communities inside out.

Done right, however, biodiversity exploration for commercially valuable genetic and biochemical resources can bolster both economic and conservation goals, while underpinning medicinal and agricultural advances. What "doing right" means, in this context, is the central question of the book under review.

The value of Biodiversity Prospecting lies in the personal experience of its authors. Many of them were instrumental to a landmark agreement between Merck & Co (of New Jersey, USA) and the Instituto National de Biodiversidad (INBio) at Costa Rica, encouraging natural resource exploration while promoting conservation. The agreement also sought to ensure that bioprospecting be legally undertaken with the consent of the communities involved.

The book covers many aspects of the Merck-INBio agreement while placing it in a larger perspective. The normative question of whether countries should commercialise genetic and biochemical resources remains untouched. But the fact that commercialisation ought to support conservation and development is very much the argument. Appropriate policies and institutions are required to inject this positive ethic into the marketplace. The value of biodiversity as grist to the pharmaceutical mill is, after all, only a portion of its value to society.

It is important to understand how the market and species diversity are related. In Kenya, the entire adult population of Maytenus buchananni -- a source of the anti-cancer compound maytansine -- was harvested by a mission sponsored by the US National Cancer Institute, collecting 27,215 kg for testing in its drug development programme. Genetic and biochemical resources being "non-rival public goods", market forces tend to enhance "the tragedy of the commons".

Perhaps to exemplify that such tragedies needn't be legion, the Costa Rican government established INBio to facilitate conservation and the sustainable use of biodiversity. The agreement with Merck shows how pharmaceutical development and conservation can co-exist -- but, as the authors rightly emphasise, this agreement should be treated as an exploratory one. Merck paid INBio over $ 1 million to help INBio expand its training programme and its extraction laboratory, which, the authors suggest, implies that such agreements need not be a zero sum game.

In the relatively new field of biodiversity prospecting, this book is an useful one. A model contract in the appendix may interest future parties and an extensive bibliography facilitates inquiries further afield. The book should appeal to a wide range of readers.

Bhanusingha Ghosh is a research scholar at Jawaharlal Nehru University, New Delhi