Sir

Your recent News Feature “Bioprospects less than golden” (Nature 429, 598–600; 2004) is the latest to document the disappointments of bioprospecting. It suggests that “new rules on ownership” might give bioprospecting a boost. Our experience leads us to doubt this conjecture. The reason commercial interests are not willing to pay much for biodiversity is that it is not worth much to them. This may seem paradoxical, given that new products can be worth billions of dollars, but our conclusion emerges from several basic principles of economics.

First, the spectacular earnings available from infrequent research successes must cover the far more common failures. Second, even in bioprospecting, costs are dominated by specialized labour and equipment rather than the chemical entities from which products are crafted. Finally, and most importantly, untested natural chemical entities are not scarce, and for that reason, they should not be expensive. A pharmaceutical researcher's willingness to pay for a natural product lead is determined by the probability that the lead will result in a useful new product multiplied by the probability that the same product would not be developed from any of the other leads available to the researcher. When there are large numbers of potential leads, successes must either be so unlikely as to make searching unattractive or so probable as to render competing leads redundant. Either way, researchers will not pay much for any particular untested product.

Your News Feature emphasizes that rules must be agreed for the allocation of genetic resources, and this is certainly important. Yet the biggest practical problem with bioprospecting may be unrealistic expectations. Our sense is that governments and advocates in developing countries have often been misled about the value of their biological wealth. Consequently, they hold out for spectacular gains that they are unlikely to achieve, and all too often forego the more modest but more readily achievable benefits such as those that your News Feature describes as arising from Phyllis Coley's programme in Panama.