Geoscience Reference
In-Depth Information
“use value” in the technical literature. A market value is the price that
a good commands in the store or on the Internet. A near-market value
is the market price of something that is obtained outside the market, as
in the price of the home repair job. It has been tempting for scientists
concerned about ecosystem and species losses to point to the use, mar-
ket, or near-market damages that might occur with species loss. One
argument is that the potential losses are large because a substantial frac-
tion of Western pharmaceuticals are derived from rain forest ingredi-
a fern species disappears, we are foregoing the miracle cure to AIDS
that lurks hidden in the Brazilian forest.
The reality is more complicated. A recent review of new drug enti-
ties found that natural products are indeed important for developing
new drugs. For example, almost half of the new cancer drugs developed
over the last six decades were either natural products or directly derived
from natural products. The natural source varies greatly, however, from
ones discovered in laboratories to ancient Chinese herbal remedies.
Only one new drug in the last three decades came from the rain forest
(Taxol), and it was from a temperate rather than a tropical rain forest.
Many drugs have natural products as ancestors if we follow their family
tree back far enough, but they have since been optimized in the labora-
tory, and they have often been synthesized once their natural product
structures were analyzed.
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On the whole, having worked with a team of students for a summer
studying this question, I found it impossible to evaluate the hypothesis
that signifi cant medicinal riches will be lost in the disappearing rain
forests of the world. There is simply no compelling evidence on either
side. However, we can make one point with confi dence: Most of the eco-
nomic value of threatened species and ecosystems will not be found in
the marketplace. Perhaps preserving species is important, but the value
of the preservation will not be found on the stock market. Ecosystems
and species simply do not have much cash-and-carry value in today's
market economies.
Where then does their value come from? It comes from the external-
ity or “nonuse” values. While we usually think of externalities as nega-
