Sir

In their peevish review of Bjørn Lomborg's book The Skeptical Environmentalist (Nature 414, 149–50; 2001), Stuart Pimm and Jeff Harvey miss the main point just as they have in their comments in the same review on Julian Simon's 1996 book The Ultimate Resource. The main target of both books is the politicization of ecology that has created a dogmatic environmentalism.

In their rush to rubbish Lomborg's book, the reviewers perhaps missed the significance of Lomborg's title. What Lomborg, and Simon before him, describe is the continued disparity between apocalyptic claims for the future of mankind, with figures issued from large organizations such as the United Nations Food and Agriculture Organization, which often or even usually show the opposite.

Pimm and Harvey state that there are ecological laws that ensure the correctness of doom-laden predictions. Presumably one of these laws enabled the environmentalist Paul Ehrlich to state in his 1968 book The Population Bomb: “The battle to feed all of humanity is over. In the 1970s and 80s, hundreds of millions of people will starve to death.”

Laws do not exist in biology, only generalizations; there are exceptions to every biological principle. Extrapolating from the past to predict a doom-and-gloom future has been an industry from Malthus onwards. But the ultimate resource is the creativity and skill of the human intellect; formulating the problem often generates solutions.

Democracy needs some people to shout loudly about the problems of the world in which we live, but such claims must be treated critically. That is Lomborg's thesis. Pimm and Harvey tell us that the main extinction threat is to species nothing is known about, which suggests these claims are hand-waving exercises. If nothing is known, how can extinction — or even teetering on the brink — be predicted?

If wilderness and species are to be saved from extinction, farming should be as efficient as possible. Excess agricultural land can then be returned to its original condition. Conservation is important, of course, but Pimm and Harvey's review suggests a common confusion with preservation. Human survival is the priority. Like all species in large numbers, our presence drives others to extinction. But new species will evolve to take advantage of the new environments created.

Open democratic debate about conservation policy is essential because there are many calls on public resources. The policies that are decided have to be the best return for money, and the public should vote on the outcome. In listing with glee the industry that will attempt to rubbish, instead of debate, Lomborg's book, Pimm and Harvey may have shot themselves in their feet. Such vehemence invites the conclusion that Lomborg (and Simon) have indeed exposed basic flaws in green political dogma.