Caroline Fraser’s book Rewilding the World is a call to retrofit more than a century of nature conservation in the United States and around the world. Why, at this late date, is it so important that we redesign the global conservation system? Conservationists are rightly proud of their collective accomplishment in bringing some 12 percent of the earth’s land under protection so that future generations may know and enjoy nature. Why should this success now be in question?
The answer lies in the fact that our zeal for conserving nature far outran the science of how to do it. The modern conservation movement dates to the founding of the World Wildlife Fund in Europe and the Nature Conservancy in the United States after World War II. Both organizations hired scientists to advise them, but the scientists found themselves having to invent programs and priorities out of thin air. Conservation did not have a solid scientific basis until a conference in San Diego in September 1977. Before that, scattered articles presented results of studies that could, by inference or extension, suggest conservation strategies, but as often happens in science, controversy erupted over the interpretation of the results, and when scientists disagree among themselves, everyone else stops listening. The San Diego conference was brilliantly conceived to bring the scientific community together in a consensus that would move the field forward.
Conservation biology had failed to develop earlier because it confronted a methodological impasse: the difficulty of studying the process of extinction of species. Indeed, one definition of conservation biology is that it is the science of why extinctions occur and how to prevent them. Until the 1970s, nearly all scientists who studied extinction were paleontologists who studied fossils. Extinctions are abundantly registered in the fossil record, but the great majority of ancient organisms appeared and disappeared without apparent cause. Exceptions occurred in rare global mass extinctions, of which there have been only five since the origin of multicellular life, one of which was the meteorite impact that ended the age of dinosaurs.
Between mass extinctions, which have occurred at intervals of roughly 100 million years, there were countless extinctions of individual species taking place in the “background.” But the rate was so slow, approximately one in a million species per year, that it didn’t appear relevant to a world in which native habitats were disappearing at an alarming rate and countless animals and plants were being exploited for commercial purposes. If humans were going to “manage” nature so as to prevent extinctions, an entirely new branch of science was needed to address the problem.
The need to retrofit the current conservation system arises out of science that developed during the latter half of the twentieth century. Fraser provides an introduction to this science as the rationale behind her call for “rewilding the world.” What, exactly, she means by …