The science of ecology has had a popular impact unlike that of any other academic field of research. Consider the extraordinary ubiquity of the word itself: it has appeared in the most everyday places and the most astonishing, on day-glo T-shirts, in corporate advertising, and on bridge abutments. It has changed the language of politics and philosophy— springing up in a number of countries are political groups that are self-identified as “Ecology Parties.” Yet who ever proposed forming a political party named after comparative linguistics or advanced paleontology? On several continents we have a philosophical movement termed “Deep Ecology,” but nowhere has anyone announced a movement for “Deep Entomology” or “Deep Polish Literature.” Why has this funny little word, ecology, coined by an obscure nineteenth-century German scientist, acquired so powerful a cultural resonance, so widespread a following? Behind the persistent enthusiasm for ecology, I believe, lies the hope that this science can offer a great deal more than a pile of data. It is supposed to offer a pathway to a kind of moral enlightenment that we can call, for the purposes of simplicity, “conservation.” The expectation did not originate with the public but first appeared among eminent scientists within the field. For instance, in his 1935 book Deserts on the March, the noted University of Oklahoma, and later Yale, botanist Paul Sears urged Americans to take ecology seriously, promoting it in their universities and making it part of their governing process. “In Great Britain,” he pointed out, . . . the ecologists are being consulted at every step in planning the proper utilization of those parts of the Empire not yet settled, thus . . . ending the era of haphazard exploitation. There are hopeful, but all too few signs that our own national government realizes the part which ecology must play in a permanent program. Sears recommended that the United States hire a few thousand ecologists at the county level to advise citizens on questions of land use and thereby bring an end to environmental degradation; such a brigade, he thought, would put the whole nation on a biologically and economically sustainable basis.