ABSTRACT
As Scott et al. note, the choice of a conservation goal— what risk of extinction over what period of time—"may be guided by science but [is] essentially rooted in society's values." Nature's risk is something any farmer, hiker or beachgoer learns to endure. Variability in weather, for example, can affect these people and their chosen activities, and so has given rise to weather forecasting, cloud seeding, and bustling markets in raincoats and umbrellas. Variation in nature encourages to acquire better information reduce that variation and find ways to adapt to it. In an uncertain world, the castaways have additional opportunities for shirking by hiding behind nature's risk. Nature frequently produces surprises, such as new diseases, droughts, storms, floods and fire. The inherent dynamic complexity of natural biological systems precludes accurate, specific predictions in most situations; human activities greatly add to and compound this complexity.
