ABSTRACT
Protecting the world's biodiversity requires answers to a few not entirely rhetorical questions: Assuming agreement of the need to protect Earth's biological wealth, how much would you be prepared to pay to protect an endangered fly? Would you spend $1.50, $15, $150,000, or more? How about society as a whole, how much should society spend on the protection of this fly? Does the answer depend on the nature of the fly itself? On its role in the ecosystem? Or is the calculus based on something else—perhaps on what you must give up to save the fly, or your standard of living, or your priorities?
