Many scholars have mapped Hardin's ideas onto a range of human–environment systems and have predicted dire consequences for their long-term viability unless his first solution, government ownership, is imposed. Even though >100,000 areas around the world are formally protected, and the effectiveness of many of these areas is unknown, some advocates still call for further efforts to create protected areas as the only way to protect biodiversity (11, 12). Others argue that "the only way to avoid the tragedy of the commons in natural resources and wildlife is ... by creating a system of private property rights" (ref. 13, p. 467). Marketable permits continue to be presented as the optimal method for solving free-rider problems and for providing effective common-pool resource management (14–16).** Furthermore, collaborative approaches involving community participation are frequently "portrayed as a cure-all," to the distress of researchers who work in the field (ref. 26, p. 382).