Questions of mass extinction

Earth's biodiversity is being overtaken by a mass extinction which, if allowed to proceed unchecked, could well eliminate between one quarter and one half of all species. Our conservation responses must be science-based if we are to address the problem in its full scope and with most productive use of conservation resources. Yet our scientific understanding of the impending mass extinction is inadequate in many salient respects. We have only a rudimentary grasp of the number of species at risk, of biodiversity depletion processes, of island biogeography in practice, and of evolutionary consequences, to cite but a few leading questions. The same applies to the issue of the most efficient strategies to confront the conservation challenge. Worse, there is scant evidence (due in part to gross lack of funding) of a comprehensive and coordinated campaign to mount a research effort of scope to match the problem. The paper broaches ten key questions that warrant urgent attention.