After mankind has reshaped much of the biosphere’s landscapes, it is now able to document the geography of these changes with increasingly sophisticated data and tools. Geographic patterns of land-cover and -use are now quantified at very fine spatial resolutions, and models of future environmental change continue to improve in accuracy. In contrast, human knowledge of the geography of biodiversity at global scales, even in well-studied vertebrates, remains coarse. This constrains quantification of past and potential future human impacts on biodiversity and limits identification of pathways for sustainable management. Preliminary assessments across the whole terrestrial biosphere are now possible, but we need to be aware of the severe limitations presented by our coarse global-scale ecological knowledge and think of ways to overcome it.
I first review the current knowledge base of the geographic distribution of terrestrial vertebrates. I then present several studies that set out to use this data to draw first global-scale inferences about the potential impacts of anthropogenic change on biodiversity. These attempts include an assessment of past and future conservation risk across regions, quantifications of the correlates of past extinction risk, and investigations of the exposure of vertebrates as a whole and high-mountain specialists in particular to climate change. After making a case for the importance of a whole-biosphere perspective in environmental change research, I outline the constraints of a global approach. In particular, I explore the current grain-size limitation of global-scale ecology and the reduction of biological realism it causes. I document the ever-widening knowledge gap between our grasp of the anthropogenic change and our spatial knowledge of biodiversity. I attempt to formulate the specific challenge to ecologists and discuss potential avenues to meet it.