Figure 1. Projected Range Transformations.

Frequency distribution of projected range transformations for 8,750 bird species by 2100 across the four MA socioeconomic scenarios (histograms, left axis). Within each bar, the height of the shading refers to proportion of projected transformation due to habitat conversion (dark gray) or climate change (light gray). The count of species with exactly zero range transformations is represented as open bars and separated by a gap from the bars representing >0 to ≤100% range transformation. Points with error bars give the average (± SE) current geographic range size (in km²) for species in each range transformation category. Although none of the scenarios is likely to predict the actual pattern of land-cover change, they provide “broad confidence limits” that are likely to span the range of possible futures. The four scenarios are briefly described in Materials and Methods.