Figure 4 . Density histograms of species’ standardized niche
breadth for temperature and precipitation among (a ) all seed
plants in our dataset; (b ) only lowland species; (c ) only
montane species; (d ) only alpine species. Warmer (cooler) colors
indicate greater (fewer) species with that combination of niche
parameters. Univariate histograms for niche breadth variables are given
along the margins of each plot.