FIGURE 2.

Comparison of ethnomedicinal selection and pharmacological research effort. The left “column” (dark gray) shows the decreasing numbers of potential leads, if focus is on taxa (middle row) or lineages (bottom row) with ethnomedicinal use. This column shows that a focus on ethnomedicinal hotnode clades reduces the size of the species pool from 2837 species in total to 126 species that have ethnomedicinal use and are inside a hotnode clade. The arrows show the proportions of total flora represented in the samples, for example, the 126 species with ethnomedicinal use in the bottom row represent 4% of all species. This is 4% of all species. The right “column” (light gray) shows the proportion of these taxa that have been screened according to our survey. If focus is on the whole flora, there are 98 genera that have been investigated pharmacologically (43% of all genera). Considering the ethnomedicinally important lineages (bottom row), there are 34 genera with ethnomedicinal use and have been characterized pharmacologically that belong to hotnode clades (92% of the genera with ethnomedicinal use and in hot modes). The circled numbers in blue show the number of species that have yielded drugs approved for use or clinical trial by the FDA. As focus on ethnomedicinally important groups increases, there is a concomitant increase in research effort, but fewer drugs approved for use or clinical trial by the FDA.