Figure 1.

Commonness and rarity of tree and shrub species in the 1982 census of the 50 ha forest plot on Barro Colorado Island, Panama. Cumulative number of individuals (y axis) over species ranked in abundance from common (left end, x axis) to rare (right end, x axis). Of the 306 species, the nine most abundant species make up half of the individuals (about 121,000 individuals). However, the rarest half (153) of the Barro Colorado Island species collectively constitute only six tenths of one percent of all individuals.