Figure 1. Conservation Efforts Hinge on Understanding the Factors Controlling Biodiversity.

(A) The diverse forest canopy on Barro Colorado Island, Panama, has provided ecologist Stephen Hubbell with years of data to test his controversial neutral theory of biodiversity and biogeography.

(B) Despite the different fruit types and dispersal modes pictured here, Hubbell wonders how well patterns of diversity can be explained by focusing on the similarity of species rather than their differences. Photos courtesy of Christian Ziegler.