Historical View of the Concept of Ecosystem Convergence

Abstract

Plants (or animals) living in separate but climatically similar areas often resemble each other to some extent. Sometimes this is explained by common ancestry; where organisms have only remote ancestral connections, however, their similarities are more often attributed to the effects of similar environmental conditions on the evolution of each group. Traditionally, similarity through common descent, homology, has been called parallel evolution; similarity based on analogous structures is referred to as convergent evolution. Because it is often difficult to distinguish between the two, in practice the term convergence refers loosely to those cases where no obvious close relationship exists between the organisms showing convergent characteristics.