An Evolutionary Analysis of Insular and Continental Species

Abstract

Discussions of evolutionary problems usually fail to take into account the varying constitution and behavior of species among different groups of plants and animals. The species problem becomes a number of problems if there are a number of different entities that pass as species. Quite aside from confusions introduced by differing concepts and definitions of the basic taxonomic unit, the qualities of inter-breeding populations among such diverse things as, for instance, strong-flying birds, parasitic insects, world-circling primates, microscopic fungi, bacteria, slow-fruiting angiosperms, and crustacea of the ocean plankton are so various that no single, simple explanation, or any theoretic ideal, can account for the evolution of all of them.