Introduction: The Heterogeneity of Heterogeneity: A Glossary

Despite its ubiquitous relevance to most ecological and evolutionary processes, a comprehensive description of the structural and dynamic aspects of heterogeneity has never been constructed. Intuitively, the concept of heterogeneity is clear, but as we scrutinize it our initial impression fractures into complexity. The term appears rather simple when contrasted with homogeneity, the absence of variation. However, one can view heterogeneity from a variety of perspectives, some of which are well known and explored, but many of which are not. Some perspectives have important consequences for ecology and evolution, whereas others appear, at least initially, to be logical curiosities. Furthermore, different perspectives may be inclusive, exclusive, complementary, or overlapping, a problem that hints at the nature of the phenomenon itself.