Organization of Ecosystems

The relevance of the hierarchy concept in biology has been questioned, but it is nevertheless a useful way to organize our perception of nature. The hierarchical ordering of nature is both structural and dynamic/ with the vertical separation of levels dependent on behavioral frequencies and the horizonal separation the result of the degree of interaction between systems. Within this hierarchy of natural systems, one can perceive both upward and downward causation. This perception provides a philosophical midground between holism and reductionism. At the ecological levels of organization, ecosystems are comprised of interacting organisms. Communities and populations are not natural systems and can best be recognized as subunits of ecosystems. Advances in ecosystem ecology must proceed from an understanding of ecosystem level behaviors and laws.