System, Ecosystem, and Social System
The concept of system is also an excellent example of the capacity of human thought to perceive both parts and the way they function or interact. A closer reading of some of the concepts so frequently cited in ecological research using ecosystem concepts is desirable. There are three closely related ones that need distinguishing: Steady state, Equilibrium or stability and Homeostasis. Clearly human social systems are their own kind of system; or rather, to call human affairs "systems" is a heuristic or experimental exercise, and not an identification of substance. Human social systems are all adaptive: some are more dynamic than others. Human or cultural ecology is a study of how adaptive systems influence the physical environment and the human environment as well. Examples of complex socionatural systems are beginning to accumulate as ecologists and economists collaborate on particular problem-cases of environmental or social damage resulting from human use of resources.