Ecological Systems are Not Dynamic Systems: Some Consequences of Individual Variability

Abstract

Ecological systems are not dynamic systems (they are not "state variable models"), because they consist of individuals, which are different. An individual-based model of single population of competing individuals is presented to explain this. The model illustrates the meaning of "density dependence" on the level of individuals. Two time scales on which density dependence is operating can be distinguished: "between generation" and "within- generation". For the latter one, individual variability is an important factor