They can be described, even predicted, with the right equation. Chaos scientist Stephen Guastello of Marquette University in Milwaukee applied predator-prey dynamics to the world fish catch. Predators, in this case, are fishing boats, and prey are fish. The relationship between populations of predators and prey can display chaotic cycles in which one rises, then the other falls. No two cycles are alike.
Nonlinear equations can have multiple solutions.
Another possible trend showed the catch falling indefinitely. Scientists are using other approaches to study dynamic change. Sometimes they treat the economy as a part of the ecosystem. Costanza was the principal designer of a computer model that projected long-term changes in a section of the Atchafalaya marsh. The model divided the area into a checkerboard of 2,479 squares, each a square kilometer.