The current and future role of transients in ecological theory

Background/Question/Methods

Much of ecological theory has traditionally focused primarily on the long term behavior of simple models as the way to understand ecological systems. Recently, however, there has been an increasing emphasis on understanding dynamics of ecological systems and corresponding models using a focus on transient behavior. Much of this recent interest has been on long transient behavior, defined as dynamics that are different from long term (asymptotic) behavior, but persist long enough to appear to be long term behavior. Ideas based on dynamical systems can shed light on much of this kind of dynamic behavior. Like many ideas in ecology, there are also earlier ideas and alternate approaches that can help scientists to make further progress. More recently there have been investigations of transient dynamics when the effects of stochasticity are included. One potentially intriguing approach is based on stochastic systems with absorbing states, with a focus on behavior before the system reaches the absorbing state.

Results/Conclusions

The biggest challenges for developing a deeper understanding of transient dynamics in ecology include relating any theoretical aspects to data and providing estimates for the expected time that a system will remain in a transient state. In parallel, in an applied context, it can be important to provide insights into how either to maintain a system in a transient state or to push a system off a transient. We will first illustrate ways of meeting these challenges in one of the simplest contexts possible that includes stochasticity, using the simplest system with absorbing states, namely a discrete time Markov chain. We will then describe how to extend these ideas using more complicated versions of stochastic systems with absorbing states and provide ecological examples of applications of this theory and future challenges.