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Scale transition theory with special reference to species coexistence in a variable environment
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA. pchesson@u.arizona.edu
Journal of Biological Dynamics
|August 14, 2012
Summary
Scale transition theory mathematically models population dynamics across scales. It reveals how nonlinearities and variation create emergent properties and explains species coexistence through temporal fluctuations and nonlinear dynamics.
Area of Science:
- Ecology
- Mathematical Biology
- Population Dynamics
Background:
- Understanding how population dynamics change across spatial and temporal scales is crucial.
- Emergent properties on larger scales arise from interactions between nonlinearities and variation on smaller scales.
- Species coexistence mechanisms, like the storage effect, are often linked to temporal fluctuations.
Purpose of the Study:
- To present scale transition theory as a mathematical framework for analyzing population dynamics.
- To explain how nonlinear functions and variation interact to produce scale-dependent phenomena.
- To elucidate the mechanisms of species coexistence driven by temporal fluctuations.
Main Methods:
- Applying statistical theory for averaging nonlinear functions.
- Utilizing spatial models where larger-scale variables are averages of smaller-scale ones.
- Analyzing temporal averages of per capita growth rates to understand long-term population trends.
Main Results:
- Scale transition theory provides a method to understand emergent properties from small-scale interactions.
- The theory explains species coexistence through temporal fluctuations and nonlinear dynamics.
- Key coexistence mechanisms identified include the storage effect and nonlinear competitive variance.
Conclusions:
- Scale transition theory offers a robust mathematical approach to ecological scaling problems.
- Understanding the interplay between nonlinearity and variation is key to predicting population dynamics.
- The theory clarifies the role of temporal fluctuations in maintaining species diversity.
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