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Updated: Jun 21, 2026
07:41
Modeling the Size Spectrum for Macroinvertebrates and Fishes in Stream Ecosystems
Published on: July 30, 2019
Generalized models reveal stabilizing factors in food webs
Thilo Gross1, Lars Rudolf, Simon A Levin
1Max Planck Institute for Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany. thilo.gross@physics.org
Science (New York, N.Y.)
|August 8, 2009
Summary
This study reveals that link strength variability stabilizes small food webs but destabilizes larger ones. Key findings include a new power law for food-web stability and two universal rules for enhancement.
Area of Science:
- Ecology
- Theoretical Ecology
- Network Theory
Background:
- Understanding food web stability is crucial for ecological research.
- Previous studies faced limitations due to simplifying assumptions or small sample sizes.
Purpose of the Study:
- To investigate the factors influencing food web stability using generalized modeling.
- To identify universal rules governing food web stability across varying scales.
Main Methods:
- Simulated billions of food web replicates with nonlinear interactions.
- Analyzed food webs with up to 50 species.
Main Results:
- Higher link strength variability stabilizes small food webs but destabilizes larger ones.
- A novel power law was identified for food-web stability scaling with species number and connectance.
- Two universal rules for enhanced stability were discovered: high-trophic-level species with diverse prey and intermediate-trophic-level species with diverse predators.
Conclusions:
- Food web stability is scale-dependent regarding link strength variability.
- The identified power law and universal rules offer new insights into ecological network structure and stability.
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