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Published on: March 12, 2013
A robust measure of food web intervality
Daniel B Stouffer1, Juan Camacho, Luís A Nunes Amaral
1Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA.
Summary
Food web intervality, a measure of prey contiguity, is robustly quantified. Empirical food webs show a strong bias toward intervality, supporting single-dimensional niche mapping and ecosystem modeling.
Area of Science:
- Ecology
- Theoretical Ecology
- Food Web Dynamics
Background:
- Food web intervality quantifies the trophic structure of ecological communities.
- Previous studies suggested empirical food webs deviate from strict intervality.
- Understanding niche dimensionality is crucial for ecosystem modeling.
Purpose of the Study:
- To introduce a mathematically robust measure for food web intervality.
- To test the hypothesis that empirical food webs exhibit intervality.
- To validate assumptions for static and dynamic ecosystem models.
Main Methods:
- Development of a novel mathematical measure for quantifying food web intervality.
- Comparison of empirical food web data against relevant null hypotheses.
- Statistical analysis to assess the degree of prey contiguity.
Main Results:
- Empirical food webs demonstrate a significant bias toward intervality (prey contiguity).
- A robust measure for food web intervality was successfully introduced.
- Species diets in empirical food webs can be effectively mapped onto a single dimension.
Conclusions:
- Empirical food webs are strongly biased towards intervality.
- The findings validate a key assumption of the static niche model.
- Results provide essential guidance for developing dynamic ecosystem models.
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