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Linking rates of diffusion and consumption in relation to resources
Tal Avgar1, Daniel Kuefler, John M Fryxell
1Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada. tavgar@uoguelph.ca
The American Naturalist
|July 14, 2011
Summary
Ecological models linking consumer intake (functional response) and animal movement (random walk) were synthesized. Resource aggregation can increase consumer movement but decrease consumption, offering a new explanation for movement patterns.
Area of Science:
- Ecology
- Theoretical Ecology
- Mathematical Biology
Background:
- The functional response models consumer intake rate versus resource abundance.
- The random walk model describes animal movement, often approximated by diffusion.
- These fundamental ecological models are rarely integrated in theory.
Purpose of the Study:
- To synthesize functional response and random walk models.
- To link consumer movement and resource interaction dynamics.
- To explore how resource attributes influence consumer behavior.
Main Methods:
- Developed a synthetic model based on shared logical premises.
- Analyzed how diffusion and consumption rates depend on resource abundance, aggregation, speed, and consumer handling time/persistence.
- Investigated the statistical mechanics of movement.
Main Results:
- Consumer diffusion rates increase with resource aggregation.
- Mobile resources can lead to reduced consumer consumption rates.
- Resource-dependent movement patterns may arise from statistical mechanics, not just area-restricted search.
Conclusions:
- A unified model linking functional response and random walk is derived.
- Resource characteristics significantly impact consumer movement and feeding.
- This synthesis offers a mechanistic alternative to adaptive explanations for movement patterns.
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