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Modeling the Size Spectrum for Macroinvertebrates and Fishes in Stream Ecosystems
Published on: July 30, 2019
Consumer-resource body-size relationships in natural food webs
Ulrich Brose1, Tomas Jonsson, Eric L Berlow
1Department of Biology, Darmstadt University of Technology, Darmstadt, Germany. brose@bio.tu-darmstadt.de
Ecology
|November 9, 2006
Summary
Consumer-resource body size ratios vary significantly across ecosystems. Aquatic herbivores and detritivores have much larger body size ratios than carnivorous predators, impacting food web dynamics.
Area of Science:
- Ecology
- Food web dynamics
- Biogeography
Background:
- Differences in consumer-resource body size influence ecological interactions and food web structure.
- The global distribution and systematic variation of these body-size ratios across habitats and taxa remain poorly understood.
Purpose of the Study:
- To investigate the general distribution of consumer-resource body-size ratios globally.
- To determine if these ratios vary systematically among different habitats and taxonomic groups.
Main Methods:
- Utilized a unique global database of consumer and resource body sizes.
- Analyzed body-size ratios for various consumer types (herbivores, detritivores, predators) and habitats.
Main Results:
- Aquatic herbivorous and detritivorous consumers exhibit body-size ratios orders of magnitude larger than carnivorous predators.
- Predator-prey body-size ratios differ significantly across habitats (freshwater > marine/terrestrial) and predator/prey types (vertebrate predators > invertebrate predators; invertebrate prey > ectotherm vertebrate prey).
Conclusions:
- Consumer-resource body-size ratios are not uniform and vary systematically across habitats and consumer/prey types.
- These findings suggest that consumer-resource interaction strengths may differ systematically across ecosystems and consumer groups, with implications for food web functioning.
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