Coexistence of competitors in metacommunities due to spatial variation in resource growth rates; does R* predict the outcome of competition?
Simple mathematical models are used to investigate the coexistence of two consumers using a single limiting resource that is distributed over distinct patches, and that has unequal growth rates in the different patches. Relatively low movement rates or high demographic rates of an inefficient resource exploiter allow it to coexist at a stable equilibrium with a more efficient species whose ratio of movement to demographic rates is lower. The range of conditions allowing coexistence depends on the between-patch heterogeneity in resource growth rates, but this range can be quite broad. The between-patch movement of the more efficient consumer turns patches with high resource growth rates into sources, while low-growth-rate patches effectively become sinks. A less efficient species can coexist with or even exclude the more efficient species from the global environment if it is better able to bias its spatial distribution towards the source patches. This can be accomplished with density independent dispersal if the less efficient species has a lower ratio of per capita between-patch movement rate to demographic rates. Conditions that maximize the range of efficiencies allowing coexistence of two species are: a relatively high level of heterogeneity in resource growth conditions; high dispersal (or low demographic rates) of the superior competitor; and low dispersal (or high demographic rates) of the inferior competitor. Global exclusion of the more efficient competitor requires that the inferior competitor have sufficient movement to also produce a source-sink environment.
Duke Scholars
Altmetric Attention Stats
Dimensions Citation Stats
Published In
DOI
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Ecology
- 4104 Environmental management
- 4102 Ecological applications
- 3103 Ecology
- 0603 Evolutionary Biology
- 0602 Ecology
- 0501 Ecological Applications
Citation
Published In
DOI
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Ecology
- 4104 Environmental management
- 4102 Ecological applications
- 3103 Ecology
- 0603 Evolutionary Biology
- 0602 Ecology
- 0501 Ecological Applications