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Turbulent dispersal promotes species coexistence.

ABSTRACT: Several recent advances in coexistence theory emphasize the importance of space and dispersal, but focus on average dispersal rates and require spatial heterogeneity, spatio-temporal variability or dispersal-competition tradeoffs to allow coexistence. We analyse a model with stochastic juvenile dispersal (driven by turbulent flow in the coastal ocean) and show that a low-productivity species can coexist with a high-productivity species by having dispersal patterns sufficiently uncorrelated from those of its competitor, even though, on average, dispersal statistics are identical and subsequent demography and competition is spatially homogeneous. This produces a spatial storage effect, with an ephemeral partitioning of a 'spatial niche', and is the first demonstration of a physical mechanism for a pure spatiotemporal environmental response. 'Turbulent coexistence' is widely applicable to marine species with pelagic larval dispersal and relatively sessile adult life stages (and perhaps some wind-dispersed species) and complements other spatial and temporal storage effects previously documented for such species.

SUBMITTER: Berkley HA

PROVIDER: S-EPMC2847191 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Turbulent dispersal promotes species coexistence.

Berkley Heather A HA Kendall Bruce E BE Mitarai Satoshi S Siegel David A DA

Ecology letters 20100301 3

Several recent advances in coexistence theory emphasize the importance of space and dispersal, but focus on average dispersal rates and require spatial heterogeneity, spatio-temporal variability or dispersal-competition tradeoffs to allow coexistence. We analyse a model with stochastic juvenile dispersal (driven by turbulent flow in the coastal ocean) and show that a low-productivity species can coexist with a high-productivity species by having dispersal patterns sufficiently uncorrelated from ...[more]

PMID: 20455921

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Turbulent dispersal promotes species coexistence.

Publications

Turbulent dispersal promotes species coexistence.

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