Diversity is maintained by seasonal variation in species abundance.
Ontology highlight
ABSTRACT: Background
Some of the most marked temporal fluctuations in species abundances are linked to seasons. In theory, multispecies assemblages can persist if species use shared resources at different times, thereby minimizing interspecific competition. However, there is scant empirical evidence supporting these predictions and, to the best of our knowledge, seasonal variation has never been explored in the context of fluctuation-mediated coexistence.Results
Using an exceptionally well-documented estuarine fish assemblage, sampled monthly for over 30 years, we show that temporal shifts in species abundances underpin species coexistence. Species fall into distinct seasonal groups, within which spatial resource use is more heterogeneous than would be expected by chance at those times when competition for food is most intense. We also detect seasonal variation in the richness and evenness of the community, again linked to shifts in resource availability.Conclusions
These results reveal that spatiotemporal shifts in community composition minimize competitive interactions and help stabilize total abundance.
SUBMITTER: Shimadzu H
PROVIDER: S-EPMC3856667 | biostudies-literature | 2013 Sep
REPOSITORIES: biostudies-literature
Publications
Diversity is maintained by seasonal variation in species abundance.
Shimadzu Hideyasu H Dornelas Maria M Henderson Peter A PA Magurran Anne E AE
BMC biology 20130904
<h4>Background</h4>Some of the most marked temporal fluctuations in species abundances are linked to seasons. In theory, multispecies assemblages can persist if species use shared resources at different times, thereby minimizing interspecific competition. However, there is scant empirical evidence supporting these predictions and, to the best of our knowledge, seasonal variation has never been explored in the context of fluctuation-mediated coexistence.<h4>Results</h4>Using an exceptionally well ...[more]
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