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Community trait overdispersion due to trophic interactions: concerns for assembly process inference.

ABSTRACT: The expected link between competitive exclusion and community trait overdispersion has been used to infer competition in local communities, and trait clustering has been interpreted as habitat filtering. Such community assembly process inference has received criticism for ignoring trophic interactions, as competition and trophic interactions might create similar trait patterns. While other theoretical studies have generally demonstrated the importance of predation for coexistence, ours provides the first quantitative demonstration of such effects on assembly process inference, using a trait-based ecological model to simulate the assembly of a competitive primary consumer community with and without the influence of trophic interactions. We quantified and contrasted trait dispersion/clustering of the competitive communities with the absence and presence of secondary consumers. Trophic interactions most often decreased trait clustering (i.e. increased dispersion) in the competitive communities due to evenly distributed invasions of secondary consumers and subsequent competitor extinctions over trait space. Furthermore, effects of trophic interactions were somewhat dependent on model parameters and clustering metric. These effects create considerable problems for process inference from trait distributions; one potential solution is to use more process-based and inclusive models in inference.

SUBMITTER: Pontarp M

PROVIDER: S-EPMC5069517 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Community trait overdispersion due to trophic interactions: concerns for assembly process inference.

Pontarp Mikael M Petchey Owen L OL

Proceedings. Biological sciences 20161001 1840

The expected link between competitive exclusion and community trait overdispersion has been used to infer competition in local communities, and trait clustering has been interpreted as habitat filtering. Such community assembly process inference has received criticism for ignoring trophic interactions, as competition and trophic interactions might create similar trait patterns. While other theoretical studies have generally demonstrated the importance of predation for coexistence, ours provides ...[more]

PMID: 27733548

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Dataset Information

Community trait overdispersion due to trophic interactions: concerns for assembly process inference.

Publications

Community trait overdispersion due to trophic interactions: concerns for assembly process inference.

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