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A new dynamic null model for phylogenetic community structure.

ABSTRACT: Phylogenies are increasingly applied to identify the mechanisms structuring ecological communities but progress has been hindered by a reliance on statistical null models that ignore the historical process of community assembly. Here, we address this, and develop a dynamic null model of assembly by allopatric speciation, colonisation and local extinction. Incorporating these processes fundamentally alters the structure of communities expected due to chance, with speciation leading to phylogenetic overdispersion compared to a classical statistical null model assuming equal probabilities of community membership. Applying this method to bird and primate communities in South America we show that patterns of phylogenetic overdispersion - often attributed to negative biotic interactions - are instead consistent with a species neutral model of allopatric speciation, colonisation and local extinction. Our findings provide a new null expectation for phylogenetic community patterns and highlight the importance of explicitly accounting for the dynamic history of assembly when testing the mechanisms governing community structure.

SUBMITTER: Pigot AL

PROVIDER: S-EPMC4674968 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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A new dynamic null model for phylogenetic community structure.

Pigot Alex L AL Etienne Rampal S RS

Ecology letters 20150106 2

Phylogenies are increasingly applied to identify the mechanisms structuring ecological communities but progress has been hindered by a reliance on statistical null models that ignore the historical process of community assembly. Here, we address this, and develop a dynamic null model of assembly by allopatric speciation, colonisation and local extinction. Incorporating these processes fundamentally alters the structure of communities expected due to chance, with speciation leading to phylogeneti ...[more]

PMID: 25560516

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Dataset Information

A new dynamic null model for phylogenetic community structure.

Publications

A new dynamic null model for phylogenetic community structure.

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