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Backbones of evolutionary history test biodiversity theory for microbes.

ABSTRACT: Identifying the ecological and evolutionary mechanisms that determine biological diversity is a central question in ecology. In microbial ecology, phylogenetic diversity is an increasingly common and relevant means of quantifying community diversity, particularly given the challenges in defining unambiguous species units from environmental sequence data. We explore patterns of phylogenetic diversity across multiple bacterial communities drawn from different habitats and compare these data to evolutionary trees generated using theoretical models of biodiversity. We have two central findings. First, although on finer scales the empirical trees are highly idiosyncratic, on coarse scales the backbone of these trees is simple and robust, consistent across habitats, and displays bursts of diversification dotted throughout. Second, we find that these data demonstrate a clear departure from the predictions of standard neutral theories of biodiversity and that an alternative family of generalized models provides a qualitatively better description. Together, these results lay the groundwork for a theoretical framework to connect ecological mechanisms to observed phylogenetic patterns in microbial communities.

SUBMITTER: O'Dwyer JP

PROVIDER: S-EPMC4500224 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Backbones of evolutionary history test biodiversity theory for microbes.

O'Dwyer James P JP Kembel Steven W SW Sharpton Thomas J TJ

Proceedings of the National Academy of Sciences of the United States of America 20150623 27

Identifying the ecological and evolutionary mechanisms that determine biological diversity is a central question in ecology. In microbial ecology, phylogenetic diversity is an increasingly common and relevant means of quantifying community diversity, particularly given the challenges in defining unambiguous species units from environmental sequence data. We explore patterns of phylogenetic diversity across multiple bacterial communities drawn from different habitats and compare these data to evo ...[more]

PMID: 26106159

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Backbones of evolutionary history test biodiversity theory for microbes.

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Backbones of evolutionary history test biodiversity theory for microbes.

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