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Shape matters: the relationship between cell geometry and diversity in phytoplankton
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  • Alexei Ryabov,
  • Onur Kerimoglu,
  • Elena Litchman,
  • Irina Olenina,
  • Leonilde Roselli,
  • Alberto Basset,
  • Elena Stanca,
  • Bernd Blasius
Alexei Ryabov

Corresponding Author:[email protected]

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Onur Kerimoglu
Carl von Ossietzky University of Oldenburg
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Elena Litchman
Michigan State University
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Irina Olenina
Environmental Protection Agency
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Leonilde Roselli
Agency for the Environmental Prevention and Protection
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Alberto Basset
University of Salento
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Elena Stanca
University of Salento
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Bernd Blasius
University of Oldenburg
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Size and shape profoundly influence an organism’s ecophysiological performance and evolutionary fitness, suggesting a link between morphology and diversity. However, not much is known about how body shape is related to taxonomic richness, in particular in the microbial realm. Here we analyse global datasets of unicellular phytoplankton, a major photosynthetic group with an exceptional diversity of cell sizes and shapes. Using two measures of cell shape elongation, we quantify taxonomic diversity as a function of cell size and shape. We find that cells of intermediate volume have the greatest shape variation, from oblate to extremely elongated forms, while small and large cells are mostly compact (e.g., spherical or cubic). Taxonomic diversity is strongly related with cell elongation and cell volume, with both traits, in combination, explaining up to 92% of total variance. Diversity decays exponentially with cell elongation and displays a log-normal dependence on cell volume, peaking for compact, intermediate-volume cells. These previously unreported broad patterns in phytoplankton diversity reveal selective pressures and ecophysiological constraints on the geometry of phytoplankton cells which may improve our understanding of marine ecology and the evolutionary rules of life.
09 Oct 2020Submitted to Ecology Letters
12 Oct 2020Submission Checks Completed
12 Oct 2020Assigned to Editor
22 Oct 2020Reviewer(s) Assigned
24 Nov 2020Review(s) Completed, Editorial Evaluation Pending
26 Nov 2020Editorial Decision: Revise Major
14 Dec 20201st Revision Received
15 Dec 2020Submission Checks Completed
15 Dec 2020Assigned to Editor
15 Dec 2020Review(s) Completed, Editorial Evaluation Pending
15 Dec 2020Editorial Decision: Accept
Apr 2021Published in Ecology Letters volume 24 issue 4 on pages 847-861. 10.1111/ele.13680