Rapid diversification associated with a macroevolutionary pulse of developmental plasticity

  1. Vladislav Susoy
  2. Erik J Ragsdale
  3. Natsumi Kanzaki
  4. Ralf J Sommer  Is a corresponding author
  1. Max Planck Institute for Developmental Biology, Germany
  2. Forestry and Forest Products Research Institute, Japan

Abstract

Developmental plasticity has been proposed to facilitate phenotypic diversification in plants and animals, but the macroevolutionary potential of plastic traits remains to be objectively tested. We studied the evolution of feeding structures in a group of 90 nematodes, including Caenorhabditis elegans, some species of which have evolved a mouthpart polyphenism, moveable teeth, and predatory feeding. Comparative analyses of shape and form, using geometric morphometrics, and of structural complexity revealed a rapid process of diversification associated with developmental plasticity. First, dimorphism was associated with a sharp increase in complexity and elevated evolutionary rates, represented by a radiation of feeding-forms with structural novelties. Second, the subsequent assimilation of a single phenotype coincided with a decrease in mouthpart complexity but an even stronger increase in evolutionary rates. Our results suggest that a macroevolutionary 'pulse' of plasticity promotes novelties and, even after the secondary fixation of phenotypes, permits sustained rapid exploration of morphospace.

Article and author information

Author details

  1. Vladislav Susoy

    Department for Evolutionary Biology, Max Planck Institute for Developmental Biology, Tuebingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Erik J Ragsdale

    Department for Evolutionary Biology, Max Planck Institute for Developmental Biology, Tuebingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Natsumi Kanzaki

    Forest Pathology Laboratory, Forestry and Forest Products Research Institute, Tsukuba, Japan
    Competing interests
    The authors declare that no competing interests exist.
  4. Ralf J Sommer

    Department for Evolutionary Biology, Max Planck Institute for Developmental Biology, Tuebingen, Germany
    For correspondence
    ralf.sommer@tuebingen.mpg.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Merijn R Kant, University of Amsterdam, Netherlands

Publication history

  1. Received: November 3, 2014
  2. Accepted: February 3, 2015
  3. Accepted Manuscript published: February 4, 2015 (version 1)
  4. Version of Record published: March 12, 2015 (version 2)

Copyright

© 2015, Susoy et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Vladislav Susoy
  2. Erik J Ragsdale
  3. Natsumi Kanzaki
  4. Ralf J Sommer
(2015)
Rapid diversification associated with a macroevolutionary pulse of developmental plasticity
eLife 4:e05463.
https://doi.org/10.7554/eLife.05463

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