Selection and the direction of phenotypic evolution

  1. François Mallard  Is a corresponding author
  2. Bruno Afonso
  3. Henrique Teotónio  Is a corresponding author
  1. Ecole Normale Superieure, France

Abstract

Predicting adaptive phenotypic evolution depends on invariable selection gradients and on the stability of the genetic covariances between the component traits of the multivariate phenotype. We describe the evolution of six traits of locomotion behavior and body size in the nematode Caenorhabditis elegans for 50 generations of adaptation to a novel environment. We show that the direction of adaptive multivariate phenotypic evolution can be predicted from the ancestral selection differentials, particularly when the traits were measured in the new environment. Interestingly, the evolution of individual traits does not always occur in the direction of selection, nor are trait responses to selection always homogeneous among replicate populations. These observations are explained because the phenotypic dimension with most of the ancestral standing genetic variation only partially aligns with the phenotypic dimension under directional selection. These findings validate selection theory and suggest that the direction of multivariate adaptive phenotypic evolution is predictable for tens of generations.

Data availability

New data, R code for analysis and modeling results is freely accessible and can be found at https://github.com/ExpEvolWormLab/Mallard_Robertson

The following previously published data sets were used

Article and author information

Author details

  1. François Mallard

    Institut de Biologie de l'ENS, Ecole Normale Superieure, Paris, France
    For correspondence
    mallard@bio.ens.psl.eu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2087-1914
  2. Bruno Afonso

    Institut de Biologie de l'ENS, Ecole Normale Superieure, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Henrique Teotónio

    Institut de Biologie de l'ENS, Ecole Normale Superieure, Paris, France
    For correspondence
    teotonio@bio.ens.psl.eu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1057-6882

Funding

European Research Council (ERC-St-243285)

  • Henrique Teotónio

Agence Nationale pour la Recherche (ANR-14-ACHN-0032-01)

  • Henrique Teotónio

Agence Nationale pour la Recherche (ANR-17-CE02-0017-01)

  • Henrique Teotónio

National Science Foundation (PHY-1748958)

  • Henrique Teotónio

Gordon and Betty Moore Foundation (2919.02)

  • Henrique Teotónio

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2023, Mallard 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. François Mallard
  2. Bruno Afonso
  3. Henrique Teotónio
(2023)
Selection and the direction of phenotypic evolution
eLife 12:e80993.
https://doi.org/10.7554/eLife.80993

Share this article

https://doi.org/10.7554/eLife.80993

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