1. Ecology
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A fitness trade-off between seasons causes multigenerational cycles in phenotype and population size

Research Article
  • Cited 4
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Cite this article as: eLife 2017;6:e18770 doi: 10.7554/eLife.18770

Abstract

Although seasonality is widespread and can cause fluctuations in the intensity and direction of natural selection, we have little information about the consequences of seasonal fitness trade-offs for population dynamics. Here we exposed populations of Drosophila melanogaster to repeated seasonal changes in resources across 58 generations and used experimental and mathematical approaches to investigate how viability selection on body size in the non-breeding season could affect demography. We show that opposing seasonal episodes of natural selection on body size interacted with both direct and delayed density dependence to cause populations to undergo predictable multigenerational density cycles. Our results provide evidence that seasonality can set the conditions for life-history trade-offs and density dependence, which can, in turn, interact to cause multigenerational population cycles.

Article and author information

Author details

  1. Gustavo Sigrist Betini

    Department of Integrative Biology, University of Guelph, Guelph, Canada
    For correspondence
    gsbetini@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0707-4128
  2. Andrew G McAdam

    Department of Integrative Biology, University of Guelph, Guelph, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Cortland K Griswold

    Department of Integrative Biology, University of Guelph, Guelph, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Ryan Norris

    Department of Integrative Biology, University of Guelph, Guelph, Canada
    Competing interests
    The authors declare that no competing interests exist.

Funding

Ontario Graduate Scholarship

  • Gustavo Sigrist Betini

Natural Sciences and Engineering Research Council of Canada

  • Andrew G McAdam
  • Cortland K Griswold
  • Ryan Norris

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

Reviewing Editor

  1. Lutz Becks, Max Planck Institute for Evolutionary Biology, Germany

Publication history

  1. Received: June 13, 2016
  2. Accepted: February 6, 2017
  3. Accepted Manuscript published: February 6, 2017 (version 1)
  4. Accepted Manuscript updated: February 7, 2017 (version 2)
  5. Version of Record published: March 7, 2017 (version 3)

Copyright

© 2017, Betini 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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