1. Ecology
  2. Evolutionary Biology
Download icon

Variable opportunities for outcrossing result in hotspots of novel genetic variation in a pathogen metapopulation

  1. Anna-Liisa Laine  Is a corresponding author
  2. Benoit Barrès
  3. Elina Numminen
  4. Jukka P Siren
  1. University of Zürich, Switzerland
  2. Université de Lyon, France
  3. University of Helsinki, Finland
  4. Aalto University, Finland
Research Article
  • Cited 6
  • Views 1,351
  • Annotations
Cite this article as: eLife 2019;8:e47091 doi: 10.7554/eLife.47091

Abstract

Many pathogens possess the capacity for sex through outcrossing, despite being able to reproduce also asexually and/or via selfing. Given that sex is assumed to come at a cost, these mixed reproductive strategies typical of pathogens have remained puzzling. While the ecological and evolutionary benefits of outcrossing are theoretically well-supported, support for such benefits in pathogen populations are still scarce. Here, we analyze the epidemiology and genetic structure of natural populations of an obligate fungal pathogen, Podosphaera plantaginis. We find that the opportunities for outcrossing vary spatially. Populations supporting high levels of coinfection -a prerequisite of sex - result in hotspots of novel genetic diversity. Pathogen populations supporting coinfection also have a higher probability of surviving winter. Jointly our results show that outcrossing has direct epidemiological consequences as well as a major impact on pathogen population genetic diversity, thereby providing evidence of ecological and evolutionary benefits of outcrossing in pathogens.

Article and author information

Author details

  1. Anna-Liisa Laine

    Department of Evolutionary Biology and Environmental Studies, University of Zürich, Zürich, Switzerland
    For correspondence
    anna-liisa.laine@ieu.uzh.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0703-5850
  2. Benoit Barrès

    Anses, INRA, USC CASPER, Université de Lyon, Lyon, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6777-0275
  3. Elina Numminen

    Organismal and Evolutionary Biology, University of Helsinki, Helsinki, Finland
    Competing interests
    The authors declare that no competing interests exist.
  4. Jukka P Siren

    Department of Computer Science, Aalto University, Espoo, Finland
    Competing interests
    The authors declare that no competing interests exist.

Funding

European Research Council (281517)

  • Anna-Liisa Laine

European Research Council (724508)

  • Anna-Liisa Laine

Academy of Finland (296686)

  • Anna-Liisa Laine

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

Reviewing Editor

  1. Kayla King, University of Oxford, United Kingdom

Publication history

  1. Received: March 22, 2019
  2. Accepted: June 18, 2019
  3. Accepted Manuscript published: June 18, 2019 (version 1)
  4. Version of Record published: July 30, 2019 (version 2)

Copyright

© 2019, Laine 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.

Metrics

  • 1,351
    Page views
  • 196
    Downloads
  • 6
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)

  1. Further reading

Further reading

    1. Computational and Systems Biology
    2. Ecology
    Tristan Walter, Iain D Couzin
    Tools and Resources

    Automated visual tracking of animals is rapidly becoming an indispensable tool for the study of behavior. It offers a quantitative methodology by which organisms' sensing and decision-making can be studied in a wide range of ecological contexts. Despite this, existing solutions tend to be challenging to deploy in practice, especially when considering long and/or high-resolution video-streams. Here, we present TRex, a fast and easy-to-use solution for tracking a large number of individuals simultaneously using background-subtraction with real-time (60Hz) tracking performance for up to approximately 256 individuals and estimates 2D visual-fields, outlines, and head/rear of bilateral animals, both in open and closed-loop contexts. Additionally, TRex offers highly-accurate, deep-learning-based visual identification of up to approximately 100 unmarked individuals, where it is between 2.5-46.7 times faster, and requires 2-10 times less memory, than comparable software (with relative performance increasing for more organisms/longer videos) and provides interactive data-exploration within an intuitive, platform-independent graphical user-interface.

    1. Ecology
    2. Genetics and Genomics
    Katie Hinde et al.
    Feature Article

    March Mammal Madness is a science outreach project that, over the course of several weeks in March, reaches hundreds of thousands of people in the United States every year. We combine four approaches to science outreach – gamification, social media platforms, community event(s), and creative products – to run a simulated tournament in which 64 animals compete to become the tournament champion. While the encounters between the animals are hypothetical, the outcomes rely on empirical evidence from the scientific literature. Players select their favored combatants beforehand, and during the tournament scientists translate the academic literature into gripping “play-by-play” narration on social media. To date ~1100 scholarly works, covering almost 400 taxa, have been transformed into science stories. March Mammal Madness is most typically used by high-school educators teaching life sciences, and we estimate that our materials reached ~1% of high-school students in the United States in 2019. Here we document the intentional design, public engagement, and magnitude of reach of the project. We further explain how human psychological and cognitive adaptations for shared experiences, social learning, narrative, and imagery contribute to the widespread use of March Mammal Madness.