1. Evolutionary Biology
  2. Genetics and Genomics
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Introgression shapes fruit color convergence in invasive Galápagos tomato

  1. Matthew JS Gibson  Is a corresponding author
  2. Maria de Lourdes Torres
  3. Yaniv Brandvain
  4. Leonie Moyle
  1. Indiana University, United States
  2. Universidad San Francisco de Quito; Galapagos Science Center, Ecuador
  3. University of Minnesota, United States
Research Article
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Cite this article as: eLife 2021;10:e64165 doi: 10.7554/eLife.64165

Abstract

Invasive species represent one of the foremost risks to global biodiversity. Here, we use population genomics to evaluate the history and consequences of an invasion of wild tomato-Solanum pimpinellifolium-onto the Galápagos islands from continental South America. Using >300 archipelago and mainland collections, we infer this invasion was recent and largely the result of a single event from central Ecuador. Patterns of ancestry within the genomes of invasive plants also reveal post-colonization hybridization and introgression between S. pimpinellifolium and the closely related Galapagos endemic Solanum cheesmaniae. Of admixed invasive individuals, those that carry endemic alleles at one of two different carotenoid biosynthesis loci also have orange fruits-characteristic of the endemic species-instead of typical red S. pimpinellifolium fruits. We infer that introgression of two independent fruit color loci explains this observed trait convergence, suggesting that selection has favored repeated transitions of red to orange fruits on the Galapagos.

Data availability

Raw, demultiplexed ddRAD reads have been deposited under NCBI BioProject PRJNA661300 and will be available once processed by NCBI. Genotype files, associated datasets, and analysis scripts have been deposited on Dryad (https://doi.org/10.5061/dryad.2v6wwpzkm).Additionally, data posted to Dryad can also be accessed at https://github.com/gibsonMatt/galtom.

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Matthew JS Gibson

    Department of Biology, Indiana University, Bloomington, United States
    For correspondence
    gibsomat@indiana.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7855-1628
  2. Maria de Lourdes Torres

    Colegio de Ciencias Biológicas y Ambientales, Laboratorio de Biotecnología Vegetal; Universidad San Francisco de Quito and University of North Carolina at Chapel Hill, Universidad San Francisco de Quito; Galapagos Science Center, Quito, Ecuador
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7207-4568
  3. Yaniv Brandvain

    University of Minnesota, St Paul, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Leonie Moyle

    Department of Biology, Indiana University, Bloomington, United States
    Competing interests
    The authors declare that no competing interests exist.

Funding

National Science Foundation (IOS 1127059)

  • Leonie Moyle

Indiana University Bloomington (Brackenridge)

  • Matthew JS Gibson

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

Reviewing Editor

  1. Hernán A. Burbano, University College London, United Kingdom

Publication history

  1. Received: October 20, 2020
  2. Accepted: June 23, 2021
  3. Accepted Manuscript published: June 24, 2021 (version 1)
  4. Version of Record published: July 21, 2021 (version 2)

Copyright

© 2021, Gibson 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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