Introgression shapes fruit color convergence in invasive Galápagos tomato
- Indiana University, United States
- Universidad San Francisco de Quito; Galapagos Science Center, Ecuador
- University of Minnesota, United States
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.
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Data from: Reconstructing the history and biological consequences of a plant invasion on the Galápagos islandsDryad Digital Repository 10.5061/dryad.2v6wwpzkm.
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Phylogenomics reveals three sources of adaptive variation during a rapid radiationDryad Digital Repository 10.5061/dryad.182dv.
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Regional differences in the abiotic environment contribute to genomic divergence within a wild tomato speciesDryad Digital Repository 10.5061/dryad.8gtht76k4.
Article and author information
Author details
Maria de Lourdes Torres
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.
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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Introgression shapes fruit color convergence in invasive Galápagos tomato
eLife 10:e64165.
https://doi.org/10.7554/eLife.64165
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