Document Type
Article
Department/Program
Biology
Journal Title
Evolution
Pub Date
2015
Volume
69
Issue
6
First Page
1487
Abstract
Whole genome duplication (polyploidization) is a mechanism of instantaneous species formation that has played a major role in the evolutionary history of plants. Much of what we know about the early evolution of polyploids is based upon studies of a handful of recently formed species. A new polyploid hybrid (allopolyploid) species Mimulus peregrinus, formed within the last 140 years, was recently discovered on the Scottish mainland and corroborated by chromosome counts. Here, using targeted, high-depth sequencing of 1200 genic regions, we confirm the parental origins of this new species from M. x robertsii, a sterile triploid hybrid between the two introduced species M. guttatus and M. luteus that are naturalized and widespread in the United Kingdom. We also report a new population of M. peregrinus on the Orkney Islands and demonstrate that populations on the Scottish mainland and Orkney Islands arose independently via genome duplication from local populations of M. x robertsii. Our data raise the possibility that some alleles are already being lost in the evolving M. peregrinus genomes. The recent origins of a new species of the ecological model genus Mimulus via allopolyploidization provide a powerful opportunity to explore the early stages of hybridization and genome duplication in naturally evolved lineages.
Recommended Citation
Vallejo-Marin, Mario; Buggs, Richard J. A.; Cooley, Arielle M.; and Puzey, Joshua R., Speciation by genome duplication: Repeated origins and genomic composition of the recently formed allopolyploid species Mimulus peregrinus (2015). Evolution, 69(6), 1487-1500.
https://doi.org/10.1111/evo.12678
DOI
https://doi.org/10.1111/evo.12678