Evolutionary Consequences of Natural Hybridization
Despite the long-standing view that hybridization has only transient evolutionary effects, it can be a creative force in evolution. For example, homoploid and polyploid hybrid speciation have been documented in many plant and animal species, and adaptive introgression is becoming more widely recognized as a source of genetic and phenotypic novelty across diverse systems. This is especially true when hybridization can occur among several closely related taxa, such as is the case in recent evolutionary radiations. However, we still have relatively few examples that have demonstrated the creative role of hybridization during the early stages of divergence and incipient speciation.
The Mimulus aurantiacus species complex (Phrymaceae) provides an excellent opportunity to examine hybridization's role in evolution - over both space and time - as distinct taxa appear to hybridize whenever their ranges come into contact. However, hybridization has also complicated the study of evolution and ecology of these plants. Despite being phenotypically and ecologically distinct from one another, all taxa in the complex are at least partially interfertile and hybridize in narrow areas if their geographic ranges overlap. This has created extensive controversy over the taxonomic status of these entities, with anywhere from from 2 to 14 different species, subspecies, and/or varieties described over the past 60 years. We are working to resolve the relationships among populations using landscape genomic and phylogenetic methods.
With this information in hand, we also ask questions about the role of hybridization in evolution. For example:
We are addressing these and other questions using population genomics, QTL mapping, cline analyses, and whole-genome re-sequencing studies.
The Mimulus aurantiacus species complex (Phrymaceae) provides an excellent opportunity to examine hybridization's role in evolution - over both space and time - as distinct taxa appear to hybridize whenever their ranges come into contact. However, hybridization has also complicated the study of evolution and ecology of these plants. Despite being phenotypically and ecologically distinct from one another, all taxa in the complex are at least partially interfertile and hybridize in narrow areas if their geographic ranges overlap. This has created extensive controversy over the taxonomic status of these entities, with anywhere from from 2 to 14 different species, subspecies, and/or varieties described over the past 60 years. We are working to resolve the relationships among populations using landscape genomic and phylogenetic methods.
With this information in hand, we also ask questions about the role of hybridization in evolution. For example:
- What is the role of introgression in evolutionary divergence?
- How has hybridization shaped the complex evolutionary history of divergence?
- Why do some taxa show evidence of phenotypic hybridization when their genomes do not?
We are addressing these and other questions using population genomics, QTL mapping, cline analyses, and whole-genome re-sequencing studies.