Understanding the generation of biodiversity involves figuring out how and why speciation occurs. Speciation involves the buildup of barriers to reproduction between diverging species. This buildup can result from the interplay of evolutionary forces such as natural selection and gene flow. This research investigates these evolutionary forces in a group of three native Texas Phlox wildflowers. Focusing on these three species, the research will determine how and why reproductive isolation evolves. Across Texas, these species of wildflowers can be found growing together in populations and hybridizing. This research involves a detailed investigation of what drives the evolution of traits to decrease hybridization between one pair of species and prevents the evolution of these traits in another pair. This research combines ecological studies with genetic and genomic studies. By doing so, it will test long standing hypotheses about how and why species form. This project integrates undergraduate students in a course-based research experience. This experience will allow students to study speciation hands-on and learn about the scientific method. By working with the local natural history museum, this project will engage K-12 grade students and teachers in plant evolution-based activities.
This project investigates how selection, gene flow, and recombination contribute to the evolution of reproductive isolation between co-occurring species. Phlox drummondii co-occurs with two closely related Phlox species but has evolved increased reproductive isolation with only one of these two species. To determine why reproductive isolation evolves with one species and not the other this project will measure the cost of hybridization. Further, the research will measure the strength of existing barriers to reproduction and the amount and direction of gene flow between species. This project integrates field-based studies of pollinator attraction with greenhouse studies of controlled matings and hybrid success. In addition, it will include detailed genomic studies to investigate the genetic architecture of reproductive isolation and gene flow between species.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
