Jonathan Qu L&S Sciences
Untangling evolutionary relationships among Polystichum californicum and its progenitors
While speciation (the formation of new species) is often thought of as occurring through the splitting of one species into two, species can arise through other mechanisms, such as allopolyploidy. Allopolyploidy occurs through the formation of a hybrid between two species, followed by genome duplication. This mechanism of speciation is common in plants, including in crop plants. While artificial allopolyploid plants have been studied in the laboratory, allopolyploidy remains understudied in natural populations. Polystichum californicum is a fern species thought to have originated via multiple independent allopolyploidization events throughout its range along the West Coast. In my Integrative Biology honors thesis, I will collect samples of Polystichum californicum and its possible progenitor species from throughout their ranges, and analyze their DNA to answer the questions of which species Polystichum californicum arose from, and whether it arose multiple times (possibly from multiple progenitors). Through this work I hope to contribute to a better understanding of the evolutionary process of allopolyploidization, and a better understanding of the biodiversity within the genus Polystichum.