Understanding how new species form and become isolated from one another is a central goal of evolutionary biology. Changes in chromosome structure, which alter the gene order and content within chromosomes, can play a primary role in the divergence process. Chromosomal rearrangements can prevent hybridization by causing hybrid sterility. They can also prevent gene transfer across species boundaries by packaging together genes that affect suites of adaptive traits. Our projects use monkeyflowers, Mimulus lewisii and M. cardinalis, to investigate the unique role of chromosome change in adaptive divergence and speciation. We will use genetic sequence data and comprehensive genomic analyses to 1) precisely identify the chromosomal changes that distinguish species, 2) examine which genomic regions are responsible for the evolution of species-specific traits, and 3) investigate whether rearranged regions or other adaptive loci are responsible for adaptive evolution across a broader range of species.
Our research will shed light on how ecological adaptation occurs and gives rise to unique species. This work has the potential to overturn our current understanding of adaptation and speciation in plants, which has traditionally focused on the action of single genes, rather than the genome as a whole. We will work with local schools and a science museum to develop interactive activities featuring monkeyflowers to teach young students about floral diversity and evolution. We will also offer abundant opportunities for undergraduates to acquire hands-on training in molecular techniques, plant breeding, quantitative genetics, and genomics.
