To understand speciation, we must understand both the genetics and ecology of reproductive isolation. Speciation - particularly in plants - often involves ecogeographic isolation, in which populations adapt to different environmental conditions across a geographic range, thus reducing, but not always eliminating, gene flow. When gene flow occurs, it should weaken differentiation between species, potentially breaking down species barriers. Nevertheless, examples abound across the tree of life of speciation and species maintenance despite hybridization, ranging from hominids to butterflies to plants. How, then, is differential adaptation and species identity maintained in the face of gene flow?

My dissertation integrates ecological and genetic investigation to answer this question in a pair of recently diverged (~1mya) tropical herbs with a natural hybrid zone: Costus allenii and C. villosissimus (left). It is built around three research aims: 1) characterize differential abiotic adaptation 2) characterize differential biotic adaptation, and 3) characterize geographic and genomic patterns of introgression and how they are influenced by the genetic architecture of differential adaptations. Learn more about each through the links below!