Curator/Director of Graduate Studies
• Broad scale aspects of plant evolution
• Systematics and phylogeny of Onagraceae
• Impacts of human-influenced environmental changes
• Floral phenology and pollination biology
Web Page: MBG
Variation in seed morphology in the genus Clarkia and related genera. Hoch is the coordinator of the Garden’s graduate education program and has served as PI and, in the past three years, co-PI of the REU program. His research foci include the evolution of Onagraceae and long-term phenological studies. Species of the well-known genus Clarkia (Onagraceae) and several closely related genera (Gayophytum, Chylismiella, and Taraxia) have varied and unusual ornamentation on their seed coats. The student will remove seeds from MO herbarium specimens of all species in this Clarkia clade, obtain measurements, and take images of the seeds using the SEM, thereby documenting their variation. Using a recent detailed molecular phylogeny of Onagraceae, which proposes novel relationships within the Clarkia clade, the student will determine if seed coat characters support that phylogeny, and/or if seed coat variation may be related to ecological differences among species. Using seeds from a subset of species, the student will also test for the presence of lipids and proteins in the crests, knobs, and other seed ornamentation (using histological and chemical examination) to test the hypothesis that these features function as an elaiosome, thereby contributing to seed dispersal by ants.