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Department of Integrative Biology
Ph.D. Comprehensive Exam
Audrey Spencer
Ph.D Student
Drs. Ackerfield & Bruederle’s lab, Denver Botanic Gardens
When: Oct. 24, 2023 at 11:00a
Where: SI 4127
Systematics and Biogeography of the Eastern Asian-North American Disjunct Genus, Physocarpus (Rosaceae)
My dissertation research uses Physocarpus, a genus of shrubs in the rose family, to address questions related to the evolutionary and biogeographic histories of vascular plants. I will use restriction site-associated DNA sequencing to investigate the systematics of Physocarpus based on a geographically and taxonomically representative sampling schema. I also intend to clarify the taxonomy of Physocarpus by considering morphological and molecular evidence in an integrative taxonomy framework. Next, I will construct a fossil-calibrated time tree (where branch lengths are correlated with time) to explore the order and timing of divergence within the genus as well as its biogeographical history. Finally, I will investigate the phylogeographic factors contributing to the contemporary intracontinental disjunction of Physocarpus intermedius, including the potential role of glacial refugia.