2025 Mentors and Projects

Jordan Teisher, Ph.D.
Curator and Director
Herbarium

Research Interests

• Collections management
• Systematics of grasses (Poaceae)

Herbarium DNA – A Complicated History. Teisher is the Director of the MO herbarium, his research focuses on optimizing curatorial activities for the more than 7 million samples housed at the herbarium. Herbarium specimens are increasingly a primary source of DNA for phylogenetic studies trying to complete the tree of life for the world’s plants. However, specimens are often sampled without checking the identifications for accuracy, and DNA sequence repositories like GenBank are disconnected from the specimen databases where identifications are updated and corrected. The result is that DNA sequences and the evolutionary trees resulting from them may have incorrect names attached to them, causing misleading and inaccurate conclusions in the published literature, which may in turn cause further downstream inaccuracies if they are cited and used without consulting the original specimens. The Missouri Botanical Garden herbarium (MO) has kept records of sampling requests for DNA for almost 25 years. From 2001-2023, roughly 15,000 samples were provided from the herbarium in support of over 500 different projects. This project will compare these records with the published literature to locate specimens cited in molecular phylogenetic studies, comparing the current identification of the specimen with 1.) the name published in the study and 2.) the name associated with sequences derived from that specimen on GenBank. By examining the frequency of mismatches between these interrelated sources, the REU intern will contribute valuable information for researchers, collections managers, and database administrators working with taxonomic and molecular sequence data. It is possible for the student participating in this project to receive co-authorship on a publication resulting from this work.