Plant diversity & evolution

Hi there, and welcome to our lab website!

We are a group of scientists based at the University of Vermont who study plant distributions and evolution, with a focus on understanding the factors underlying their exceptional diversity in the world’s tropics. Our research spans a range of disciplines, and we combine fieldwork, phylogenomics, spatial analyses, and herbarium specimens to address fundamental questions in plant evolution. Much of our work focuses on ferns and lycophytes in Central and South America and the Caribbean, but our interests a bit broader, both geographically and taxonomically.

Interested in joining our group? The application deadline for the University of Vermont’s Ph.D. program in Plant Biology has already passed, but please get in touch about future opportunities in the Testo Lab if you are interested.

I am as Assistant Professor of Plant Biology and Director of the Pringle Herbarium at the University of Vermont. I am broadly interested in understanding the ecology and evolution of land plants, particularly the spore-dispersed vascular plants: ferns and lycophytes. I am especially interested in the role of hybridization and polyploidy as forces shaping fern and lycophyte diversity in the American tropics and diversity of the clubmoss family (Lycopodiaceae). To address these questions, I work extensively with natural history collections and integrate systematics, taxonomy, biogeography, phylogenomics, and functional ecology in my research. See my research page for more!

From 2022-2023, I was the Assistant Curator of Pteridophytes at the Field Museum of Natural History in Chicago, Illinois, USA. While there, I led the curation of the museum’s fern and lycophyte collection, which includes more than 110,000 specimens (including around 1000 types) and holds a particular important collection of ferns from South America.

From 2020-2022, I was a postdoc in the Antonelli Lab at the University of Gothenburg, Sweden. While there, my principal research focus was on modeling extinction risks for the imperiled flora of Hispaniola, the second largest island in the Caribbean. This project integrates natural history collections, biodiversity informatics, remote sensing, conservation, and modeling approaches. I am hoping that this work will help inform conservation efforts in Haiti and the Dominican Republic (the two countries that occupy the island of Hispaniola).

From 2018-2020, I was a postdoc in the Biology Department at the University of Florida, working on the Genealogy of Flagellate Plants with Emily Sessa. We have generated a lot of data through this project and have many ongoing projects resolving the evolutionary histories of thousands of species of bryophytes, lycophytes, ferns, and gymnosperms. We recently published a paper outlining probe development and showing pilot data - it is available here. Other papers from this project include this work on the fern family Thelypteridaceae.