Associate Professor, Plant Systematics

George Mason University



line decor
line decor



My research focuses on understanding the systematic biology of flowering plants. This field of inquiry includes the study of taxonomy (i.e., species discovery and description), the study of phylogeny (i.e., evolutionary relationships among species), and the study of evolutionary processes (e.g., speciation, historical biogeography). Much of my research centers on the systematics of the frankincense and myrrh family, Burseraceae. However, members of my lab have pursued systematics projects involving a range of plant taxa across the globe, from Himalayan sunflowers to the Virginian saltmarsh mallow.

I am pictured above holding a herbarium sheet of Chrysogonum virginianum (Asteraceae), a native wildflower known as "Green-and-Gold." This name also describes Mason's university colors! Photo credit: Evan Cantwell, GMU.

In addition to my research and teaching responsibiIities, I am director of the Ted R. Bradley Herbarium at GMU and am engaged in making this valuable resource of information about the Virginia flora more accessible via the internet. Posted here is a recent presentation to the Virginia Native Plant Society about this ongoing digitization initiative.

Media mentions about my research:

Radio interview on “With Good Reason” about the Keys to the Cabinet digitization initiative. Aired national-wide on National Public Radio affiliates. July 29, 2016. Streamable at:

Mason Students are Turning Dried Blossoms into Database: 06/12/2015

Mason Leads Initiative to Record, Digitize Virginia Plant Life: 10/24/2014

Native Plant Society Donates 'Flora of Virginia' to Mason: 04/11/2013

Seeing Both the Forest and the Trees: 10/18/2010

Mason Faculty Members Explore the World in Efforts to Study Environmental Issues: 08/04/2008

Natural Walk Introduces Community to Another Side of Campus:

Mason's Herbarium Is a Treasure Trove for Scholars: 02/21/2007

Research Experience Shortens Learning Curve for Grad Student: 10/26/2006



Read a recent paper:
Gostel, M., Phillipson, P. and A. Weeks. 2016. Phylogenetic reconstruction of the myrrh genus, Commiphora (Burseraceae), reveals multiple radiations in Madagascar and clarifies infrageneric relationships. Systematic Botany 41(1): 67 – 81.

View plants from my most recent trip:
Melampyrum in W Canada - 2015

Opportunites for GMU student researchers are available:
contact me for details.