Phylogenetic Investigations

The genus Solidago (Asteraceae)

One ongoing effort is concerned with developing suitable molecular (i.e. DNA-based) markers with the intent of elucidating the phylogenetic relationships in the North American species of the genus Solidago L.  There are approximately 95 species in this continent, grouped into six taxonomic sections.  Prior efforts, in collaboration with Drs. Randy Small and Ed Schilling of the University of Tennessee, Mr. James Beck (now of Washington University in St. Louis), and Dr. John Semple of the University of Waterloo in Ontario, focused on using a nuclear DNA marker, the sequence of the Internal Transcribed Spacer (ITS) region between the 5.8S and 28S rRNA genes.  This marker provided little resolution among different Solidago species, but proved to be of utility in providing insights into the phylogeny of the subtribe Solidaginiae and those genera closely related to Solidago.  Future efforts will focus on other nuclear genes as possible markers.

These efforts were funded by a Hesler Endowment Research Award and an EKU University Research Fund Award.

The family Sarraceniaceae

In collaboration with Dr. Rob Naczi of The Claude Phillips Herbarium of Delaware State University, we are now examining the generic relationships within the family Sarraceniaceae, and the species relationships within the family.  Dr. Naczi has obtained DNA samples from several populations of Sarracenia spp. as well as from representatives from several critical outgroups.  Plastid molecular markers will be utilized in an effort to  1) determine the most appropriate outgroup for the genus;  and 2) to address questions of species relationships.  The ultimate goal of this effort is to address questions of species'  phylogenetic relationships and reasons for their particular biogeographical distribution.