University of Connecticut
Department of Ecology and Evolutionary Biology
75 N. Eagleville Road, U-3043
Storrs, Connecticut 06269
My graduate research involves the aquatic and wetland plant family Menyanthaceae (Bercht. & Presl), in particular the systematics and taxonomy of species, and the evolution of floral reproductive systems. Species of Menyanthaceae are found worldwide, and are currently divided taxonomically among five genera. The reproductive systems of Menyanthaceae species are of particular interest, because the family contains both hermaphroditic and dioecious species, and many hermaphroditic species are also heterostylous. In addition, species in the genus Nymphoides Ség., while rooted in the substrate, have a floating-leaf habit reminiscent of many other, unrelated aquatic plant lineages.
The five genera of Menyanthaceae are Liparophyllum Hook.f., Menyanthes L., Nephrophyllidium Gilg (= Fauria Franch.), Nymphoides Ség, and Villarsia Vent. Menyanthes and Nephrophyllidium are found only in the northern hemisphere, Liparophyllum and Villarsia are restricted to the southern hemisphere, and Nymphoides has a worldwide distribution, with centers of diversity in Africa, Australia, India, and the Americas. Liparophyllum, Menyanthes, and Nephrophyllidium are monotypic (having only one species each), the genus Villarsia contains 17 species, and Nymphoides has about 40-50 species.
Four genera of Menyanthaceae have an erect inflorescence and grow in wetland habitats. Nymphoides, the most speciose genus, consists mostly of floating-leaved plants, where the leaves serve to keep the flowers above the water surface. I am studying the mechanism through which the floating leaf and inflorescence apparatus arose from a wetland ancestor.
In addition to their diversity in vegetative morphology, species of Menyanthaceae possess an array of reproductive systems, including hermaphroditism, gynodioecy, and dioecy. Heterostyly also occurs in all genera but Liparophyllum, with the majority of species in Nymphoides and Villarsia being heterostylous. Using a phylogenetic framework, I plan to infer the directionality of conversions to and from particular reproductive systems, and address the evolutionary forces promoting changes in floral morphology.
Ph.D. Ecology and Evolutionary Biology
University of Connecticut, Storrs, CT
Major Advisor: Donald H. Les
B.A. Biology / Classics
University of Dallas, Irving, TX
- Tippery, N. P., D. H. Les, D. J. Padgett, and S. W. L. Jacobs. 2007 (submitted). Generic circumscription in Menyanthaceae (Bercht. & Presl): a phylogenetic evaluation. Systematic Botany.
- Les, D. H., S. W. L. Jacobs, N. P. Tippery, L. Chen, M. L. Moody, and M. Wilstermann. 2007 (submitted). Systematics of Vallisneria L. (Hydrocharitaceae Juss.). Systematic Botany.
- Les, D. H., R. S. Capers, and N. P. Tippery. 2006. Introduction of Glossostigma (Phrymaceae) to North America: a taxonomic and ecological overview. American Journal of Botany 93 (6): 927-939.
- Hartman, J. L. IV and N. P. Tippery. 2004. Systematic quantification of gene interactions by phenotypic array analysis. Genome Biology 5: R49.
- Tippery, N.P. and D.H. Les. 2007. Expanding the phylogenetic utility of the internal transcribed spacer (ITS) region using predicted secondary structure. Botany 2007 Abstracts. Botanical Society of America.
- Tippery, N. P., D. H. Les, D. J. Padgett, and S.W.L. Jacobs. 2006. Clades and grades: an evaluation of generic circumscriptions in Menyanthaceae Dumort. (Asterales). Botany 2006 Abstracts. Botanical Society of America.
Teaching and Research Experience
- Teaching Assistant, BIOL 110: Introduction to Botany. 2007. University of Connecticut.
- Student Instructor, Summer Faculty Workshop in Biodiversity and Forensic Genetics. 2006. University of Connecticut.
- Research Assistant, Les Laboratory. 2005-2007. University of Connecticut.
- Teaching Assistant, BIOL 108: Introductory Biology Laboratory. 2003-2005. University of Connecticut.