Dr. Elizabeth A. Zimmer

Curator, Department of Systematic Biology

Phone (301) 238-1118

Fax (301) 238-3059

Email zimmer@lab.si.edu

Research Areas:

The majority of my present research projects deal with studies of the pattern and process of molecular evolution in green plants. When I began my own postdoctoral work in 1980, I developed nuclear ribosomal genes as a good model for both phylogenetic and evolutionary process studies. In order to understand the patterns elucidated by our work, we collaborated with plant systematists and paleobotanists on syntheses of organismal and molecular phylogenies. Over the next five years, we are continuing to use ribosomal and chloroplast gene markers for molecular systematic studies of key groups such as the Asteraceae, Gesneriaceae and several Pacific genera. These projects involve postdoctoral fellows and curators in the Department of Botany at NMNH (Funk, Skog and Wagner, respectively). Other assays of plant genetic diversity (e.g., AFLP, ISSR, random cDNA sequences and microsatellites) are in development for application to species and population level questions.

Among the specific projects ongoing in my group here at the Smithsonian are the following:

1. Comparison of phylogenies for key groups (especially the Winteraceae, Gesneriaceae and certain tribes of the Asteraceae). Coordination and comparison of rDNA data sets for these groups with data sets for chloroplast genes.

2. Comparison of methods for examining lower level taxonomic questions (e.g., AFLP vs. ITS vs. intron sequences in resolving relationships among Hawaiian taxa).

3. Assessment of gesneriad and basal angiosperm systems as good lineages in which to initiate comparative developmental studies

4. The American Roots of English Gardens, application of AFLP technology to assessment of popular herbaceous cultivars

5. Quantitation of the types of change observed through comparative rDNA sequencing--e.g. of the types of base substitutions that predominate, of the degree of length variation, of the likelihood of change in stem vs. loop sequences given a secondary structure model for plant rRNAs.

Selected Publications

Qiu, Y.-L., Lee, J., Bernasconi-Quadroni, F., Soltis, D., Soltis, P., Zanis, M., Zimmer, E., Chen, Z., Savolainen, V. and Chase, M. 1999. "The earliest angiosperms: Evidence from mitochondrial, plastid and nuclear genomes." Nature, 402, 404-407.

Hershkovitz, M.A., Zimmer, E.A. and Hahn, W.J. (1999) "Ribosomal DNA and angiosperm systematics." In: Molecular Systematics and Plant Evolution, P. Hollingsworth, R. Bateman and R. Gornall, eds., Taylor & Francis, 268-326.

Kuzoff, R.K., Sweere, J. A., Soltis, D., Soltis, P. and Zimmer, E.A. (1998) "The phylogenetic potential of entire 26S rDNA sequences in plants." Mol. Biol. Evol. 15, 251-263.

Hershkovitz, M.A. and Zimmer, E.A. (1997) "On the evolutionary origins of the cacti" Taxon, 46, 217-232.

Soltis, D.E., Soltis, P.S., Nickrent, D.L., Johnson, L.A., Hahn, W.J., Hoot, S.B., Sweere, J.A., Kuzoff, R.K., Kron, K.A., Chase, M.W., Swensen, S.M., Zimmer, E.A., Chaw, S.-M., Gillespie, L.J., Kress, W.J. and Sytsma, K.J. (1997) "Angiosperm phylogeny inferred from 18S ribosomal DNA sequences." Ann. Mo. Bot. Gdn., 84, 1-49.

Hershkovitz, M.A. and Zimmer, E.A. (1996) "Conservation patterns in angiosperm rDNA-ITS2 sequences" Nucleic Acids Research, 24, 2857-2867.

Wen, J. and Zimmer, E.A. (1996) "Phylogeny of Panax L. (the Ginseng Genus, Araliaceae): Inference from ITS sequences of nuclear ribosomal DNA." Molecular Phylogenetics and Evolution, 5, 167-177.

Bult, C.J., Sweere, J.A. and Zimmer, E.A. (1995) "Cryptic sequence simplicity, nucleotide composition bias, and molecular coevolution in the large subunit of ribosomal DNA in plants." Ann. Mo. Bot. Gdn., 82, 235-246.

Zimmer, E.A. (1995) "The New Morphology: Integrative Approaches." Aliso, 14, 233-235.

Zimmer, E.A. (1994) "Perspectives on future applications of experimental biology to evolution." In: Molec. Ecol. and Evol.: Approaches and
Applications, eds. B. Schierwater, B. Streit, G. Wagner, R. DeSalle. Birkhauser Verlag, 607-616.

Doyle, J.A., Donoghue, M.J. and Zimmer, E.A. (1994) "Integration of morphological and ribosomal RNA data on the origin of angiosperms." Ann. Mo. Bot. Gdn., 81(2), 419-450.

Zimmer, E., White, T., Cann, R. and Wilson, A., eds. (1993) Methods in Molecular Evolution: Producing the Biochemical Data, Methods in Enzymology, 224, 725 pp.

Suh, Y., Thien, L., Reeve, H. and Zimmer, E. (1993) "Molecular evolution and phylogenetic implications of internal transcribed spacer sequences of ribosomal DNA in Winteraceae." Am. Jnl. Bot. 80, 1042-1055.