Research Training Program

Smithsonian Institution
National Museum of Natural History

PROJECT SUMMARY
1996

Brian S. Wysor
Southampton College
Southampton, New York
James N. Norris, Ph.D.
Supervising Scientist
Department of Botany
"An ecologist at heart, I have had very little exposure to the field of systematics and taxonomic classification of organisms. Through this program, however, I have realized the importance of systematics in ecological research and expect that I will direct my future research endeavors to incorporate a systematic approach to ecological questions. "

Taxonomic and nomenclature confusion in the
widely distributed red alga, Laurencia obtusa

ABSTRACT
Laurencia obtusa is an economically important species of marine red algae with a broad geographic range. It is reported in the Atlantic, Indian and Pacific Oceans as well as the Australian, Caribbean and Mediterranean Seas and the natural products extracted from this marine plant represent economic potential in the form of pharmaceutical and industrial products to the nations whose waters it inhabits. Studies on the natural products of members of the Laurencia group of red algae indicate that certain compounds may only be produced by certain species. The "chemical signature," a single compound known only for a single species, becomes a useful research tool to scientists who are trying to determine species identification, composition of community structure, or for systematic and phylogenetic studies with mariculture applications (a marine equivalent to agriculture and plant domestication). The ecology and biology of this alga, however, must be considered in light of the chemical nature before chemical signatures can be considered absolute. Differences in the chemical nature between specimens of Laurencia obtusa collected in the Caribbean Sea and those from English waters prompted this comparative study of the anatomy of the algae from both locations in order to corroborate or repudiate the findings of the natural products chemistry. Cross sections of Caribbean and English specimens were stained and preserved on microscope slides for observation through the light microscope. The size and shape of different cell types was documented in addition to characterizing the reproductive structures of mature plants. Observations revealed subtle differences in anatomical features of Laurencia obtusa from the Caribbean Sea and England, however, further studies which consider the developmental biology of the alga in light of functional responses to environmental stimuli will be necessary in order to substantiate the findings of this study.

Letter of Gratitude