Wayt Thomas

My research centers on the plants of the New World tropics and has two basic components, monographic and floristic. My monographic work focuses on the grass-like Cyperaceae (Sedge family), particularly the genus Rhynchospora (the beaked rushes), and the Simaroubaceae (the Tree-of-Heaven family). Although Rhynchospora and the Simaroubaceae are poles apart in relationships and appearance, they share one characteristic: both are groups of plants for which no comprehensive, modern treatment exists. It is, therefore, very difficult to identify specimens of these groups. I enjoy the challenge of making sense of their diversity: of describing the new species, interpreting relationships and biogeographic patterns, and making my knowledge usable by others through monographs and floristic treatments with illustrations and practical keys.

My long term goal in studying Rhynchospora is to produce a comprehensive treatment of the genus for the New World, where it is most diverse and comprises over 200 species. My fascination with the beaked rushes is due to their ecological diversity. Although the majority are wind pollinated, "grassy," plants of tropical savannas, there are species adapted to the deep shade of rainforests, the strong currents of blackwater rivers, and the Sphagnum bogs of boreal North America. Insect pollination has arisen independently at least five times in the genus and some species have adapted to having their seeds dispersed by ants. Evolutionary adaptations in each of these situations has resulted in a remarkable variety of morphological characteristics which I use in determining relationships within the genus.

My objective in studying the Simaroubaceae is to write a monograph of the approximately 100 New World species of the family for publication in Flora Neotropica. In this effort, I am collaborating with two excellent Brazilian botanists. In addition to our study of the systematics of this family, we are also placing emphasis on the unique chemistry of the group and how that is reflected in its ethnobotanical and potential pharmacological uses.

Floristic research gives me an opportunity to study a wide variety of plant species in a specific area. I am studying the rainforests of coastal Bahia, Brazil in collaboration with the Center for Cocoa Research in Bahia. Because of its geographic isolation from other forest types, this rain forest has one of the highest percentages of endemism in the world: over fifty percent of the tree species are found nowhere else. Intensive inventory of the plant species of the Una Biological Reserve in southern Bahia, Brazil, shows that almost 30% of the species occurring in the Reserve have distributions restricted to southern Bahia and northern Espírito Santo. Our research has shown that these forests have a diversity of tree species among the highest in the world. Thus, the assemblage of plant and animal species found here consitute a biota recognized as one of the most unique and endangered on earth. Our studies of this area will produce scientific information critical to making informed decisions about conservation priorities.

Email Address: wthomas@nybg.org
Selected Publications