DISSERTATION RESEARCH: Systematics of Cupressus and Chamaecyparis (Cupressaceae)

Cornell Univ - State: Awds Made Prior May 2010, Ithaca NY

Investigators

Abstract

A grant has been awarded to Dr. Kevin Nixon and Mr. Damon Little at Cornell University to study the evolutionary relationships of the genus Cupressus (cypress) and closely related species such as arborvitae (Thuja) and junipers (Juniperus). These species are widely cultivated for their attractive evergreen foliage and pleasant "cedar" scent. Their wood is of some economic importance due to its durability and resistance to rot (used in e.g., pencils, cedar chests, siding, decks, and roofing shingles). Due to their narrow geographic distributions, one species of cypress is classified by the United States government as endangered and another is listed as threatened. DNA sequences and morphological characteristics of these species will be used to infer the evolutionary history and delimit the species of cypress (there is great controversy concerning the number of species). Other questions that will be investigated include the evolution specialized adaptations to extreme habitat types, evolution of seed dispersal mechanisms, and hybridization between cypress species. The result of this research will highlight diagnostic characteristics of these species and provide identification keys and other information so specialists and non-specialists (e.g., foresters, plant breeders, horticulturists, ecologists, etc.) can easily identify specimens. In addition a complete description of all cypress species will be provided. Other specialists will be able to the tools developed during the course of this research to study evolution in other conifers.