DISSERTATION RESEARCH: Systematics of Cupressus and Chamaecyparis (Cupressaceae)

康奈尔大学的Kevin Nixon博士和Damon Little先生获得了一笔赠款，用于研究柏属(柏属)与近缘物种如侧柏(Thuja)和刺柏(Juniperus)的进化关系。这些树种因其诱人的常绿树叶和宜人的“雪松”气味而被广泛种植。他们的木材具有一定的经济价值，因为它的耐用性和抗腐蚀性(例如，用于铅笔、雪松箱子、壁板、甲板和屋顶瓦片)。由于地理分布狭窄，一种柏树被美国政府列为濒危物种，另一种被列为濒危物种。这些物种的DNA序列和形态特征将被用来推断进化历史和划定柏树的物种(关于物种的数量存在很大的争议)。这项研究的结果将突出这些物种的诊断特征，并为专家和非专家(例如，林学家、植物育种者、园艺学家、生态学家等)提供鉴定检索表和其他信息。可以很容易地识别样本。此外，还将提供所有柏树种类的完整描述。其他专家将能够利用在这项研究过程中开发的工具来研究其他针叶树的进化。

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.