REU: Systematics and Phylogeny of Madagascan and African Dalechampia (Euphorbiaceae)

达勒坎皮是一品红属(大戟科)的一种藤本植物，常见于亚洲、非洲和美洲的热带低地。虽然现在对新大陆物种的物种多样性、系统发育关系和传粉生物学了解很多，这在很大程度上是因为斯科特·阿姆布鲁斯特博士在过去十年中所做的研究，但对旧大陆物种的了解相对较少。Dalechampia被用作研究热带植物如何对特殊传粉者产生的选择压力做出反应的模式系统。必须将旧大陆物种整合到这些研究中，以完成整个属的系统发育分析。此外，旧大陆和新大陆热带地区准确的植物区系名录(用于作出管理和保护决定)取决于常见物种的可靠分类信息，如达勒坎皮亚。在旧大陆，达勒坎皮亚人在马达加斯加和南部非洲最为多样化。阿姆布鲁斯特博士将在该地区收集植物标本和液体保存材料，以进行形态和生化分析，包括分析授粉蜜蜂使用的植物产生的不寻常的树脂和芳香化合物。还将观察授粉动物的行为。形态数据将使用分支学方法进行分析，以确定可能的系统发育树，这些树表明了东半球分类群之间以及东半球和新大陆组之间的关系。这些结果将改进大麦属植物的分类系统，指明新旧大陆物种进化中可能的迁徙途径，并确定在这些植物中发现的各种授粉机制的起源。

Dalechampia is a genus of vines of the poinsettia family (Euphorbiaceae) common throughout the lowland tropics in Asia, Africa, and the Americas. Although much is now known about the species diversity, phylogenetic relationships, and pollination biology of the New World species, in large part because of Dr. Scott Armbruster's studies over the last ten years, relatively little is known about Old World species. Dalechampia is being employed as a model system for the study of how tropical plants evolve in response to selective pressures generated by specialized pollinators. Old World species must be integrated into these studies to complete a phylogenetic analysis of the entire genus. Furthermore, accurate floristic inventories (used in making management and conservation decisions) of tropical regions of the Old World as well as the New depend on reliable taxonomic information for common species such as Dalechampia. In the Old World, Dalechampia is most diverse in Madagascar and southern Africa. Dr. Armbruster will collect herbarium specimens in this region along with liquid-preserved material, for morphological and biochemical analyses, including analyses of the unusual resins and fragrance compounds produced by the plants and used by pollinating bees. Observations of the behavior of pollinating animals will also be made. Morphological data will be analyzed using cladistic methods to determine likely phylogenetic trees that show relationships among Old World taxa and between Old and New World groups. These results will improve the classification system for Dalechampia, indicate likely migratory pathways in the evolution of Old and New World species, and determine the origins of the various pollination mechanisms found in these plants.