Dissertation Research: Evolutionary origins of gypsophily in Nama (Boraginaceae)

石膏矿藏以物种特有率高和独特的植物群落为特征，正受到商业采矿作业对栖息地破坏的威胁。石膏特有病(石膏特有)在世界各地干旱地区的许多不同属中独立出现，但在大多数情况下，包含大量石膏适应种的属内是否存在单一或多个起源尚不清楚。这项研究将使用独立的核和叶绿体分子数据集来重建Nama(Boraginaceae)的进化史，Nama是一个新大陆属，由53个物种组成，其中包括11个水母类，以检验关于水母属起源和该属内生物地理格局的假设。形态观察将被用来检验NAMA的特征进化，准备所有物种的诊断检索表，并为一组密切相关的NAMA石膏的分类修订提供数据。这项研究的结果将显著增加对石膏特有的进化史和一般基于基质的特有的进化的认识。通过这项研究获得的信息也可能应用于生物多样性保护工作。为了向美国和墨西哥的研究人员提供关于NAMA的生物多样性数据，将在这两个国家的Herbaria保存重复的凭证样本。所有物种的英语和西班牙语诊断检索表，允许在野外或植物标本馆中识别标本，将在网上发布，并以印刷形式对业余和专业植物学家具有最大价值。有机会通过奥斯汀的伯德·约翰逊夫人野花中心与公众分享这项研究的结果，这是德克萨斯大学的一个有组织的研究单位。

Gypsum deposits, characterized by high rates of species endemism and distinctive plant communities, are under threat of habitat destruction from commercial mining operations. Gypsum endemism (gypsophily) has arisen independently in many different genera in arid regions around the world, however, in most cases it is not clear whether there are single or multiple origins within genera containing numerous gypsum-adapted species. This study will use independent nuclear and chloroplast molecular datasets to reconstruct the evolutionary history of Nama (Boraginaceae), a New World genus comprising 53 species, including 11 gypsophiles, to test hypotheses regarding the origins of gypsophily and biogeographic patterns within the genus. Morphological observations will be used to examine character evolution in Nama, prepare diagnostic keys to all species, and provide data for a taxonomic revision of a group of closely related Nama gypsophiles.The results of this research will add significantly to the knowledge of the evolutionary history of gypsum endemics in particular and the evolution of substrate-based endemism in general. Information gained through this study also has potential applications to biodiversity conservation efforts. To make biodiversity data on Nama available to researchers in the United States and Mexico, duplicate voucher specimens will be deposited at herbaria in both countries. Diagnostic keys to all species in English and Spanish, allowing specimens to be identified in the field or herbarium, will be published online and in print to be of maximum value to amateur and professional botanists. Opportunities to share the results of this research with the general public exist through the Lady Bird Johnson Wildflower Center in Austin, an Organized Research Unit of the University of Texas.