DISSERTATION RESEARCH: Climate as a driver of leaf trait diversification in Mexican Dioscorea

在R. Geeta博士的指导下，纽约州立大学石溪分校获得了一笔赠款，用于研究气候与草本植物进化的关系。该资助将提高Ramona Walls博士论文的研究水平。本研究通过整合系统发育、物种分布建模和植物解剖学和生理学等技术来解决性状和物种多样化的问题。它的设计是为了验证一个假设，即区域气候因素的自然选择是墨西哥薯蓣（一种广泛分布的草本藤本植物）叶片形式多样化的原因。将对其他物种进行采样，以提供更准确的属内进化关系假设。这些信息将与物种位置数据和来自普通花园研究的生理测量相结合，以检查气候耐受性和进化史背景下的形式-功能关系。两叶功能指标。水分利用效率和叶片水力导度，将在大量植物的自然环境中进行测量。这将有可能验证墨西哥薯蓣降水生态位的保守性或进化伴随着叶片功能的保守性或进化，以及叶片功能的保守性或进化与特定的叶片性状集有关的额外假设。这项研究的更广泛影响包括社会和教育效益。墨西哥薯蓣含有一种主要的热带粮食作物（山药）的野生近缘种，以及许多用于制药化合物的品种。因此，了解这一群体的进化关系，以及气候对其变异和分布的影响，在经济和社会上都具有重要意义。这项研究正在产生一个大型数据库，包括植物位置、表型特征、环境耐受性、植物图像和DNA序列，将通过在线数据库的出版物提供给科学界。国际合作是这项研究的一个组成部分，我多次前往墨西哥，与墨西哥科学家和学生进行了广泛的交流。最后，超过15名本科生参与了这项研究，大多数来自代表性不足的群体。

A grant has been awarded to the State university of New York at Stony Brook under the direction of Dr. R. Geeta to study the relationship of climate to the evolution of herbaceous plants. The grant will improve the doctoral dissertation research of Ramona Walls. This research addresses questions about trait and species diversification by integrating techniques from phylogenetics, species distribution modeling and plant anatomy and physiology. It is designed to test the hypothesis that natural selection by regional climate factors is responsible for the diversification of leaf forms in Mexican Dioscorea, a widespread group of herbaceous vines. Additional species will be sampled to provide a more accurate hypothesis of evolutionary relationships within the genus. This information with be combined with species locality data and physiological measurements from a common garden study to examine form-function relationships in the context of climate tolerances and evolutionary history. Indicators of two leaf functions. water use efficiency and leaf hydraulic conductance, will be measured in a large number of plants in their natural environment. This will make it possible to test the additional hypotheses that the conservatism or evolution of precipitation niches in Mexican Dioscorea is accompanied by the conservatism or evolution of leaf functions, and that the conservatism or evolution of leaf functions is linked to specific sets of leaf traits.The broader impacts of this research include both social and educational benefits. Mexican Dioscorea contain the wild relatives of a major tropical food crop (yams) as well as many species that are harvested for pharmaceutical compounds. Understanding the evolutionary relationships in this group, and the impacts of climate on its variation and distribution, is therefore economically and socially important. This research is generating a large data-base of plant localities, phenotypic characteristics, environmental tolerances, botanical images and DNA sequences that will be available to the scientific community through publication in online databases. International collaboration is an integral part of this research, and several trips to Mexico have lead to extensive interactions with Mexican scientists and students. Finally, more than fifteen undergraduate students have participated in this research, most from underrepresented groups.