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。这笔拨款将改善雷蒙娜·沃尔斯的博士论文研究。本研究综合了系统发育学、物种分布模型和植物解剖学和生理学的技术，探讨了有关性状和物种多样性的问题。它的目的是检验这样一种假设，即区域气候因素的自然选择导致墨西哥山药的叶形多样化，山药是一种广泛分布的草本植物藤本植物。更多的物种将被抽样，以提供关于该属内进化关系的更准确的假说。这些信息需要与物种定位数据和来自普通花园研究的生理测量相结合，以在气候耐受性和进化史的背景下检查形式-功能关系。两个叶功能的指示器。水分利用效率和叶片导水率，将在大量植物的自然环境中进行测量。这将有可能检验额外的假设，即墨西哥山药降水生态位的保守性或进化伴随着叶功能的保守性或进化，以及叶功能的保守性或进化与特定的叶片轨迹组相关联。这项研究的更广泛的影响包括社会效益和教育效益。墨西哥山药含有一种主要热带粮食作物(山药)的野生近缘植物，以及许多用于药物化合物的收获物种。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，具有重要的经济和社会意义。这项研究正在生成一个庞大的数据库，其中包括植物位置、表型特征、环境容忍度、植物学图像和DNA序列，这些数据库将通过在线数据库发布给科学界。国际合作是这项研究不可分割的一部分，几次墨西哥之行导致了与墨西哥科学家和学生的广泛互动。最后，超过15名本科生参与了这项研究，其中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.