CAREER: Gypsum Endemics of the Chihuahuan Desert: Exploring the origins and diversification of an edaphic flora using comparative phylogenetics and phylogeography

这个项目结合了一个积极的研究计划，以了解受限于不寻常土壤的植物的进化，同时也同样积极地努力提高高中生和大学生对进化生物学核心概念的理解。只生长在特殊土壤上的植物物种，如蛇纹岩土壤(金属浓度高)、沼泽(低pH值)或蒸发岩(高盐度)，构成了全球植物生物多样性的相当大比例，但令人惊讶的是，人们对它们的进化史知之甚少。例如，限制在这些不同寻常的土壤上的植物谱系是否会在很长一段时间的进化中持续存在？同样，这些血统是如何应对过去的气候变化的？这个项目将使用大量但研究很少的植物来回答这些问题，这些植物只生长在美国和墨西哥奇瓦瓦沙漠富含石膏的土壤中。通过生成和分析大型DNA序列数据集，将重建和比较奇瓦瓦沙漠12个不同石膏限制植物群的详细进化历史。这一国际研究计划是了解一大批土壤受限植物物种的起源和进化多样性的第一次全面努力，因此将极大地提高我们对土壤如何影响植物进化以及土壤受限植物将如何应对持续的气候变化的理解。该项目还将提供一个新颖而引人入胜的框架，通过结合高中教师研讨会、文科大学创新的本科生生物实验室活动以及对学生研究人员的广泛指导，来提高高中生和大学生的进化素养。

This project integrates a vigorous research program to understand the evolution of plants restricted to unusual soils with an equally vigorous effort to improve high school and college student understanding of core concepts in evolutionary biology. Plant species that grow only on unusual soils, such as serpentine soils (high concentration of metals), bogs (low pH), or evaporites (high salinity), comprise a substantial proportion of plant biodiversity worldwide, but surprisingly little is known about their evolutionary history. For example, do plant lineages restricted to these unusual soils persist over long periods of evolutionary time? Likewise, how have such lineages responded to past climate changes? This project will answer such questions using a large but poorly studied group of plants that grow only in gypsum-rich soils within the Chihuahuan Desert of the US and Mexico. By generating and analyzing large DNA sequence data sets, the detailed evolutionary histories of 12 diverse gypsum-restricted plant groups in the Chihuahuan Desert will be reconstructed and compared. This international research program represents the first comprehensive effort to understand the origin and evolutionary diversification of a large, soil-restricted group of plant species, and consequently will vastly improve our understanding of how soils influence plant evolution and how soil-restricted plants will respond to ongoing climate change. This project will also provide a novel and engaging framework for improving evolutionary literacy in high school and college students, by employing a combination of high school teacher workshops, innovative undergraduate biology laboratory activities at a liberal arts college, and extensive mentoring of student researchers.