CAREER: Polyploid phylogenetics and ploidy-aware taxonomy of Cystopteridaceae: Research and education from the field to museum collections

多倍体物种——拥有两套以上完整染色体的物种——在生命之树上很常见，尤其是在植物中。这些多倍体通常也是杂交种，它们不同的染色体组来自不同的亲本物种。这种“异源多倍体”是全球生物多样性的一个极其重要的组成部分，但对其长期进化（系统发育领域）的研究一直受到限制，因为异源多倍体具有网状而不是树状的进化史，因此系统发育分析的标准工具不适用。本研究将开发用于异源多倍体研究的系统发育工具，并证明这些工具在理解广泛分布的蕨类科（Cystopteridaceae）生物多样性的复杂模式及其产生过程中的有效性。结合这项研究，该项目将利用实地和基于收集的经验的力量，为每年从美国州立大学布兰丁分校（一所两年制大学）转到犹他州立大学洛根分校的土著学生提供变革的教育机会，包括创建一个相关的布兰丁四角植物标本室。这些教育活动有可能改变南加州大学洛根校区土著转学生的教育经历，进而对美国土著学生在STEM领域的代表性产生持久影响。为本科生和研究生提供指导研究经验的机会将与项目的研究活动相结合，并将提供山间植物标本馆探索计划，这将产生重要的生物多样性数据，并为公众提供野外植物学体验，同时将他们与当地环境联系起来。该项目将开发一个包含谱系出生、死亡和多倍体化过程的系统发育树模型，这将允许多倍体网状进化史的生物学信息推断和多倍体多样化相关假设的测试。本文将从大约1500个样本的多位点数据集中推断出蕨科多倍体物种网络，这将为多倍体宏观进化的“死角”假说提供第一个主要的、集中的经验检验。最后，在线修订专著展示了“倍性意识”的修订系统学和动态在线电子专著的潜力，将为广大公众提供重要的资源。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Polyploid species—species with more than the two complete sets of chromosomes—are common across the tree of life, especially in plants. These polyploids are often also hybrids, with their different chromosome sets coming from different parent species. Such “allopolyploids” are a tremendously important component of global biodiversity, but study of their long-term evolution (the field of phylogenetics) has been limited because allopolyploids have a web-like rather than tree-like evolutionary history and thus standard tools for phylogenetic analysis do not apply. This research will develop phylogenetic tools for the study of allopolyploids and demonstrate the effectiveness of these tools for understanding complex patterns of biodiversity and the processes that generated them in the widespread fern family, Cystopteridaceae. In conjunction with this research, the project will leverage the power of field- and collections-based experiences to provide transformative educational opportunities for an annual cohort of Indigenous students transferring to Utah State University (USU) Logan from USU Blanding (a two-year institution), including the creation of an associated Blanding Four Corners Herbarium. These educational activities have the potential to transform the educational experience of Indigenous transfer students at the USU Logan campus, and by extension, to make a lasting impact on the representation of Native American students in STEM fields. Opportunities for mentored research experiences for undergraduate and graduate students will be integrated with the project’s research activities, and an Intermountain Herbarium Foray Program will be offered, which will generate important biodiversity data and provide field botany experiences to the public while connecting them with the local environment. This project will develop a phylogenetic tree model that incorporates the processes of lineage birth, death, and polyploidization, which will allow for the biologically-informed inference of the reticulate evolutionary history of polyploids and testing of hypotheses related to polyploid diversification. A densely sampled polyploid species network for the fern family Cystopteridaceae will be inferred from a multi-locus dataset of approximately 1500 accessions, which will provide the first major, focused empirical test of the “dead-end” hypothesis of polyploid macroevolution. Finally, an online revisionary monograph showcasing “ploidy-aware” revisionary systematics and the potential of dynamic online e-monography will provide a critical resource for members of the broader public.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.