DISSERTATION RESEARCH: The Consequences of Global Events on Vertebrate Biodiversity: the Paleozoic Actinopterygian Radiation

大规模物种灭绝等全球性事件对生物多样性产生了持久的影响：放射线鳍类动物是目前数量最多、种类最多的脊椎动物；然而，这种情况只有在先前的优势种群与古生代汉根堡大灭绝事件同时遭受重大损失之后才会出现。本项目将研究：(1)与气候变化相关的汉根堡灭绝事件是否永久性地重构了全球脊椎动物的生物多样性；(2)光翅目动物在经历灭绝瓶颈期后经历了大规模辐射；(3)在灭绝后生态系统中，放线鱼的多样化是对生态位空缺的响应，导致了新的功能形态的广泛进化。该项目将建立全面的脊椎动物发生数据库，重建新的系统发育系统，分析脊椎动物形态空间的占用/再占用。研究放光鳍鱼的进化对于解释当前脊椎动物的生物多样性至关重要，因为这些鱼类是现代生态系统的主要组成部分。系统发育、形态和多样性数据将被放置在开放的数据库中，为脊椎动物宏观进化的进一步研究提供起点。由于古生物学具有广泛的吸引力，其研究结果对于设计科学课程和其他易于理解的项目将是有价值的——向普通公众灌输更广泛的概念，包括进化、生物多样性的丧失和更替，以及大规模的全球变化。

Global events such as mass extinctions have lasting impacts on biodiversity: Actinopterygians (ray-finned fishes) are currently the most abundant and diverse group of living vertebrates; however, this situation only arose after previously dominant groups suffered major losses coincident with the Paleozoic Hangenberg mass extinction event. This project will examine whether: (1) the Hangenberg extinction event, associated with climatic changes, permanently restructured global vertebrate biodiversity; (2) actinopterygians underwent a large-scale radiation after an extinction bottleneck; (3) actinopterygian diversification occurred in response to vacated niches in post-extinction ecosystems, leading to the widespread evolution of novel functional morphologies. This project will assemble comprehensive vertebrate occurrence databases, reconstruct new phylogenies, and analyze the occupation/reoccupation of vertebrate morphospace. Investigation of actinopterygian evolution is vital for interpreting current vertebrate biodiversity because these fishes are a major component of modern ecosystems. Phylogenetic, morphological, and diversity data will be placed in open repositories, providing starting points for further studies of vertebrate macroevolution. The results will be valuable for designing science curricula and other accessible programs because of paleontology's broad appeal - instilling in the general public an appreciation for broader concepts including evolution, biodiversity loss and turnover, and large-scale global change.