Phylogenetic Relationships and Evolutionary History of the Freshwater, Apical Pore Field-Bearing Cymbelloid and Gomphonemoid Diatoms

硅藻是浮游藻类，其硅质骨架是 常见于海洋和淡水化石记录中。 首席研究员尤金斯托默建议继续他的 研究淡水硅藻的进化起源， 现存物种之间的祖先-后代关系 钹状和喇叭状硅藻。 光学显微镜和扫描电子 显微镜将用于研究超微结构，细胞学和 瓣膜形态 分支系统学方法将用于重建 生物群体的进化关系，这将是 与它们在化石中出现的顺序相比 记录 拟议中的工作所涉及的问题超出了 硅藻分类学 硅藻被广泛用作环境 湖泊的指标，拟议的工作将改善其 分类和识别标准。 更好的 了解硅藻进化的克里思和模式， 出现，该项目将作为其他模式 研究人员试图对现代和 化石物种

Diatoms are planktonic algae whose siliceous skeletons are commonly found in the marine and freshwater fossil record. Principal Investigator Eugene Stoermer proposes to continue his research into the evolutionary origins of freshwater diatoms, and the ancestor-descendant relationships among living species of the cymbelloid and gomphonemod diatoms. Light and scanning electron microscopy will be used to study ultrastructure, cytology and valve morphology. Cladistic methods will be used to reconstruct evolutionary relationships of living groups, which will then be compared with the sequence of their appearances in the fossil record. The proposed work has implications beyond the discipline of diatom systematics. Diatoms are widely used as environmental indicators in lakes, and the proposed work will improve their classification and identification criteria. A better understanding of the tempo and mode of diatom evolution will emerge, and the project will serve as a model for other researchers attempting to do integrated research on modern and fossil species.