A can of worms-tracing the origins of Ecdysozoa using fossils, molecules and morphology in a Bayesian framework

一罐蠕虫——在贝叶斯框架中利用化石、分子和形态追踪蜕皮动物的起源

• 批准号: 2821208
• 金额: --
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2821208
• 关键词: worms; tracing; origins; Ecdysozoa; using

Project Background Ecdysozoans comprise some of the most successful invertebrate phyla, such as the arthropods and nematodes. However, other members of the group are less abundant today than they used to be. An amazing fossil record with a focus on newly collected material from the Early Cambrian Sirius Passet may provide means to better understand the nature of the ancestral ecdysozoan and how these many different fossil worms are related to their extant counterparts. It has been debated whether many of these vermiform fossils are subtending various branches of the tree or mainly the group that they resemble the most, the priapulids. This project will seek to integrate fossils, morphology and molecular sequence data to investigate the phylogeny and evolution of the Ecdysozoa. Project Aims and Methods Many new fossils have been discovered in the remote Sirius Passet in North Greenland. These new fossils feature unseen characters that may be useful in better understanding the nature of palaeoscolecid worms and their affiliation to living groups. Using these fossils as a template, we will explore the fossil record from different sites and compile their anatomy with modern forms to explore their phylogenetic placement. Furthermore, we will explore the use of combined morphology, molecules and fossils with stratigraphic ages to co-estimate phylogeny and divergence times which may help reveal incidences of convergent evolution that can result in erroneous placements of fossil taxa. Within the framework of thinking about Ecdysozoan evolution there are several levels of freedom within the student can explore different subject and take the project in new directions. These can range from exploration and description of new taxa, developing methods for visualization and reconstruction of fossils, development of phylogenetic methods or testing methods on other groups of organisms to compare and contrast with. A student with a personal perspective on how the project could evolve and develop is much welcomed. Project partners The project features supervisors from Bristol, Bath, The Natural History Museum and KOPRI. All have expertises on the group of animals and the methods used. These supervisors provide for a wealth of intellectual and experiential resource for discussion of findings and mentorship to the candidate. The proximity of Bath and the Natural History museum means that the student will be able to regularly meet these supervisors in person and the British team can easily gather for one day events to discuss the project. The supervisors at KOPRI may visit England for such gatherings, but the student and the lead supervisor will regularly visit South Korea to work on fossil material held in their collections. The Natural History Museum holds collections of extant material along with fossil specimens that may provide for useful comparisons and study when compiling the anatomical matrix for phylogenetic analysis. Training The student will be spending time investigating these fossils and learning how to interpret the fossils and reveal as much anatomy as possible using imaging techniques, camera lucida drawings and elemental mapping. Furthermore, the student will become proficient in using R and Linux shell interface for command-prompting. The student will travel to South Korea for some extended periods to work on material held there. Museum visits to study collections from other localities is also recommended.

项目背景 蜕皮动物包括一些最成功的无脊椎动物门，例如节肢动物和线虫。然而，该群体的其他成员今天的数量不如以前。一份令人惊叹的化石记录，重点是从早寒武世天狼星帕塞特新收集到的材料，这可能为更好地了解祖先蜕皮动物的性质以及这些许多不同的化石蠕虫与它们现存的对应物之间的关系提供了手段。人们一直争论这些蠕虫状化石中是否有许多蠕虫状化石位于树的各个分支上，或者主要是与它们最相似的群体，即前虫类。该项目将寻求整合化石、形态和分子序列数据来研究蜕皮动物的系统发育和进化。项目目标和方法 在格陵兰岛北部偏远的天狼星帕塞特地区发现了许多新化石。这些新化石具有看不见的特征，可能有助于更好地了解古头虫的性质及其与现存群体的关系。以这些化石为模板，我们将探索不同地点的化石记录，并用现代形式汇编它们的解剖结构，以探索它们的系统发育位置。此外，我们将探索使用组合形态、分子和化石与地层年龄来共同估计系统发育和分歧时间，这可能有助于揭示可能导致化石类群错误放置的趋同进化的发生率。在思考蜕皮动物进化的框架内，学生可以有多个层次的自由，可以探索不同的主题并将项目推向新的方向。这些范围包括新分类群的探索和描述、开发化石可视化和重建的方法、开发系统发育方法或对其他生物体进行比较和对比的测试方法。非常欢迎对项目如何发展和发展有个人看法的学生。项目合作伙伴 该项目由来自布里斯托尔、巴斯、自然历史博物馆和 KOPRI 的主管负责。所有人都拥有动物群体和所用方法的专业知识。这些主管提供了丰富的知识和经验资源，用于讨论研究结果和对候选人进行指导。巴斯和自然历史博物馆邻近意味着学生将能够定期亲自与这些导师会面，并且英国团队可以轻松地聚​​集在一起举行一日活动来讨论该项目。 KOPRI 的主管可能会访问英国参加此类聚会，但学生和首席主管将定期访问韩国，研究他们收藏中的化石材料。自然历史博物馆收藏了现存材料和化石标本，在编制系统发育分析的解剖矩阵时，可以提供有用的比较和研究。培训 学生将花时间研究这些化石，学习如何解释化石，并使用成像技术、相机清晰绘图和元素测绘尽可能多地揭示解剖结构。此外，学生将熟练使用 R 和 Linux shell 界面进行命令提示。该学生将前往韩国一段较长时间，研究那里的材料。还建议参观博物馆，研究其他地区的藏品。