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.

蜕皮动物包括一些最成功的无脊椎动物门，如节肢动物和线虫。然而，该集团的其他成员今天比以前少了。一个惊人的化石记录，重点是从早寒武世天狼星帕塞特新收集的材料，可以提供更好地了解祖先蜕皮动物的性质，以及这些不同的化石蠕虫是如何与现存的对应物。一直有争议的是，这些蠕虫状化石中的许多是对着树的各个分支，还是主要是它们最相似的群体，即灵长目。本计画将整合化石、形态及分子序列资料，以探讨蜕皮动物的发生与演化。项目目标和方法在格陵兰北部偏远的天狼星帕塞特发现了许多新的化石。这些新化石具有看不见的特征，可能有助于更好地了解古蠕虫的性质及其与生活群体的联系。以这些化石为模板，我们将探索不同地点的化石记录，并将它们的解剖与现代形式结合起来，以探索它们的系统发育位置。此外，我们将探索使用相结合的形态，分子和化石与地层年龄共同估计的进化和分歧的时间，这可能有助于揭示收敛进化的发生率，可能会导致错误的化石分类群的位置。在思考蜕皮动物进化的框架内，学生可以探索不同的主题并将项目带到新的方向。这些方法包括探索和描述新的分类群，开发可视化和重建化石的方法，开发系统发育方法或其他生物群的测试方法以进行比较和对比。一个学生与个人的观点如何项目可以演变和发展是非常欢迎的。项目合作伙伴该项目的负责人来自布里斯托、巴斯、自然历史博物馆和KOPRI。所有人都对动物群和使用的方法有专业知识。这些主管提供了丰富的知识和经验资源，用于讨论调查结果和指导候选人。巴斯和自然历史博物馆的邻近意味着学生将能够定期亲自会见这些主管，英国团队可以轻松地聚集一天的活动来讨论该项目。KOPRI的主管可能会访问英国参加这样的聚会，但学生和首席主管将定期访问韩国，研究他们收藏的化石材料。自然历史博物馆收藏了沿着的现存材料和化石标本，在编制系统发育分析的解剖学矩阵时，这些标本可以提供有用的比较和研究。培训学生将花时间调查这些化石，并学习如何解释化石，并使用成像技术，相机清晰度绘图和元素映射尽可能多地揭示解剖结构。此外，学生将熟练使用R和Linux shell接口进行命令提示。该学生将前往韩国进行一段时间的工作，在那里举行的材料。还建议参观博物馆，研究其他地方的收藏品。