From high latitudes into the tropics: The role of palaeogeography for the biodiversification of Ordovician bryozoans of Baltoscandia

从高纬度到热带：古地理对巴尔托斯坎迪亚奥陶纪苔藓虫生物多样性的作用

• 批准号: 413010093
• 负责人: Privatdozent Dr. Andrej Ernst, Ph.D.
• 金额: --
• 依托单位: Institut für Geologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/413010093?language=en
• 关键词: latitudes; into; tropics; role; palaeogeography

This proposal intends study of patterns of the spatial diversity of the Ordovician bryozoans of Baltoscandia. After the Cambrian explosion, the Great Biodiversification Event (GOBE) was the second pulse of diversification of the life in the Phanerozoic. The intended study will help to reveal new insights in the processes of biodiversification during the GOBE.The central aim of the project is to identify the role of spatial diversity in the diversification. This study will answer the questions, at which level the biodiversification takes place, which ecological parameters drive it, and how strong is the influence of provinciality and migrations on the biodiversification. Bryozoans are a perfect model group for study of diversity patterns in the Ordovician because they have many advantages including possessing of calcified skeleton in the majority of clades, their modular organisation (strictly colonial), wide distribution in marine biotopes of the Ordovician. They occupied the shelves of Baltica, a palaeocontinent moved from high latitudes towards the tropics during the Ordovician. This drift resulted in a gradual climatic change which certainly affected the diversity dynamics of the benthic fauna, among them bryozoans. The combination of the fast biodiversification of bryozoans and the palaeogeographical shift of Baltica is the beneficial condition to study the temporal and spatial diversity patterns. The study of diversity (alpha-, beta-, gamma-) will be concentrated in two temporal/spatial transects: 1) Darriwilian of Norway, Sweden, Estonia, and NW Russia, and 2) Katian of Norway, Sweden, Estonia, and NW Russia. In addition, palaeobiogeographic patterns of Ordovician bryozoan faunas of Baltoscandia will be studied, in order to estimate the role for migrations in biodiversification processes. In the course of the intended study several hypotheses will be tested. Firstly, it is supposed that biodiversification was strong at the local scale, and isolation played an important role. Secondly, certain ecological factors as substrate type, depth, sediment influx, and probably nutrient support influenced the biodiversification of bryozoans in the Ordovician. Thirdly, large-scaled migration apparently suppressed the biodiversification resulting in the increase of the alpha-diversity (local) but decrease of the beta-diversity (interregional), whereas gamma-diversity (regional) remains without changes. It is expected that the all components of diversity increase during biodiversification events, whereas during mass extinctions separate parts of the global diversity (alpha-, beta-, or gamma-) are affected.

该提案旨在研究巴尔托斯坎迪亚奥陶纪苔藓虫的空间多样性模式。寒武纪大爆发之后的生物多样性大事件（GOBE）是显生宙生命多样化的第二次脉冲。预期的研究将有助于揭示 GOBE 期间生物多样化过程的新见解。该项目的中心目标是确定空间多样性在多样化中的作用。这项研究将回答以下问题：生物多样性发生在哪个水平，哪些生态参数驱动它，以及省级和移民对生物多样性的影响有多大。苔藓动物是研究奥陶纪多样性模式的完美模型类群，因为它们具有许多优点，包括大多数进化支具有钙化骨骼、其模块化组织（严格的群体性）、在奥陶纪海洋生物生境中的广泛分布。他们占据了波罗的海大陆架，这是奥陶纪期间从高纬度地区向热带地区移动的古大陆。这种漂移导致了逐渐的气候变化，这无疑影响了底栖动物群的多样性动态，其中包括苔藓虫。苔藓虫快速生物多样性与波罗的海古地理变化的结合为研究时空多样性格局提供了有利条件。多样性（α、β、γ）的研究将集中在两个时间/空间横断面：1）挪威、瑞典、爱沙尼亚和俄罗斯西北部的 Darriwilian，以及 2）挪威、瑞典、爱沙尼亚的 Katian俄罗斯西北部。此外，还将研究巴尔托斯坎迪亚奥陶纪苔藓虫动物群的古生物地理模式，以估计迁徙在生物多样性过程中的作用。在预期研究的过程中，将测试几个假设。首先，假设局部范围内生物多样性很强，隔离发挥了重要作用。其次，某些生态因素，如基质类型、深度、沉积物流入，以及可能的营养支持，影响了奥陶纪苔藓虫的生物多样性。第三，大规模迁移明显抑制了生物多样性，导致α多样性（局部）增加，但β多样性（区域间）减少，而γ多样性（区域）保持不变。预计生物多样性事件期间多样性的所有组成部分都会增加，而在大规模灭绝期间，全球多样性的各个部分（α、β或γ）都会受到影响。