Size reductions during hyperthermal events: early warnings of environmental deterioration or signs of extinction? (EarlyWarn)

高温事件期间尺寸减小：环境恶化或灭绝迹象的早期预警？

• 批准号: 290428482
• 负责人: Professor Dr. Wolfgang Kießling, since 3/2022
• 金额: --
• 依托单位: Museum für Naturkunde - Leibniz-Institut für Evolutions- und Biodiversitätsforschung (MfN)
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/290428482?language=en
• 关键词: Size; reductions; during; hyperthermal; events

Size reductions in successive fossil assemblages during times of extinction are major features visible across a variety of temporal and spatial scales. The underlying environmental drivers and mechanisms are however still debated. In various cases, size responses predate the main extinction pulse suggesting that they might signal early environmental disruptions. The project proposed here aims to explicitly model size changes in a sequence stratigraphic framework to disentangle the local paleoenvironmental influences on these patterns from global ones. This approach will focus on within-facies and between-facies comparisons of mollusk and brachiopod assemblages of Permian-Triassic sections in Iran and various European Pliensbachian-Toarcian sections, hence covering a wide range of paleoenvironmental and preservational contexts before and across extinction events. These approaches are necessary to quantitatively disentangle the relative contribution of climate-related stressors and nutrient availability in driving patterns when filtering out potential collection and stratigraphy biases. The final part of the project will compare our newly collected high-resolution data with newly appended large size datasets considering appropriate facies, sequence stratigraphic and geochemical context to understand their relative contribution in the first comprehensive meta-analysis on these aspects of miniaturization (“Lilliput effect”). These datasets will also be used to disentangle the relative contribution of within-species size reductions, size-selective extinction/immigration and origination/immigration in driving size fluctuations during background conditions as well as during events ranging from minor biological crises to mass extinctions associated with hyperthermal events.

灭绝期间连续化石组合的尺寸减小是在各种时间和空间尺度上可见的主要特征。然而，潜在的环境驱动因素和机制仍然存在争议。在各种情况下，大小反应早于主要的灭绝脉冲，这表明它们可能预示着早期的环境破坏。这里提出的项目旨在明确地模拟层序地层框架中的尺寸变化，以将局部古环境对这些模式的影响与全球影响区分开来。该方法将重点关注伊朗二叠纪-三叠纪剖面和欧洲各个普林斯巴阶-托阿尔阶剖面的软体动物和腕足动物组合的相内和相间比较，从而涵盖灭绝事件之前和期间的广泛古环境和保护背景。在过滤潜在的收集和地层学偏差时，这些方法对于定量分析气候相关压力源和营养物质可用性在驱动模式中的相对贡献是必要的。该项目的最后部分将把我们新收集的高分辨率数据与新添加的大型数据集进行比较，考虑适当的相、层序地层和地球化学背景，以了解它们在小型化这些方面（“小人国效应”）的首次综合荟萃分析中的相对贡献。这些数据集还将用于理清物种内尺寸减小、尺寸选择性灭绝/移民和起源/移民在背景条件下以及从小型生物危机到与高温事件相关的大规模灭绝等事件期间驱动尺寸波动的相对贡献。