Resolving the enigmatic Precambrian-Cambrian boundary event (BACE)

解决神秘的前寒武纪-寒武纪边界事件（BACE）

• 批准号: NE/T008458/1
• 负责人: Rachel Wood
• 金额: $ 78.34万
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FT008458%2F1
• 关键词: Resolving; enigmatic; Precambrian; Cambrian; boundary

Charles Darwin's 'great dilemma' was why complex life in the form of fossil animals seemed to appear so abruptly in rocks around 540 million years ago (Ma), in what is widely known as the Cambrian Explosion. Although we now know that many fossils are found in slightly older rocks, nonetheless the triggers and drivers of the Cambrian Explosion remain highly enigmatic. This revolutionary event follows immediately after a perturbation in the carbon cycle as revealed by carbon isotopes. This is known as the BAsal Cambrian carbon isotope Excursion (the BACE), and although has long been known, this event remains highly enigmatic. This is because there is no single stratigraphic section that allows us to create an integrated picture, which needs to include where and at what time the key fossils are found, the geochemistry that can tell us about how the Earth's environment may have changed at this time, and finally absolute ages (dates) of the rocks so that we can reconstruct the exact order of events. This means that our understanding of this profound evolutionary transition remains very uncertain.In this project we will use unique and new archives of sedimentary rocks derived from drilled, subsurface cores. This enables us to construct a much higher resolution, four-dimensional (temporal-spatial) picture of the evolutionary history of the earliest animals and their environment. These cores are from three diverse locations: Namibia, Brazil and South China, so that we can compare local to global patterns. Such cores are unweathered, so will preserve the most accurate geochemical signatures possible. We have also assembled a very multidisciplinary team, which combines complementary expertise in: 1) geochronology - the dating of rocks; 2) geochemistry - for reconstructing nutrient and biogeochemical cycles; 3) palaeontology - the record of life and evolution; and 4) mathematical modelling, which will enable us to capture geological information, in such a way as to test key hypotheses about the effects of animal evolution on environmental stability. Our project aims to address three central scientific questions: Q1: Is the BACE local or global, diagenetic or primary? Q2: What were the causes of the BACE? and Q3: What role did the BACE play in the evolution of metazoans? We will consider environmental factors, such as changes in oxygen levels, as the drivers of evolutionary change. By distinguishing physical, extrinsic drivers we can address a fundamental and motivating question: what caused animals to evolve and radiate when they did? This unique dataset is likely to be transformative as it will resolve the key processes fundamental to the coupled evolution of the Earth System and the rise of complex life.This study has relevance to today's biosphere, as the modern Earth system and its stabilising feedbacks arose during this key interval. By studying it in more detail, and establishing temporal relationships and causality between key events, we can find out how the modern Earth system and the unique life it carries, is structured.

查尔斯·达尔文（Charles Darwin）的“巨大困境”就是为什么以化石动物形式的复杂生活在大约5.4亿年前（MA）中突然出现在岩石中，这被称为寒武纪爆炸。尽管我们现在知道在稍旧的岩石中发现了许多化石，但是坎布里亚爆炸的触发因素和驱动因素仍然是高度神秘的。碳同位素揭示的碳循环扰动后，这一革命性事件立即发生。这被称为基础寒武纪同位素偏移（贝斯），尽管长期以来已知，但该事件仍然是高度神秘的。这是因为没有单个地层部分使我们能够创建一个集成的图片，其中需要包括在哪里和什么时候找到关键化石，可以告诉我们此时地球环境可能发生的地球化学，最后是岩石的绝对年龄（日期），以便我们可以重建事件的确切顺序。这意味着我们对这种深刻的进化过渡的理解仍然非常不确定。在这个项目中，我们将使用源自钻孔的地下岩心的独特而新的沉积岩石档案。这使我们能够构建最早的动物及其环境进化史的更高分辨率，四维（时间空间）的图片。这些核心来自三个不同的地点：纳米比亚，巴西和中国南部，因此我们可以将本地模式与全球模式进行比较。这样的核心是不受欢迎的，因此将保留最准确的地球化学特征。我们还组建了一个非常多学科的团队，该团队结合了以下方面的补充专业知识：1）年代学 - 岩石的约会； 2）地球化学 - 用于重建营养和生物地球化学周期； 3）古生物学 - 生活和进化的记录； 4）数学建模将使我们能够捕获地质信息，以检验有关动物进化对环境稳定性影响的关键假设。我们的项目旨在解决三个中心科学问题：Q1：BACE本地还是全球，成岩化还是主要的？ Q2：裁剪的原因是什么？和Q3：贝丝在后生动物的演变中起着什么作用？我们将将环境因素（例如氧气水平的变化）视为进化变化的驱动因素。通过区分身体的外部驱动因素，我们可以解决一个基本和激励的问题：是什么导致动物在做到的时候进化和辐射？这个独特的数据集可能会具有变革性，因为它将解决与地球系统耦合进化和复杂寿命兴起的基础的关键过程。这项研究与当今的生物圈相关，因为现代地球系统及其在此关键间隔内就产生了现代地球系统及其稳定反馈。通过更详细地研究它，建立关键事件之间的时间关系和因果关系，我们可以找出现代地球系统和它所携带的独特生活的结构。

项目成果

Enhanced clay formation key in sustaining the Middle Eocene Climatic Optimum.

• DOI: 10.1038/s41561-023-01234-y
• 发表时间: 2023
• 期刊: NATURE GEOSCIENCE
• 影响因子: 18.3
• 作者: Krause, Alexander J. J.;Sluijs, Appy;van der Ploeg, Robin;Lenton, Timothy M.;von Strandmann, Philip A. E. Pogge
• 通讯作者: von Strandmann, Philip A. E. Pogge

Constraining the onset and environmental setting of metazoan biomineralization: The Ediacaran Nama Group of the Tsaus Mountains, Namibia

• DOI: 10.1016/j.epsl.2023.118336
• 发表时间: 2023-08-17
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: Bowyer, Fred T.;Uahengo, Collen-Issia;Wood, Rachel A.
• 通讯作者: Wood, Rachel A.

Modelling Ediacaran metazoan-microbial reef growth

模拟埃迪卡拉后生动物-微生物礁的生长

• DOI: 10.1111/sed.12832
• 发表时间: 2020
• 期刊: Sedimentology
• 影响因子: 3.5
• 作者: Curtis A

Implications of an integrated late Ediacaran to early Cambrian stratigraphy of the Siberian Platform, Russia

• DOI: 10.1130/b36534.1
• 发表时间: 2023-09-01
• 期刊: GEOLOGICAL SOCIETY OF AMERICA BULLETIN
• 影响因子: 4.9
• 作者: Bowyer, Fred T.;Zhuravlev, Andrey Yu;Zhu, Maoyan
• 通讯作者: Zhu, Maoyan

Insights Into the Terminal Ediacaran Marine Carbonate Record From Shale-Hosted Carbonate Carbon Isotopes

• DOI: 10.2475/001c.88082
• 发表时间: 2023-11
• 期刊: American Journal of Science
• 影响因子: 2.9
• 作者: F. Bowyer;Mariana Yilales;Rachel Wood;S. Poulton