Neoproterozoic paleobiology

新元古代(1000-5.42亿年前)是地球系统发生深刻变化的时代。地球物理和化学环境的大规模变化，包括超大陆的解体和一系列极端的全球冰河时代，与生命进化中同样根本性的变化同时发生。在接下来的五年里，我和我的学生将开展研究，研究地球上第一批动物和其他大型生物(以埃迪卡拉生物群为代表)的出现，以及碳酸盐系统向现代系统的演变，包括早期珊瑚礁。我的大部分研究工作将集中在埃迪卡拉生物群(5.78-5.42亿年前)。这些软体生物出现在新元古代冰河时代末期，标志着经过30亿年的主要微生物进化后，生命变大了，它们代表了世界上最古老的大型、复杂的生命形式。几乎所有的人都是完全柔软的身体，没有任何骨骼、肌肉、内脏或大脑的证据。一些埃迪卡拉物种可能是导致了所有现代动物生命的干群；另一些似乎代表了生命进化中的“失败实验”。我们的研究将集中在纽芬兰，那里包含了已知的最古老和一些保存最完好的埃迪卡拉组合。研究加拿大西北部的深水埃迪卡拉组合将有助于评估这些化石的全球特征。在纽芬兰和澳大利亚寻找低于主要化石水平的尚未发现的埃迪卡拉纪化石将测试冰川和氧气在大型动物进化中的作用。我还将研究加拿大西北部和澳大利亚的碳酸盐，这些碳酸盐沉积在两个最大的元古界冰期(约7.5亿-6.35亿年前)之间，以记录生物进化和全球气候变化对通过元古界碳酸盐系统发展的影响。这些研究将构成我的研究活动的核心，并将在未来五年为3名硕士学生、2名博士生、1名PDF和13名本科生现场助理提供支持和研究材料。

The Neoproterozoic (1000-542 million years ago) was an era of profound change in the Earth system. Large-scale changes in the physical and chemical environment of Earth, including break-up of a supercontinent and a series of extreme global ice ages, occurred in concert with equally fundamental changes in the evolution of life. Over the next five years my students and I will carry out research on the appearance of the first animals and other large creatures on Earth (as represented by the Ediacara Biota) and on the evolution of carbonate systems towards modern-style systems, including early reefs. Most of my research efforts will focus on the Ediacara Biota (578-542 million years ago). These soft-bodied creatures that appeared at the end of the Neoproterozoic ice ages mark "when life got big" after 3 billion years of mostly microbial evolution, and represent the oldest large, complex life forms anywhere. Almost all of them were entirely soft-bodied, without any evidence of skeletons, muscles, guts, or brains. Some Ediacaran forms may have been stem-groups that led to all modern animal life; others appear to represent "failed experiments" in the evolution of life. Our studies will focus on Newfoundland, which contains the oldest and some of the best preserved Ediacaran assemblages known anywhere. Investigating deep-water Ediacaran assemblages from NW Canada will help to assess the global character of the fossils. Searches for as yet undiscovered Ediacaran fossils below the main fossil levels in Newfoundland and Australia will test the roles of glaciation and oxygenation in the evolution of large animals I also will study carbonates from NW Canada and Australia that were deposited between the two greatest Proterozoic ice ages (Cryogenian, about 750-635 million years ago) to document the effects of biotic evolution and global climate change on the development of carbonate systems through the Proterozoic Eon. These studies will form the core of my research activities and will provide support and research materials for 3 MSc students, 2 PhD students, a PDF, and 13 undergraduate field assistants over the next five years.