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，包括超大陆的分裂和一系列极端的全球冰河时代，都与生命进化中同样根本的变化相一致。 在接下来的五年里，我和我的学生将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，包括早期的珊瑚礁。 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）。 这些出现在新元古代冰河时代末期的软体生物，标志着经过30亿年的微生物进化后，“生命变得庞大”，并代表了任何地方最古老的大型复杂生命形式。 它们几乎都是软体动物，没有任何骨骼、肌肉、内脏和大脑的迹象。 埃迪卡拉纪的一些形式可能是导致所有现代动物生命的茎群;其他形式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，那里有最古老和保存最完好的埃迪卡拉组合。 调查来自加拿大西北部的深水埃迪卡拉组合将有助于评估化石的全球特征。 在纽芬兰和澳大利亚的主要化石层之下寻找尚未发现的埃迪卡拉化石，将测试冰川作用和氧化作用在大型动物进化中的作用。 我还将研究来自加拿大西北部和澳大利亚的碳酸盐，这些碳酸盐是在两个最大的元古宙冰河时代（Cryogenian，大约7.5亿至6.35亿年前）之间沉积的，以记录生物进化和全球气候变化对元古宙碳酸盐系统发展的影响。 这些研究将形成我的研究活动的核心，并将在未来五年内为3名硕士生，2名博士生，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.