Neoproterozoic paleobiology

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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.