Neoproterozoic Geobiology and Paleobiology

The Neoproterozoic Era (1000¿542 million years ago) is a geological period of dramatic climatic change and important evolutionary innovations. Repeated glaciations of unusual magnitude occurred throughout this tumultuous interval, and various eukaryotic clades independently achieved multicellularity, becoming more complex, abundant, and diverse at its termination. Animals made their first debut in the Neoproterozoic too. The intricate interaction among these geological and biological events is a centrepiece of Earth system history, and has been the focus of geobiological investigations in recent decades. The purpose of this volume is to present a sample of views and visions among some of the growing numbers of Neoproterozoic workers. The contributions represent a cross section of recent insights into the field of Neoproterozoic geobiology. Chapter One by Porter gives an up-- date review of Proterozoic heterotrophic eukaryotes, including fungi and various protists. Heterotrophs are key players in Phanerozoic ecosystems; indeed, most Phanerozoic paleontologists work on fossil heterotrophs. However, the fossil record of Proterozoic heterotrophs is extremely meagre.

Chapter 1: The Proterozoic Fossil Record of Heterotrophic Eukaryotes Sussannah M. Porter 1. Introduction 2. Eukaryotic Tree 3. Fossil Evidence for Proterozoic Heterotrophs 4. Why Are Heterotrophs Rare in Proterozoic Rocks? 5. Conclusions Chapter 2: On the Morphological History of Proterozoic and Cambrian Acritarchs John Warren Huntley, Shuhai Xiao, and Michael Kowalewski 1. Introduction 2. Materials and Methods 3. Results 4. Discussion 5. Conclusions Acknowledgments References Appendix: SAS/IML Codes Chapter 3: On the Morphological and Ecological History of Proterozoic Macroalgae Shuhai Xiao and Lin Dong 1. Introduction 2. A Synopsis of Proterozoic Macroalgal fossils 3. Morphological History of Proterozoic Macroalgae 4. Discussion 5. Conclusions Acknowledgments References Chapter 4: Evolutionary Paleoecology of Ediacaran Benthic Marine Animals David J. Bottjer and Matthew E. Clapham 1. Introduction 2. A Mat-Based World 3. Nature of the Data 4. Evolutionary Paleoecology 5. Discussion Acknowledgements References Chapter 5: A Critical Look at the Ediacaran Trace Fossil Record Sören Jensen, Mary L. Droser and James G. Gehling 1. Introduction 2. Problems in the Interpretation of Ediacaran Trace Fossils 3. List of Ediacaran Trace Fossils 4. Discussion Acknowledgments References Chapter 6: The Developmental Origins of Animal Bodyplans Douglas H. Erwin 1. Introduction 2. Pre-Bilaterian Developmental Evolution 3.Development of the Urbilateria 4. Constructing Ancestors 5. Conclusions Acknowledgments References Chapter 7: Molecular Timescale of Evolution in the Proterozoic S. Blair Hedges, Fabia U. Battistuzzi, Jaime E. Blair 1. Introduction 2. Molecular Clock Methods 3. Molecular Timescales 4. Astrobiological Implications 5. Conclusions Acknowledgments References Chapter 8: A Neoproterozoic Chronology Galen P. Halverson 1. Introduction 2. Constructing the Record 3. Review of the Neoproterozoic 4. Conclusions Acknowledgments References Chapter 9: On Neoproterozoic Cap Carbonates as Chronostratigraphic Markers Frank A. Corsetti and Nathaniel J. Lorentz 1. Introduction 2. Key Neoproterozoic Successions 3. Discussion 4. Conclusion References