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