Paleoecology is the branch of ecology that studies the relationships between prehistoric living organisms and their environment, using fossils and prehistoric remains as evidences. The main objective of this discipline is to understand the various geological and biological cycles and interpret their interactions. This book provides significant information of this field to help develop a good understanding of marine and terrestrial environments, adaptation and preadaptation, paleoecological reconstructions, and related fields. It strives to provide a fair idea about this subject and to help gain a better insight into the latest advances within this field.