Book excerpt: Model Ecosystems in Extreme Environments, Second Edition examines ecosystems at the most extreme habitats and their interaction with the environment, providing a key element in our understanding of the role and function of microorganisms in nature. The book highlights current topics in the field, such as biodiversity and the structure of microbial communities in extreme environments, the effects of extreme environmental conditions on microbial ecosystems, and ecological and evolutionary interactions in extreme environments, among other topics. It will be a valuable text for faculty and students working with extremophiles and/or microbial ecology and researchers, including astrobiologists, biologists, evolutionary scientists, astronomers, geochemists and oceanographers. - Explores, in detail, how microbial ecosystems thrive in extreme environments - Highlights the relevance of extremophiles as model ecosystems to the study of microbial ecology - Examines how extreme ecosystems can help our search for life on other planets