This title is back in print with a revised preface. "Microcosmos" brings together the remarkable discoveries of microbiology of the past two decades and the pioneering research of Dr. Margulis to create a vivid new picture of the world that is crucial to our understanding of the future of the planet. Addressed to general readers, the book provides a beautifully written view of evolution as a process based on interdependency and their interconnectedness of all life on the planet.