This book shares the diversity, beauty, and strangeness of ancient lakes, some millions of years old, and the insights they shine a light on about biodiversity. These lakes are home to a diverse array of fish, crustaceans, snails, and other creatures found nowhere else. Author Jeffrey McKinnon introduces this living diversity to the general reader and explains the surprising findings about the formation and persistence of species. The book provides an overview of their geological origins, evolutionary processes, the role of interspecies mating in rapid diversifications, the unique records of their inhabitants, and the prospects for the lakes in the Anthropocene. (This book may contain a sharpie mark on the top or bottom edge and may show mild signs of shelfwear.)