Animals group together for a multitude of reasons, from safety in numbers to ease of finding prospective mates. These temporary or long-term associations of animals of the same species or colonies are explored in the latest entry in the Pods, Troops, and Other Animal Groups series (6 titles). After establishing the general elements of colony life, the book focuses on individual examples, from the more expected (penguins, sea lions, bees) to the more unusual (naked mole rats and the Portuguese man-of-war). Each spread features a rundown of basics (colony size, location), then offers more detailed information. Flashy text boxes, fun facts, and terrific photographs combine to great effect. Back matter includes a glossary, an index, and suggestions for learning more. An engaging and varied exploration of animal behavior.