In this text, readers can attend to the precise details of explanations and descriptions as expressed in the Reading Standards for Literacy in Science and Technical Subjects. They learn about animal diversity and investigate feeding differences. Animal locomotion, habitats, methods animals use to defend themselves, reproduction, and animal associations and symbioses (such as mutualisms, commensalism, and parasitisms) are explored in depth.

Diversity in the animal kingdom -- Ways of eating -- Locomotion -- Adapting to habitats -- Animal defense mechanisms -- Mating and offspring -- Close associations among animals -- Animal systems of communication -- Biography: Charles Darwin.