An introduction to motion that explains what motion is, how it works, and how it is created in everyday life and provides simple experiments to help readers understand the scientific concepts presented.
Presents facts on the American mink; explains how they became an invasive species in several parts of the world, taking over territory outside their native habitats; describes the ecological problems this has caused; and discusses solutions.
Describes the physical characteristics and behaviors of starlings, explores the threats they pose to native birds of North America, and discuss possible solutions to their invasiveness.
Explains what zebra mussels are, how they form, and how and where they live, looks at how zebra mussels spread beyond their native habitats, and discusses the problems caused by invading zebra mussels and what is being done to control the spread.
Introduces students to the gray whale, describing its habitat, behavior, and threats to its existence, and explores how people are trying to save it from extinction.
Describes the characteristics, behaviors, and life cycles of American alligators, explains how hunting and habitat destruction led the species to the brink of extinction, and discusses how legislation led to the recovery of American alligator populations and some of the problems caused by too many alligators.
Describes the feeding habits, migratory patterns, physical characteristics, and habitat of the endangered whooping crane, including efforts to save them, such as the establishment of the Arkansas National Wildlife Refuge.
Presents a concise study of the Megatherium, a giant prehistoric sloth originally believed to have inhabited parts of North, Central, and South America.
