Hoff, Mary King

Discusses how various animals and plants use special tools or techniques to protect themselves, such as the turtle's hard shell, the stinging nettles' hairs, and the pufferfish's ability to expand.

Investigates the creatures that sleep during the day and work at night, looking particularly at adaptations, such as flashing lights or powerful scents, which help them to survive.

Alerts the reader to the dangers of surface water pollution and the global imperative to keep these waters fresh.

Describes concisely the global uses and abuses of the world's oceans and seas.

Describes the global uses and abuses of groundwater and suggests ways to preserve this valuable resource.

Presents an introduction to monkeys, in simple text with illustrations, describing their physical characteristics, habitat, behavior, and more.

An examination of the earth's atmosphere and the factors which threaten its stability, such as ozone loss and global warming.

Discusses animal migration, including different animals that migrate, the routes they take and how they navigate, and the various reasons that they make the journey.