Land-dwelling mammals can to walk, run and jump. Salamanders, turtles and lizards also walk, but are often said to crawl. Termites and ants are among the many insects that walk a great deal too. Grasshoppers and crickets jump, but they also walk about slowly when they are eating. Even flying birds must be able to walk or hop on land. The garden snail produces a watery liquid that serves as a private lake. This snail rolls through this lake by contracting muscles that move its skin. This is also another form of animal movement on land.

Many animals live in the ground and must get from place to place. Moles and other burrowing animals dig their way through the earth rapidly with shovel-like legs. Earthworms often eat their way through. When the soil is loose, they push through it in the same way that they move on the surface of the ground. A worm also moves about by digging into the ground and making itself longer and then shorter. In this way it pulls itself ahead.

Several other animals fly through the air to transport themselves. Others, like flying squirrels, flying frogs, flying fish and flying lizards do not really fly but instead glide through the air. The best gliders are the flying fish that leap from the water with such force that they can glide as far as 50 yards.

A true flying animal has the ability to propel itself through the air by beating its wings against the air. Only four groups of animals have produced species that can truly fly: they are the bats, the birds, the insects and the flying reptiles that died out with the dinosaurs. Each group has its own kind of wing design and aerodynamics. However, the wings of bats, birds and flying reptiles are alike in having bones. An insect's wing, like an insect's body, has no bones at all. The veins that strengthen its wing are really air tubes with strong walls.

A great many animals also live in the water, primarily because there is much more room for them than on land. Mammals, such as dolphins and whales, live only in the water. Many birds do a great deal of paddling about in the water. Reptiles, like turtles and amphibian animals, like frogs, can also live half their lives in a body of water. But most of the swimming animals belong to the class of fishes. The movement of a fish's tail fin helps propel a fish through the water. Yet many fish can still swim even if most of the tail fin is a bitten or cut off. They can push themselves through the water by twisting their bodies from side to side. Some fish can also move forward or backward by means of their side fins. Other animals move through the water by jet propulsion. Squids and cuttlefish suck water into their bodies and then squirt it out. This shoots them forward. Jellyfish also swim by jet propulsion. They open their jelly umbrellas and then rapidly close them. When the stream of water gets out, the jellyfish is pushed forward. Many tiny animals row themselves through water. They have tiny hairs called cilia which act as oars. Other tiny creatures have whiplike threads with which they pull themselves forward.

There are still more curious ways in which animals move. Some ride from place to place on other animals, like the remora fish. It fastens itself onto sharks or other big fish so that when the sharks kill another fish, the remora frees itself to go after a part of the meal.