Amphibians are born in water and breathe through gills but develop lungs on land. Birds have feathers, lay eggs, and have wings that allow most but not all to fly. Fish live in water and have gills, scales and fins. Arthropods include insects, spiders and crustaceans which have more than four jointed legs. Mammals are warm-blooded animals that bear live young and produce milk to feed their young. Reptiles are cold-blooded with scaly skin and include snakes, lizards, crocodiles and turtles.

1. Animal Classification

2. Amphibians Amphibians are born in the water. When they are born, they breathe with gills like a fish. But when they grow up, they develop lungs and can live on land. Frogs, toads and salamanders are amphibians.

3. Birds Birds are animals that have feathers and that are born out of hard-shelled eggs. All birds have feathers and birds are the only animals that do. The feathers on a bird’s wings and tail overlap. Because they overlap, the feathers catch and hold the air. This helps the bird to fly, steer itself and land. Although it's true that all birds have feathers and wings, that doesn't necessarily mean they can all fly. A penguin spends as much as 75% of its life at sea. It doesn't use its wings to fly, it uses them to swim.

4. Fish Fish are animals that live in water and have gills, scales and fins on their body. There are a lot of different fish and many of them look very odd indeed. There are blind fish, fish with noses like elephants, fish that shoot down passing bugs with a stream of water and even fish that crawl onto land and hop about!

5. Arthropods/Insects Arthropods - a huge class of animals. Any animals that have more than four, jointed legs are arthropods. Insects, spiders and crustaceans all belong to this class of animals. In order to be called an insect it must have all four of the following characteristics: six legs, three body part, antenna, and an exoskeleton.

6. Mammals Mammals are one of the 6 main classes of animals. Animal classes are groups of animals that scientists consider to be alike in some important ways. Mammals are the animal class that people belong to. There are only about 4,000 kinds of mammals. This sounds like a lot, but when you consider there are 21,000 kinds of fish and a 800,000 kinds of insects you’ll realize mammals are a pretty small class! Mammals are warm blooded. Mammal babies all drink milk! Mammals aren't spineless All mammals have fur or hair.

7. Reptiles Reptiles are a class of animal with scaly skin. They are cold blooded and are born on land. Snakes, lizards, crocodiles, alligators and turtles all belong to the reptile class.