​Classifying vertebrates

​Vertebrates are animals with backbones. They are classified into

five groups called classes.

​Fish

​Fish are vertebrates with fins. Their skin is covered with scales. They breathe using gills. They lay eggs in the water.

​Amphibians

​Amphibians include frogs, toads,

newts, and salamanders. The

adults live on land and breathe

using their lungs. They have four

limbs. They lay eggs in water.

The young are called tadpoles

and develop in water where they

breathe using gills. Amphibians

have smooth skin without scales.

​Reptiles

​Reptiles are vertebrates with

scaly skin. Most of them have

four legs, although snakes have

no legs. Some reptiles

live on land, but some-such

as crocodiles - live in water.

Reptiles reproduce by laying

eggs on land.

​Birds

​Birds are vertebrates with wings,

feathers and a beak. They lay

eggs on land.

​Mammals

​This is the group that humans

belong to. Mammals are

vertebrates with hair. Mammals

give birth to live young, which

are fed on milk from the mother.

​Summary

• ​Vertebrates are animals with backbones.

• Vertebrates are classified into five classes - fish, amphibians,

reptiles, birds, and mammals.