In the vertebrate group there are 5 major classes.

Bony Fish

They live in water and have scales and fins.

The eggs are laid in water. The eggs have no shell.

They use gills to breathe under water.


They live both on land and in water. Hence, the name amphibian.

They have a smooth skin which they use for breathing under water and lay their eggs under water. The eggs have no shell.

They neither have teeth, nor a beak. They swallow their food whole.


These animals have scales on their body and lay their eggs on land. The eggs have a soft shell.

Some of them have legs. E.g. Crocodiles.

Some of them are limbless. E.g. Snakes.

Reptiles are cold blooded.


They have feathers instead of scales on their body.

They lay hard shelled eggs on land.

Birds have a beak for eating food.

Birds are warm blooded.


Mammals have hair on their body and give birth to young ones.

There are in total 19 orders of mammals.

Mammals are warm blooded.


These are mammals which feed on insects only.

Their body is specially made small, having a long snout.

There is very less space between the teeth.


They are the only mammals with wings.


These mammals have chisel like teeth for gnawing.


These are mammals living in the water.

They have a tail, fins and flippers for moving around in the water.

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