Animals that live in cold places find it difficult to survive winters. So, they leave their homes and travel to warmer places in search of food and shelter. Such a mass movement of animals from one place to another is called migration.

Some animals cannot tolerate extreme cold. In order to survive, they eat a lot of food and then go to sleep in their caves, holes under the ground during winter. This is called hibernation. Some land animals like snakes, lizards, bears, rodents and frogs hibernate.

The animals that live in or on the body of other animals are called parasites. They obtain food from the animals, on which they live. They depend on its host for survival, and they might cause disease.

Camouflage is the ability of an animal to merge with its surrounding so that it cannot be seen by its enemy. A chameleon can change its colour of the skin in order to blend with its surroundings, whenever it feels unsafe.