1.1. Mammals

Characteristics of Mammals

Mammals are vertebrates with the following characteristics:

- They are viviparous. This means that the young develop inside the female’s body. The female mammal then gives birth to the live young.

- They look after their young. After they are born, young mammals feed on their mother’s milk.

- They are the only animals to have a body covered in hair or fur.

- The majority of mammals are terrestrial and have four legs, which they use to walk with.

 Some mammals, like dolphins and whales, live in the sea and have fins to swim with instead of legs. Bats are the only mammals that can fly. They can fly because they have wings.

- Mammals are warm-blooded animals. This means that they keep their body temperature at a constant level.

When it is cold, their fur and the layer of insulating fat beneath their skin helps to retain body heat and keep them warm. When they are too hot, they lose heat through their skin by sweating