Mammals are warm-blooded animals with four chambered hearts. Their skin is covered by hair, sweat glands and oil glands that regulate body temperature. Mammals give birth to young ones. They have mammary glands for the production of milk to nourish their young ones. Mammals like platypus lay eggs. Kangaroos give birth to under-developed young ones that are carried in their mother’s abdominal pouch.
Eg: Human, rat and cat etc.