Describe the class Mammalia.

(1) Found in variety of habitats – polarice caps, deserts, mountains, forests, grasslands, dark caves, some can fly or some can survive in water.

(2) They have milk producing mammary glands to feed youngones.

(3) They have two pairs of limbs for walking, running, climbing, burrowing, swimming or flying.

(4) They have hair or body.

(5) External types of teeth are present.

(6) Different type of teeth in their jaws.

(7) Heart is four chambered .

(8) Homoiothermous .

(9) Respiration by lungs.

(10) Sexes are separate & fertilization is internal.

(11) Mostly Viviparous and development is direct, with exceptions