Show animals and mammals all mammals are animals comparatively ively few animals possess the characteristics necessary for classification fi as mammals mammals comp comprise r ise the highest class of an animals their outstanding characteristic is that they nourish their young with milk mammals are covered more or less with hair possess main mammary mary glands a muscular diaphragm which separates separate s the heart and lungs from the abdominal ca cavity V and red blood corpuscles corpus cles without nuclei |