Erythropoiesis (from Greek 'erythro' meaning red and 'poiesis' meaning to make) is the process which produces red blood cells (erythrocytes).
Birds and mammals have the following characteristics in common: they are vertebrates, meaning they have an internal skeletonthey are warm-bloodedthey breathe using lungs, so â¦ have full respiratory systems they have circulatory systems. Most mammals give live birth, but there is a sub-group known as monotremes, which are the egg-laying mammals. 2  This group includes just the platypus and the echidna. 3  They are still mammals because, like all mammals, they feed their young on mothers' milk.
In some areas, birds are similar to other animals, and in others, they are absolutely unique. For example, the bird has several unique adaptations that enables it to fly, including feathers, air spaces in bones, a beak in place of teeth and lips and the bones of the hand fused to support flight.ird lungs are located more against the bones of the back, and are relatively non-expansible. They are smaller by about 25% than those found in mammals. Birds do not have a diaphragm, as mammals do. Birds breathe by expanding the ribcage outward, which draws air in like a bellows.