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.
Other Characteristics Not Unique to Mammals. Other characteristics not unique to mammals include live birth, determinate growth and a four-chambered heart. Some sharks give live birth to their young; whereas, two mammals, platypus and the echidna, lay eggs. Mammals are known to have determinate growth, but so do birds, and at least the American alligator.