How many chambers do the bird heart and the mammalian heart have? Concerning temperature maintenance what is the advantage of the double and complete circulation of these animals?
The bird and the mammalian hearts are divided into four chambers: right atrium, right ventricle, left atrium and left ventricle. Birds and mammals are homeothermic, i.e., they control their body temperature. The four-chambered heart and the double circulation provide the supply of more oxygenated blood to the tissues making possible a higher metabolic rate (mainly cellular respiration rate). Part of the energy produced by the cellular respiration is used to maintain the body temperature.