Why is it necessary to separate oxygenated and deoxygenated blood in mammals and birds?
It is necessary to separate oxygenated and deoxygenated blood to maintain efficient supply of oxygen into the body. This system is essential in animals that have high energy need. For example, animals like mammals and birds which constantly use this energy to maintain their body temperature.
Mammals and birds are warm blooded animals. Their energy requirement is high since they constantly require energy to maintain their body temperature. Hence, it is necessary to separate the oxygenated and the deoxygenated blood in mammals and birds as this separation allows a highly efficient supply of oxygen to the blood cells. This is important for producing a lot of energy and for maintaining the body temperature.