Question

Why is it necessary to separate oxygenated and deoxygenated blood in mammals and birds ?​

Answer 1

Separation of oxygenated and deoxygenated blood allows good supply of oxygen to the body. This system is useful in animals that have high energy requirement. Mammals and birds constantly need oxygen to get energy to maintain their body temperature constant

Answer 2

Answer:

In birds and mammals have a double circulation system where both the oxygenated and deoxygenated blood maintains separate. ... They must separate oxygenated and de-oxygenated blood so that their circulatory system is more efficient and can maintain their constant body temperature.