Question

Birds and mammals share one of the following characteristics as a common feature:

• A. Pigmented skin
• B. Pneumatic bones
• C. Viviparity
• D. Homeothermy

Answer 1

The correct option is D Homeothermy

(a) Pigmented skin is the adaptive feature in mammals. It is not present in birds.
(b) Pneumatic bones are found only in birds as their flight adaptation. These reduce body weight for flight as these bones are filled with air.
(c) Viviparity means giving birth to young ones and is shown by mammals and not by birds as they are oviparous, i.e., lay eggs.
(d) Homeothermy (warm blooded) is a common feature shared both by birds and mammals. Warm blooded animals can maintain constant body temperature, irrespective of the surrounding environment, i.e., their body temperature is fixed.