Which of the following behaviors allows a bird to maintain a constant body temperature in extremely hot weather?

a. Spreading wings

c. Flattening feathers

b. Panting

d. All of the above

d. All of the above

These behaviors;

Spreading wings

Flattening feathers

panting

are all evolutionary process to maintain body temperature. Birds are warm-blooded animals. Also known as homeotherms, which is defined as having the constant body temperature. This is a vital function for the survival of the specie.