Kinda-sorta.
Puffing up feathers or hair allows it to hold more air, and more air means it becomes a better insulator. With a better insulator around you, less heat is lost to the surroundings. And with more heat staying inside, the inside gets warmer.
By puffing out their feathers in the cold birds create a larger insulating layer of air and feathers, which helps them retain body heat. Many mammals do the same with their fur.
water proof feathers
Birds are endothermic and maintain a constant body temperature through many of the same mechanisms that mammals use - restricting blood flow to extremities, rapidly twitching or contracting large muscle groups (shivering), puffing up their feathers and getting out of the wind/rain/snow.
They are essential for flight and to maintain body temperature
No, milk consumption does not lead to an increase in body temperature.
Down feathers are located underneath contour feathers. They are fluffy and provide insulation to help birds regulate their body temperature.
Increase
Increase the body temperature.
Do birds die? Well the answer is no, they don't. Birds have feathers, that's how they keep warm.
increase as kinetic energy is directly related to temperature. The molecules would move faster, increasing collisions and thermal energy, causing an increase in body temperature.
Down feathers are feathers that lie under a birds body and primary feathers. These feathers are small and puffy, and trap warm air under a bird's feathers.
To increase your body temperature.