Figure 3.

The structure of feathers and thermoregulation in birds: The plumulaceous part and downy feathers are the main structures involved in thermobalance. When exposed to cold weather, birds adopt behaviors such as fluffing their feathers to trap air between them and their skin. This prevents heat dissipation and preserves warm air that raises their body temperature. However, during hot weather, the feathers’ insulating function leaves birds susceptible to heat stress by reducing their ability to thermoregulate efficiently.