male Wyverns collect shiny objects in their dens to attract mates it quite common for Wyverns to get into territorial fight. Now Wyverns are capable of breathing fire but they are also covered in feathers (which are quite flammable). In order to combat this Wyverns have developed flame retardant feathers. the question i want know is how might flame retardant feathers work?
NOTE: magic does not exist in my story