In this cold weather large combs can attract frostbite so you may like to rub Vaseline into the comb to help prevent this. Combs and wattles are actually used to cool a chicken down in hot weather. The comb sticks up and stays cooler than the rest of the body. When the blood goes into the comb it cools down, before circulating back into the body.
I was watching one of my cockerels recently who had found some food and was performing to attract his favourite hens. He repeatedly picked up the food and dropped it but also bobbed his head up and down and swung it from side to side. The wattles were swinging about and even smacking him on the head. Apparently there has been some research carried out on this phenomenon and it is thought that cockerels have wattles to make the food display more conspicuous. The cockerel’s red wattles are also a general feature to help attract females.
Long red wattles are ideal for courting