When I was talking with my Dad about the problem of frozen combs/wattles, he asked about whether chickens tuck their heads under their wings at night. I guess they don't because otherwise there wouldn't be an issue about frostbite. Why don't they? (Can we please reintroduce a few brain cells back into chicken genetics, and develop a breed that will do this?) I suppose it is not possible to train a chicken to put its head under its wing...? That would be just too useful.