They do not have an external ear, but rather a round opening that is surrounded by a disc and hidden by tiny feathers. Chickens communicate by voice and gestures. Crowing announces the morning just at the break of dawn. The hen's loud, excited cackle announces an egg just laid. Clucking sounds are the distinctive voice sounds of a broody hen and the contact assurance of a mother for her chicks.
Chickens require light, warmth, and shelter from wind and drafts.
Despite their love of warmth, chickens tolerate heat poorly, since they have no sweat glands to allow perspiration. Therefore adequate shade must be provided. They spend most of their time busily picking and scratching for food, and actively dusting and preening their plumage. They clean and preen their feathers in a leisurely fashion several times a day. With their beaks they put each and every feather in its right place, and then preen them by distributing oil over them.