We believe that chickens are not blessed with great intelligence, but the 'chicken- language’ is more extensive than most people think. Chickens do produce 30 to 40 different sounds, all of which have a different meaning. They warn each other for instance with an air-raid alarm: when a bird of prey is flying over, they make a kind of squeaking, creaking sound, while in the case of danger on the ground, they will cluck in panic. This communication even takes place while the chickens are still in the egg. A mother hen passes her knowledge to her chickens and they answer with squeaks through the eggshell. Young chickens are nidifugous, which means that after hatching, they are immediately able to walk and search for food, although they will spend the first few days mostly in the soft, warm down of the mother hen. When the mother finds that they are too pig-headed or when they wander off, by the time they get more independent, she will recall them with her clucking. The crowing of a rooster has developed into a regular season-independent cry, which predominantly serves for demarcation of the territory.