The mother hen keeps the body temperature of the young chicks regulated by sitting on them and fluffing her feathers. This maintains the temperature at about 100 degrees Fahrenheit, which is the optimum temperature for the chicks to grow. The mother hen also won't leave the chicks until they are able to regulate their own body temperature, which takes about two weeks. Once they are able to regulate their own body temperature, the mother hen will start to spend less time with them. Although she will still check on them periodically, she will no longer need to sit on them all the time. The chicks will also start to explore more and will begin to eat solid food.