regarding the previous example on polymorphism in many object-oriented languagesa method such as calculateiq(would need to be declared for the root class animal for the control loop shown on the previous slide to work properly all of the public methods and attributes defined for the root class would constitute the public interface of the class hierarchy and each class in the hierarchy would be free to provide its own implementation for the methods declared in the root class polymorphism in nutshell allows us to manipulate instances belonging to the different classes of hierarchy through common interface defined for the root class purdue university