When an Anthropod changes dramatically, it is called Complete Metamorphosis. Complete metamorphosis involves four stages: 1) egg, 2) larva, 3) pupa, and 4) adult. After a fertilized egg is laid, a larva is hatched. After a period of time, the larva builds itself a cocoon. The insect within the shell, now known as a pupa, is in a resting stage. It slowly undergoes a fairly dramatic change in its body structure and appearance. When the process of body reorganization has been completed, the pupa breaks out of its shell and emerges in its mature adult form, also called the imago.