In Unit II you learned that insects develop from egg to adult in stages. They grow and change from stage to stage by molting until the adult stage is reached. The development of an insect from egg to adult is called its life cycle. The way it changes form as it goes through its life cycle is called its metamorphosis. Different insects have different types of metamorphosis. You learned that there are four types:
Observing insects as they change from one stage to another is a very interesting project. Some insects can be easily observed through their entire life cycle in their natural habitat (living place). Others may be harder to observe for various reasons. Their life cycles may be long (several years sometimes), or they may live in special habitats where they are hard to observe, or they may jump or crawl from place to place so you cannot keep track of them. Some of these problems can be overcome by rearing the insects in cages.
When rearing insects in cages, it is important to know what food each kind will eat. You will also need to know what other habitat conditions they need such as moist, dry, shady, sunny, places to hide, soil to burrow in, etc. Try to duplicate the insect's natural living conditions as much as possible. These considerations will determine the kind of cages that will be suitable for rearing the insect. Sometimes you can use one kind of cage to rear the insect through part of its life cycle and then transfer the insect to another type of cage to complete its life cycle. Click here for examples of different types of cages and how they may be used.