It is the process by which insects undergo change from egg to adults. There are 2 type of metamorphosis; complete and incomplete metamorphosis

1. Complete metamorphosis;

Complete metamorphosis involves 4 stages which are: egg, larva, pupa and adult. The adult female lays eggs. These eggs later hatch into larva which do not resemble the parents. In complete metamorphosis, it is the larva who feeds. When it outgrows the skin, it undergoes moulting (removal or falling off of old skeleton). It is at the larva stage that insects do a lot of damage to man’s crops and gardens.

After several moultings, the larva stops feeding and becomes inactive. Depending on the species of the insect, it may produce silk cotton or form a hard covering before becoming dormant at this stage, it is called a pupa.

The pupa then undergoes many changes to become an adult.

Example of insects that undergo metamorphosis are flies, bees, mosquitoes and butterflies.

The diagram below illustrates complete metamorphosis

Egg

                              Adult                               Larva

Pupa

2. Incomplete metamorphosis;

In complete metamorphosis, the male and the female mate and the female later lays eggs which are eventually hatched into young ones called nymphs. The nymphs resemble the parents but they lack wings and reproductive organs and also smaller in size than the parents. The nymphs then grow and moult (shed their exoskeleton) about 5 to 7 times. The stages between the moults are called Instars. The wings and the reproductive organs are formed as the nymph grows and moult into adult.

Example of insects that undergo incomplete metamorphosis are grasshoppers, cockroaches. The diagram below illustrates incomplete metamorphosis

                                             Egg

                                           Adult                                Nymph

Differences between complete and incomplete metamorphosis