Life cycles of insects
All insects start as eggs.
There are 2 different types of life cycle:
- young stages (nymphs) look similar to adults. In a cicada, for example:
- a nymph hatches out of the egg;
- the nymph then feeds on the roots of plants underground, often for several years;
- the nymph looks a bit like the adult cicada, but it is white and has no wings;
- during this time as a nymph it sheds its skin several times and grows bigger and bigger;
- eventually it crawls out of the ground and climbs up a tree where it sheds its skin for the last time;
- it emerges from its nymphal skin as the adult cicada with its wings;
- young stages (larvae) look different from the adults. In insects like butterflies, beetles, and flies:
- the egg hatches into a caterpillar or larva;
- the larva feeds for anything from days to several years (different insects have larvae feeding on many different types of food);
- the larva looks very different from the adult insect;
- when the larva sheds its skin for the last time it becomes a pupa;
- the pupa is a resting stage; it is usually fixed in one place, often inside a cocoon made by the larva, and it can't move much;
- inside the pupa the body of the larva breaks down into a kind of living soup, and reorganises itself into the adult insect;
- these big changes in the life cycle of insects are called metamorphosis, which is a Greek word meaning "change of shape" or "transformation".
