How does a caterpillar become a butterfly?
Quick answer from Eartha
A caterpillar becomes a butterfly through an amazing change called metamorphosis. First it eats lots of leaves and grows big. Then it wraps itself in a hard case called a chrysalis. Inside, its body changes completely, and after about two weeks, a butterfly flies out. Wow, what a transformation!
The longer story
A butterfly's life starts as a tiny egg on a leaf. When it hatches, a caterpillar comes out and spends most of its time eating leaves to grow bigger and bigger.
Once it is big enough, the caterpillar finds a safe spot and forms a hard case around itself called a chrysalis, or pupa. This might look still and quiet on the outside, but huge changes are happening inside.
Inside the chrysalis, the caterpillar's body breaks down and rebuilds itself into a completely new shape, with wings, new legs and antennae. This whole process is called metamorphosis and can take around one to two weeks.
When it is ready, the butterfly pushes out of the chrysalis. Its wings are crumpled at first, so it waits and pumps fluid into them until they are strong enough to fly.
Try this at home: Draw the life cycle
- Draw four circles in a loop: egg, caterpillar, chrysalis and butterfly.
- Draw a simple picture in each circle showing that stage.
- Explain the story out loud, following your circles from egg back to egg.
Words to know
- metamorphosis
- A big change in shape that some animals go through as they grow up.
- chrysalis
- The hard case a caterpillar makes around itself before becoming a butterfly.
- life cycle
- The stages a living thing goes through from birth to adult.
For grown-ups: what is my child learning here?
Age band: 5-8
Curriculum link: Australian Curriculum v9 Science, AC9S2U01
The concept: Living things have a life cycle, and some insects change shape dramatically as part of growing up.
More classroom ideas are on our teachers page, and safety notes for families are on for parents.
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