A butterfly does not start life as a butterfly. It starts as a tiny egg on a leaf. Then it changes, and changes again, in one of the biggest makeovers in nature.
Key idea
Egg → caterpillar → chrysalis → butterfly. It is the same animal the whole time.
Why it works
A caterpillar is an eating machine. It eats leaf after leaf and grows much bigger, shedding its skin as it goes. Then it stops, forms a chrysalis, and its body is rebuilt inside. When the butterfly comes out, it is done growing.
Worked example: Let's think it through
You see a big butterfly and a small one. Is the small one a baby?
- A butterfly comes out of its chrysalis full size.
- It does not grow after that.
- All of its growing happened as a caterpillar.
Answer: No. The small one is a grown-up too, maybe of a smaller kind.
Common mistake
Children often think the caterpillar and the butterfly are two different animals, or that a butterfly keeps growing. It is one animal, and it does all its growing as a caterpillar.
For the grown-up. In late summer, look for striped monarch caterpillars on milkweed plants. The whole change from egg to butterfly takes about a month in warm weather.