The Life Cycle of a Butterfly

One animal, four shapes

A butterfly does not start life with wings. It changes its body shape completely as it grows. This amazing change is called metamorphosis. A butterfly's life has four stages: egg, caterpillar, chrysalis and butterfly. Let's follow the journey.

Stage 1: The egg 🥚

A mother butterfly lays tiny eggs, usually on the underside of a leaf. She chooses a plant that her babies will be able to eat. The eggs are very small — about the size of a pinhead. After a few days, something hatches out.

Stage 2: The caterpillar 🐛

Out of the egg crawls a hungry caterpillar. Scientists also call this stage the larva. The caterpillar has one main job: to eat! It munches leaves all day and grows very fast. It grows so quickly that its skin gets too tight, so it sheds its old skin several times. This is called moulting.

Stage 3: The chrysalis

When the caterpillar is big enough, it stops eating. It hangs from a twig or leaf and forms a hard case around its body called a chrysalis (also called a pupa). From the outside it looks still, but inside, something incredible is happening. The caterpillar's body is breaking down and rebuilding into a butterfly. This is the real magic of metamorphosis.

Stage 4: The butterfly 🦋

After one or two weeks, the chrysalis splits open. A butterfly climbs out! At first its wings are soft, wet and crumpled. The butterfly pumps fluid into its wings and rests while they dry and harden. Then it flaps its colourful wings and flies away.

The adult butterfly drinks sweet nectar from flowers using a long, curled tongue called a proboscis. Soon it will find a mate, lay eggs of its own, and the whole cycle starts all over again.

Why it matters

Butterflies are not just beautiful. As they move from flower to flower drinking nectar, they carry pollen. This helps plants make seeds and fruit, just like bees do.

Watch a life cycle

In late spring or summer, look on the leaves of plants like nettles or cabbages for caterpillars. With a grown-up's help, you can gently keep a caterpillar in a netted tub with fresh leaves and watch it grow, form a chrysalis and become a butterfly. When the butterfly hatches, set it free outside. Keep a diary and draw each stage you see.

To see how butterflies fit into nature, read Food Chains and Ecosystems. And to learn how the flowers they visit are built, read The Parts of a Plant.