In spring, butterflies are busy again in Australian gardens, laying eggs on fresh new growth, and children start finding caterpillars on the veggies. It’s the perfect time to talk about one of nature’s most surprising changes. Here’s the life cycle of a butterfly for kids in plain words, the difference between a butterfly and a moth, two Australian butterflies to look for, how to watch caterpillars safely, and what children learn about life cycles at school.
The four stages of a butterfly’s life cycle
A butterfly doesn’t grow like a puppy or a joey, which look like small versions of their parents. It changes completely, more than once. The Australian Museum explains that butterflies and moths “look different at different stages of their life cycle”. This big change has a name: metamorphosis.
- Egg. A female butterfly lays tiny eggs on a plant her caterpillars will be able to eat. Each kind of butterfly has its own food plants. The Wanderer, for example, chooses milkweeds.
- Caterpillar (larva). A tiny caterpillar hatches and starts eating. The Australian Museum notes that caterpillars “have chewing mouthparts and mostly feed on plants”. As it grows, its skin gets too tight, so it sheds it, a few times over.
- Pupa (chrysalis). When it’s fully grown, the caterpillar fixes itself in place and sheds its skin one last time to become a pupa. A butterfly’s pupa is called a chrysalis. Outside it looks still, but inside, the body is being rebuilt.
- Butterfly (adult). A butterfly climbs out, waits until its wings are ready, then flies off to drink nectar, find a mate and lay eggs. Then the cycle starts again.
| Stage | What it looks like | Its main job |
|---|---|---|
| Egg | A tiny dot on a leaf, often smaller than a pinhead | Wait to hatch |
| Caterpillar | A soft, long body with many legs | Eat and grow |
| Chrysalis | A hard case hanging from a stem or leaf | Change into a butterfly |
| Butterfly | Two pairs of scaly wings and a long, tube-like tongue | Find a mate and lay eggs |
How long does it all take? It depends on the butterfly and the weather. The Australian Museum says the Wanderer can go from egg to adult “in as little as 25 days” in warm summer weather, and that it can take several weeks longer in a cool spring.
Butterfly or moth?
Butterflies and moths are close relatives. Both belong to a group of insects called Lepidoptera, which means “scaly wings”: the colours on their wings come from tiny overlapping scales. Moths are by far the bigger group. The Australian Museum says moths make up over 95% of the species in this group in Australia.
The museum gives some rules of thumb for telling them apart, with a warning that every rule has exceptions:
- Time of day. Butterflies are usually out during the day. Most moths fly at night.
- Antennae. Butterflies have a little knob at the end of each antenna. Many moths have thin or feathery antennae.
- Colour. Butterflies are often bright. Many moths are brown or grey.
- Resting. Butterflies usually rest with their wings held up together. Moths usually rest with their wings flat.
The pupa is different too. Many moth caterpillars spin a silk cocoon, while many butterfly pupae aren’t wrapped in anything at all and rely on camouflage or on tasting bad.
Two Australian butterflies to look for
The Wanderer (Monarch). A big orange-brown butterfly with black veins on its wings, and black and white spots around the edges. Its caterpillars have black, white and yellow stripes. They feed on milkweeds, and the Australian Museum explains that toxins from the plant’s milky sap make them taste bad, so their bright stripes are a warning to birds. Wanderers are common in Sydney in summer, and the museum lists them as uncommon in Victoria.
The Cabbage White. A white butterfly that is easy to spot over vegetable gardens. It isn’t native: the Australian Museum says it was first recorded in Melbourne in 1929, and had reached Sydney by 1941. Its caterpillars are velvety and green, and gardeners know them well because they eat cabbages, broccoli and cauliflower.
Spotting a butterfly is a lovely excuse to look closer at the plants around it. Who eats what in the garden is a great way into our post on food chains for kids.
Watching the life cycle at home
- Go on a leaf hunt. Check the undersides of leaves on veggies and garden plants for eggs, chewed holes and tiny caterpillars.
- Keep a photo diary. If you find a caterpillar, take a photo every day or two in the same spot. Children love seeing how fast it grows, and you can look for a chrysalis nearby later.
- Draw the cycle as a circle. Four boxes in a ring, joined by arrows: egg, caterpillar, chrysalis, butterfly, then back to egg. The Victorian Curriculum suggests showing life cycle stages with drawings, photos or models.
- Sort the babies. Make two groups: animals whose young change completely (butterflies, frogs, beetles) and animals whose young look like their parents (koalas, kangaroos, dogs, people).
- Plant for butterflies. A pot of flowers gives adult butterflies nectar. Ask your local nursery which plants suit butterflies in your area.
What children learn about life cycles at school
In Victoria, children from Prep (Foundation) to Year 2 learn that plants and animals “have external features that perform different functions to enable their survival”, including features that help animals “move, breathe, eat and respond to their environment” (VC2S2U03). Life cycles come up properly in Years 3 and 4: “plants and animals have different life cycles; offspring are similar, but not identical, to their parents” (VC2S4U02). The curriculum’s own example is comparing the metamorphic life cycles “of butterflies, beetles and frogs” with life cycles like our own.
KidStudy introduces the butterfly life cycle a little earlier, in a Year 2 lesson, because young children are fascinated by it and it builds on what they already notice in the garden. If your child loves living things, our sink or float experiment and kitchen science experiments are good next steps.
Questions parents ask
What are the four stages of a butterfly’s life cycle?
Egg, caterpillar (also called a larva), pupa (also called a chrysalis) and adult butterfly. The adult lays eggs, and the cycle starts again.
What is the difference between a chrysalis and a cocoon?
A chrysalis is the pupa of a butterfly, and many butterfly pupae are not wrapped in anything. A cocoon is a silk covering that many moth caterpillars spin around themselves before they become a pupa.
How long does it take a caterpillar to turn into a butterfly?
It depends on the kind of butterfly and the weather. The Australian Museum says the Wanderer can go from egg to adult in as little as 25 days in warm summer weather, and it takes longer in a cool spring.
Is it safe for kids to touch caterpillars?
It’s best to look without touching. Some Australian caterpillars, such as cup moth caterpillars, have stinging spines. Watch them where they are, and wash hands after time in the garden.
What do butterflies eat?
Caterpillars chew the leaves of their own particular food plants. Adult butterflies have no jaws. They drink nectar from flowers through a long, tube-like tongue called a proboscis.
Sources
- Moths, butterflies and skippers: Order Lepidoptera, Australian Museum
- What are the differences between butterflies and moths?, Australian Museum
- Wanderer Butterfly, Australian Museum
- Cabbage White Butterfly, Australian Museum
- Cup moths, Australian Museum
- Victorian Curriculum F–10 Version 2.0: Science, VCAA (VC2S2U03 and VC2S4U02)
