Are caterpillars insects? And other caterpillar facts

Caterpillars are among our most unusual looking wildlife, well-known for their spectacular transformation into butterflies or moths. But how much do you know about these curious creatures? Discover more with these fascinating facts.

What is a caterpillar?

A caterpillar is the larva of a butterfly or moth. It’s the second stage in its four-stage life cycle of egg, larva, pupa and adult.

Are caterpillars insects?

Yes. Caterpillars are insects, just like their parent butterflies or moths. They have six proper legs, like all insects, but also up to five pairs of stumpy prolegs with little hooks that help them to hang onto things, and to move in a wave-like motion.

What do caterpillars eat?

Mostly plants. Many species have a favourite plant, such as a type of tree or grass, or even stinging nettles. These are known as host plants. The butterfly or moth will lay its eggs on a host plant, so the caterpillars have a ready source of food when they hatch.

What happens after the caterpillar stage?

Butterflies and moths go through a process called metamorphosis, which means ‘changing shape’, throughout their life cycle. After the egg and caterpillar stages, comes the pupa stage (also called the chrysalis). During this stage, the caterpillar develops a hard outer case, or sometimes a silk cocoon, to protect it while it turns into an adult butterfly or moth.

How do caterpillars make cocoons?

It’s usually moth caterpillars that make cocoons. They make liquid silk in their salivary (spit) glands and then drool it through an opening in their lip called a spinneret. It hardens into a thread when it comes into contact with the air and the caterpillar wraps it round itself to make the cocoon.

Do caterpillars have teeth?

Not exactly, but they do have two tooth-like mouth parts called mandibles that they use to bite and chew. They work from side-to-side, not up and down like our teeth.

Where do you find caterpillars?

Look on the undersides of leaves, in the grass, in hedges and among clumps of nettles. Plants with holes gnawed in the leaves are a sure sign of caterpillar presence.

Is it okay to touch a caterpillar?

Most caterpillars are harmless, but some hairy caterpillars can cause a skin rash if touched. For your own safety, and that of the caterpillar, it’s best to admire them from a distance.