Insect Lifecycles

Life Cycles

Everything has a lifecycle: plants, animals, insects and spiders. There are two common kinds: complete and incomplete and a third less common one called hypermetamorphosis.

A complete metamorphosis involves a pupation stage and an adult that looks nothing like its young.

An incomplete metamorphosis does not include a pupation stage and the young look like smaller versions of the adult, until at last they become adult themselves as they grow.

Hypermetamorphosis is where the first instar larva is completely different to the rest of the larva instars. For example, oil beetle larvae have developed legs and are called triungulins, they look for a way to get to their host (solitary bees) and begin feeding (watch out for the forthcoming oil beetle blog), but when it moults for the first time it changes into a the usual beetle grub shape, then pupates as per normal and emerges as an adult beetle.

Some butterfly larvae look like bird droppings in their first, sometimes second and third instar – this is not hypermetamorphosis.

Many insects undergo both a complete and incomplete metamorphosis.

Butterflies have a complete metamorphosis.

It includes, egg, larva, pupa and adult (imago if you want to be really sciency).

The butterfly chooses the right plant for her caterpillar to eat and lays her eggs on it.

The eggs hatch into the baby caterpillar.

The caterpillars eat the leaves and grow, shedding their skins five times before becoming a pupa. Inside their skins they grow until the skin cannot stretch any more, they then form a new skin under the old one. When that is ready they moult to be able to grow into the new skin. After the forth moult, the pupa begins to form under the last of the caterpillar’s skins, and the fifth moult is from caterpillar to pupa.

Inside the pupa, or chrysalis as it is also known, the tissues of the caterpillar’s insides break down and rebuild into the new body of the adult butterfly, or moth, as moths share the same process too. Depending on species, pupation can take as little as two weeks, or eight months in the case of the orange tip butterfly as this is their overwintering stage, even up to two years in the case of small eggar moths.