A silkworm wraps itself in a fluid substance from its silk glands that hardens to become a cocoon — this cocoon can be unravelled to a single strand reaching lengths of 1.5 km (1 mile). Inside, it "digests" its own larval body (called histolysis) before building up the body of a silkworm moth.

The common cockchafer spends its first 3 to 5 years below ground, growing as a larva. Then, all at once, these beetles emerge as adults in great numbers during spring. They clumsily buzz about, using their frilly antennae to find mates and reproduce — they live for only 6 weeks in this form.