Insects

The largest class of animals, and how to recognise one.

Insects are arthropods with three body segments — head, thorax, abdomen — six legs, and usually one or two pairs of wings. The leg count is the quickest field check: spiders have eight and are not insects.

Metamorphosis

Complete metamorphosis runs egg, larva, pupa, adult, with larva and adult often unrecognisable as the same animal and eating different food. Incomplete metamorphosis runs egg, nymph, adult, the nymph resembling a small wingless adult.