Caste: in social insect colonies, a group of individuals that are structurally and/ or behaviourally distinct, performing certain tasks. Examples are the soldier caste of termites and ants, and the workers of bees.
Invertebrate: animals with no backbone.
Larvae (plural): stage in an animal’s lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.
Pupa; pl. pupae: stage in an insect’s development when huge changes occur, which reorganise the larval form into the adult form. In butterflies the pupa is also called a chrysalis.