ABSTRACT
There are, supposedly, more than two million different kinds of plants and animals on Earth. In order to study, or even to identify them, they have been classified into groups. The basis of classification is similarity and difference – how are the members of a group similar, and how do they differ from all other groups? These questions can be asked repeatedly until it is possible to identify individual types of plants or animals (these ideas are explored further in Concepts to Support Key Stage 2, below).
