This page provides some background information about the classification of living things. This is an important part of the Web of Life unit and is part of the year 4 science curriculum (ACSSU044).

The system we use was original invented by Carl Linnaeus, although many parts of it have been changed since he published it in the 1700s. This system is known as Linnaean taxonomy.

The classification system is a hierarchy, with the main levels being Kingdom, Phylum, Class, order, family, genus, species. You can see a picture of it on the Wikipedia Biological classification page. In this unit we primarily concern ourselves with distinctions at the Class level, students are not required to know about the full classification system at this stage.

The main classes considered in this unit are:
Mammals, fish, reptiles, birds, insects, arachnids, amphibians.
Note that above the class level, this list is divided into two phyla: Mammals, fish, reptiles, birds and amphibians are all Chordata (vertebrates) and insects and arachnids are both Arthropods (exoskeletons).

Arthropods make up 85% of the known animals in the world, and arthropods are/have:
  • A segmented body
  • Many jointed legs or limbs
  • An exoskeleton
  • Are cold blooded


Some pages with information on the main classes include: