Glossary
Rank
A level in the classification hierarchy, such as genus, family or order.
The main ranks used on this site, from broadest to narrowest, are kingdom, phylum, class, order, family, genus and species. Each animal’s page shows its place at every rank.
Classifications also use in-between ranks such as subfamily or superorder; these are not shown here.
Related terms
- Kingdom
- The broadest rank used here. All animals belong to the kingdom Animalia.
- Phylum
- A major division of a kingdom, grouping animals that share a basic body plan.
- Class
- A rank below phylum. Mammals (Mammalia) and birds (Aves) are classes.
- Order
- A rank below class. Carnivora, the order of cats, dogs, bears and their relatives, is one.
- Family
- A rank below order, gathering related genera. Animal family names end in -idae.
- Genus
- A rank below family: a group of closely related species. It is the first word of a scientific name.
- Species
- The basic unit of classification: a group of organisms treated as one kind and given a two-part scientific name.