There are billions of different kinds of living things (or organisms) on earth. To help study them, biologists have devised ways of naming and classifying them according to their similarities and differences.
The system most scientists use puts each living thing into seven groups (or taxons), organized from most general to most specific. Therefore, each species belongs to a genus, each genus belongs to a family, each family belongs to an order, etc.
From largest to smallest, these groups are:
Kingdoms are huge groups, encompassing millions of kinds of organisms each. All animals are in one kingdom (called Kingdom Animalia); all plants are in another (Kingdom Plantae). In the most widely-used system, there are five kingdoms, containing animals, plants, fungi, prokaryotes, and protoctists (the last two are different sorts of one-celled organisms). Other systems have six or more kingdoms.
Species are the smallest groups. A species consists of all the animals of the same type, who are able to breed and produce young of the same kind. For example, while any two great white sharks are in the same species, as are any two makos, great whites and makos are in different species (since they can't interbreed).
A Sample Classification
The lion belongs to the following groups:
For more, see Examples of Scientific Classification
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