In short
The taxonomic hierarchy is the ranked list of groups used to classify living things, from the largest group down to a single species: kingdom, phylum, class, order, family, genus, species.
Each level contains the levels below it. Organisms in the same species are the most alike, and organisms in the same kingdom share only a few broad features. A common memory aid is King Philip Came Over For Good Soup. In plants the second rank is usually called a division. The rank above kingdom is the domain.
The lion: Kingdom Animalia, Phylum Chordata, Class Mammalia, Order Carnivora, Family Felidae, Genus Panthera, Species leo. This is why lions belong to the class Mammalia.
Also searched as: species genus order, species hierarchy, what does class mean in science, what are the classes of living things.
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