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Classification is the way in which all living things are placed into larger and larger groups or catetories that share similarities and a common ancestry.
The sequence of classification categories can be remembered by memorizing:
King Phillip, Come Out For Goodness Sake!
Kingdom: Most textbooks now list 6 kingdoms -- animal, plant, protists (amoebas and such), fungi, bacteria, and archaebacteria (also called extremophiles). Thanks for updating us Deb!!
Phylum: There are more than 30 phyla in the Animal Kingdom and 9 or 10 in the Plant Kingdom. Phylum Chordata is the one we're most familiar with -- it includes humans, birds, fish, and all other vertebrates (animals with a backbone). Phylum Arthropoda includes insects, spiders, lobsters, etc. Arthropods have segmented bodies with the segments grouped into two or three distinct sections. They have hard external skeletons, or exoskeletons, that are shed and regenerated as the animals grow.
Class: The various phyla are divided into classes -- Phylum Chordata is divided into the classes: amphibians, birds, mammals, reptiles and fish.
Order: Scientific groupings don't follow hard and fast rules. Once we get to the "order" of a living thing, there sometimes begins to be some disagreement about where it belongs. You may find that different sources group creatures in different orders or families. And you may find that a creature has its order or family changed as more information is learned.
Family: The family is a relatively new scientific concept. It is a way scientists group similar genuses together. This is not the "mom, dad, brother and sister" type of family!
Genus: Two or more species that share unique body structures or other characteristics are considered to be closely related and are placed together in a genus. Sometimes a genus might include only a single species if there is nothing else in the world that has similarities with it. The genus is the first part of the scientific name of a species. The genus is always spelled with a capital letter and in italics.
Species: A species can be defined as a group of individuals that breed together to produce fertile offspring. Individuals of a species cannot breed with other such groups. It is sometimes possible for different species to breed, but the offspring will be sterile. A mule is the sterile offspring of a donkey and a horse, and the mule can never mate and reproduce itself. The species is the second part of the scientific name of a species. The species is always spelled with a lower case letter and in italics.