Classification of Living Things

Classification of living things is called "Taxonomy." This is when scientists put organisms into groups when they have things in common. The first groups they use are the Kingdoms. There are five kingdoms:

Animal Kingdom

Plant Kingdom

Fungi Kingdom

Protist Kingdom

Moneran Kingdom

Each Kingdom is then split into smaller groups, called Phyla. Each Phylum is split into smaller groups called Classes, each Class is split into Orders, each Order is split into Families, each Family is split into Genera, and each Genus is split into Species. A Species is a single organism, not a group. Some examples of species would be Southern Leopard Frog, Honey Mushroom, or White Oak. All seven types of groups go in order from largest to smallest, like this:

Kingdom

Phylum

Class

Order

Family

Genus

Species

As each group is split into smaller groups, the organisms are more and more alike. For instance, a White-tailed Deer, an Eastern Gray Squirrel, and an Eastern Chipmunk are all in the Mammal Class together. This is because they have more in common with each other than with other animals, such as turtles, birds, or insects. However, it is easy to notice that there are some big differences between a deer and squirrels and chipmunks. The White-tailed Deer is in the Aritiodactyla Order (Even-toed Hoofed Mammals), while squirrels and chipmunks are both in the Rodentia Order (Rodents).

In fact, squirrels and chipmunks have so much in common, they are also in the same Family, the Sciuridae Family. However, even though squirrels and chipmunks are very much alike, they still have differences. The Eastern Gray Squirrel is in the Sciurus Genus, while the Eastern Chipmunk is in the Tamias Genus.

Did you notice that these groups have funny names? Scientists from around the world agreed to use the ancient language of Latin to give organisms, and their groups, names. Sometimes a group will have a "Common Name" and a fancy, scientific Latin name. For example, there is a Family of frogs called "Ranidae" (Scientific Latin name). This Family's common English name is "True Frogs." Sometimes this gets confusing.

Every Species gets a fancy scientific Latin name. A Bullfrog is also known as "Rana catesbeiana." A White-tailed Deer is known as "Odocoileus virginianus." A Monarch butterfly is known as "Danaus plexipus."

One thing that makes it easier to understand all these names is to know that a Species always has a first and a last name; and that the first name is also the name of the Genus group that Species is in. So the Monarch butterfly is known as Danaus plexipus and it is in the Danaus genus. Notice that the first name of a Species is always capitalized, while the second name is not.

Here is the classification of a Bullfrog, so you can see all the groups it is in:

Bullfrog (Rana catesbeiana)

Kingdom: Animal

Phylum: Chordate

Class: Amphibians

Order: Salientia

Family: Ranidae

Genus: Rana

Species: Rana catesbeiana (Bullfrog)

As you explore the website, you can see an organism's classification at the bottom of each Species Page. This way you can compare organisms to see which ones are in the same groups, and you can try to figure out why scientists put them together. Below are two examples of classifications that are found at the bottom of the Eastern Gray Squirrel page and the White Oak Page. Notice that with plants, Phyla are called "Divisions."

Eastern Gray Squirrel:

SCIENTIFIC CLASSIFICATION

KINGDOM
Animal
PHYLUM
Chordate
CLASS
Mammal
ORDER
Rodentia
FAMILY
Sciuridae
GENUS
Sciurus
SPECIES
Sciurus carolinensis

White Oak:

SCIENTIFIC CLASSIFICATION

KINGDOM
Plant
DIVISION
Magnoliophyta
CLASS
Magnoliopsida
ORDER
Fagales
FAMILY
Fagaceae
GENUS
Quercus
SPECIES
Quercus alba

Once you learn how classification works, it is easy to study a group of organisms and it is fun to compare them.

To learn more about particular groups of organisms, click the link below:

Classification Group Explanations

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