Taxonomic Levels“King Philip”

Carolus Linnaeus invented the Latin

binomial system for naming organisms (which we still use today) but he

also understood that organisms could be grouped and sub-

grouped into categories such as orders, families,

or kingdoms.

Traditionally, there are seven levels (called “taxa”)

in modern Linnaean taxonomy.

From largest to smallest, they are:

Kingdom

Phylum

Class

Order

Family

Genus

Species(Can you think of any clever ways to remember them in order?)

Hint: King Philip

The highest level is the Kingdom. Currently, we recognize six kingdoms, although it used to be just five.

(During the time of Linnaeus they only recognized three!)

1 Animals

2 Plants

3 Fungi

4 Protists

5 Eubacteria

6 Archaebacteria

Most people are familiar with plants, animals, and even fungi.

Protists are less familiar to us,

because most of them are

microscopic.

The two bacteria kingdoms are perhaps the most interesting of all!

(Did you know that there used to be only one bacteria kingdom, but it was divided

into two kingdoms when newly discovered primitive

bacteria, called archaebacteria (or “old

bacteria”) were found to be so different that they belonged in their own

kingdom!)?

Domains.In recent years, taxonomists have added an eighth

taxon (level) at the very top, above Kingdom.

It is called the “Domain”.

There are only three domains.

Archaebacteria and Eubacteria each have their own domains, and the other four kingdoms fit into the third domain (Eukarya).

They are categorized by the structure of their cells and by their DNA!

Even though he never new about archaebacteria, or even eubacteria, Linnaeus’ taxonomy system is how we

still classify organisms to this day!