1. Biologists use seven levels of classification.
Notes for 2.2 B
Biologists use seven levels of classification.

2. Linnaeus named about 4000 species.
All 4,000 organisms Linnaeus named were plants or animals.
Today, scientists have named over a million species.
Linnaeus used appearance to classify organisms.

3. Naming Species
genus—a group of species that have similar characteristics
binomial nomenclature—a two-word naming system developed by Linnaeus (genus, species)
Chameleo graciis

4. Naming Species (cont’d.)
binomial--two names
nomenclature—list of names
Ursus arctos

5. Using Scientific Names
The scientific name must include both the genus and species names in order to be clear.
Rules to follow:
Genus names comes first; the first letter is capitalized, and the entire name is in italics or underlined.
Species name is also italicized but not capitalized.
Rhodedendron maximum

6. Organisms can be classified into seven levels.
Major Taxonomic Levels
Kingdom
Phylum
Class
Order
Family
Genus
Species
Note: There are many subdivisions of the seven main taxonomic levels, such as Subphylum, Subclass, Infraclass, and so on. You may see many of these other sublevel taxa listed in the taxonomic tree of an organism. See pages for examples.

7. Cont’d.
In order to remember the levels of classification, create a memory aid such as:
King
Phillip
Called for an
Order of
Fried
Great
Swordfish.

8. Dichotomous keys and field guides help people identify organisms.
dichotomous key—a series of paired statements, each with only 2 answers, that can be used to identify an organism’s genus and species
will give you the scientific name
See page 57B for an example.

9. Field Guides
Field guides include paintings or photographs, maps, and other information .
See page 58 B for an example.