Taxonomy – the science of classifying organisms
Why do we need a system to classify and name organisms?
Here are some common names:
spider monkey | sea monkey | sea horse |
gray wolf | firefly | crayfish |
mud puppy | horned toad | ringworm |
black bear | jellyfish | spiny anteater |
These names can vary by region and can also be misleading. Is a sea horse really a horse?
Naming Organisms:
Organisms have common & scientific name -all organisms have only 1 scientific name
-usually Latin or Greek
-developed by Carolus Linnaeus
This two-word naming system is called…..
Binomial Nomenclature
-written in italics (or underlined)
-1st word is Capitalized –Genus
-2nd word is lowercase —species
Examples: Felis concolor, Ursus arctos, Homo sapiens, Panthera leo , Panthera tigris. These can also be abbreviated as (P. tigris or P. leo)
Linneaus also devised the system we use to organize animals. This system uses large groups divided into subgroups (like the way you organize folders on your computer)
Kingdom — Phylum — Class — Order — Family — Genus — Species
Human | Lion | Tiger | Pintail Duck | |
Kingdom | Animalia | Animalia | Animalia | Animalia |
Phylum/Division | Chordata | Chordata | Chordata | Chordata |
Class | Mammalia | Mammalia | Mammalia | Aves |
Order | Primate | Carnivora | Carnivora | Anseriformes |
Family | Homindae | Felidae | Felidae | Anatidae |
Genus | Homo | Panthera | Panthera | Anas |
Species | sapiens | leo | tigris | acuta |
Each organism has a group and subgroups. The organisms with the most similar groups will be most closely related. Note that both the lion and the tiger are in the same genus, but are considered to be separate species.
There are currently 6 kingdoms – organisms are placed into the kingdoms based on the number and type of cells they have, and their nutritional needs.
number of Cells |
energy | cell type |
examples | |
archaebacteria | unicellular | some autotrophic, most chemotrophic |
prokaryote | “extremophiles” |
eubacteria | unicellular | autotrophic and heterotrophic |
prokaryote | bacteria, E. coli |
fungae | most multicellular |
heterotrophic | eukaryote | mushrooms, yeast |
plantae | multicellular | autotrophic | eukaryote | trees, grass |
animalia | multicellular | heterotrophic | eukaryote | humans, insects, worms |
protista | most unicellular |
heterotrophic or autotrophic |
eukaryote | ameba, paramecium, algae |
Additional Links on Taxonomy
Build a Cladogram | Tree of Life Web Project