Classification
What is Classification
• The process of putting things into
groups based on their similarities.
Why Classify?
•
•
•
•
To organize
To identify
To study
To observe patterns in nature.
Classification Systems
1. The first system was developed by
Aristotle.
a. 2 groups: animals & plants.
b. Animals divided into 3 groups:
i. Flying
ii. Walking
iii. Swimming
Classification Systems
c. List 2 animals that would fit in the groups
listed above.
d. What are some possible problems with this
classification system?
Classification Systems
2. The second system
was developed by
Carl Linne (aka
Carolus Linnaeus)
a. Developed the system
called binomial
nomenclature (twoname naming system).
Classification Systems
b. It uses Latin because it will never change.
c. The first name is the Genus and it is
ALWAYS CAPITALIZED.
i.
The genus is a group of closely related
organisms.
ii. Example: all bears are in the genus Ursus.
Classification Systems
d. The second name is the species and it is
never capitalized.
i.
The species name is specific to one type of
organism.
ii. Example: a polar bear is Ursus maritimus, a
grizzly bear is Ursus arctos, and a black bear is
Ursus americanus.
Classification Systems
3. Today’s Classification System
a. There are 8 levels, each level gets more
specific:
1.
2.
3.
4.
5.
6.
7.
8.
Domain – Example: Eurkaryota (has nucleus)
Kingdom – Example: Animalia (animals)
Phylum – Example: Chordata (has a backbone)
Class – Example: Mammalia (nurses young & has hair)
Order – Example: Rodentia (has long sharp front teeth)
Family – Example: Scuridae (has a busy tail)
Genus – Example: Tamiasciurus (climbs trees)
Species – Example: hudsonicus (has reddish fur on back
and white fur on underside)
Common Name: Red Squirrel
Classification Systems
4. The 6 Kingdoms
a. Animalia: insects, fish, worms,
mammals, birds
b. Plantae: trees, flowers, moss, grass
c. Fungi: mold, mushrooms, yeast,
penicillin
d. Protista: algae, amoebas, paramecium,
sea weed
e. Monera (aka Bacteria): salmonella,
streptococcus, E. coli
f. Archaea –single-celled prokaryotes
Classification Systems
5. Classification keys (aka dichotomous
keys & taxonomic keys)
a. A series of paired statements that
describe the characteristics of different
organisms.
b. Used to identify the name of species.
c. Example: office supplies
Dichotomous Key Rules
1. Read both choices.
2. Keep track of your choices – write the
sequence down.
3. If you aren’t sure which choice is
correct, try both and see which one
works best.
4. If you don’t understand a word, look it
up.