Classification
Biology I
Aristotle
384-322 b.c.
• Classified things
based on if they are
plant or animal
• Classified animals
based on how they
look into land, water,
or air dwellers
• Grouped plants based
on stem structure
The Science of
classifying organisms
is called TAXONOMY
The father of modern
taxonomy is Carolus
Linnaeus (17071778)
Living organisms are
classified based on
how closely related
they are to one
another in a system of
taxa
1707-1778
The Old System
Grouped on cell type,
single or multi
cellular, moving or
stationary
6 Kingdom Proposal
Now, the Monerans are broken into two groups of bacteria
Archebacteria
EUbacteria
Kingdom Animalia
Phylum
Echinoderms
Phylum
Porifera
Phylum
Chordata
Class Reptiles
Class Aves
Class
Mammalia
Order Cetacea
Order Primates
Order Carnivora
Binomial nomenclature is a two-name
naming system
The first part of the name is the genus
of the organism and is always
capilalized,
The second part of the name is the
species and is always all lower case
The entire name is underlined and
italicized and are usually Latin based
Ursus americanus
American Black Bear
Often names contain clues about the type of organism being described
Canus domesticus
Canus lupus
Closely related organisms are often in the same genus
Domain Archaea
Formerly part of the kingdom monera
Microbiologists who study bacteria
determined that the DNA of these are
much different from other, true bacteria
Most Archaea live in extreme conditions
(very hot, acidic/basic, sulfurous, etc)
Domain Eubacteria
 Name means “true
bacteria”
 These are the kind of
bacteria likely to make
us sick, live in our gut to
help us digest food, or
be used in the making
of cheese
Domain Eukarya
Contains all of the eukaryotes (organisms with a nucleus in their cells)
Protista, Fungi, Plantae, Animalia
Kingdom Protista
unicellular, eukaryotic, heterotrophic
Amoeba
Paramecium
Water Mold
Euglena
Giardia
Slime Mold
Dinoflagellates Green Algae
Brown Algae
Diatom
Kingdom Fungi
All eukaryotic, multicellular,
heterotrophic, sessile organisms
Includes: molds, mushrooms,
rusts, lichens
Kingdom Plantae
eukaryotic, multicellular, autotrophic,
Bryophyte
(Moss)
Pteridophyte
(Fern)
Pteridophyte
(Fern)
Coniferophytes
(Pine Trees)
Angiosperm;
Dicot
Angiosperm;
Monocot
Kingdom Animalia
Human Classification
Dichotomous Keys
1a. Organism has 4 legs
Go to # 2
1b. Organism has more than 4 legs
Go to # 20
2a. Organism has a tail
Go to # 3
2b. Organism has no tail
Go to # 35
3a. Organism has stripes
Bengal Tiger
3b. Organism has no stripes
African Lion
Dichotomous Keys
• Tool Scientists use to identify organisms
using an “either/or” process
• “Di” meaning two “chotomous” meaning
branching
• Start by breaking organisms into two
groups, then two more, then two more, etc
Dichotomous Key
• Try this one:
1a. Organism walks on all 4 legs (quadruped)
2
1b. Organism walks on 2 legs (biped)
8
2a. Organism has visible fur
3
2b. Organism has no visible fur
20
3a. Organism lives in warm climates
7
3b. Organism lives in cold climates
4
4a. Organism has brown or black fur
Ursus americanus
4b. Organism has white fur
Ursus maritimus
Note Guide
•
Who was Linnaeus?
•
What are taxa?
•
•
The old classification system is:
The new classification system choices are:
– 1.
– 2.
How are organisms scientifically named?
What is the difference between the 3 domains?
– 1.
– 2.
– 3.
Name and describe the differences between the 4 kingdoms in Eukarya:
– 1.
– 2.
– 3.
– 4.
•
•
•
Note Guide (pg. 2)
•
•
Name and describe (or give an example of) each of the 10 phyla in Animalia:
– 1.
– 2.
– 3.
– 4.
– 5.
– 6.
– 7.
– 8.
– 9.
– 10.
How would you fully classify a human?
•
•
What is the purpose of a dichotomous key?
How do you read a dichotomous key?