Taxonomy &
Classification
Classification: The process of putting similar things into groups.
Taxonomy: Is the science of classifying organisms.
History of Classification

4000 B.C.
Aristotle (Greek Philosopher)
Created first written classification scheme
 TWO Groups - Plants & Animals
 Animal group - anything that lived on land, in the
water or in the air.
 Plant group - based this on their different stems
1500's - 1700's
o Many different classification systems created
 Many of them really complicated
 Names based on common names - This created confusion
 Names also based on long scientific definitions
o
o


1700's - Carols Linnaeus - Swedish Biologist
o established a simple system for classifying and naming
organisms
o Based on structural similarities of organism
o Binomial Nomenclature - 2 name naming system - still in use
today.
o Created a system of groups called TAXA or TAXON
o Each Taxon is a category into which related organisms are
placed
 Approximantly 2.5 million kinds of organisms identified
Modern Day Levels of Classification
Kingdom
Kids
Phylum
Playing
Kingdom
Phylum/Division
Class
Order
Family
Genus
Species
Class
Order
Catch
On
Family
Genus
Freeways
Get
Species
Squashed
Man
Animalia
Box Elder Tree
Plantae
Bobcat
Animalia
Canadian lynx
Animalia
Chordata
Anthophyta
Chordata
Chordata
Mammalian Dicotyledonae
Mammalia Mammalia
Primates
Sapindales
Carnivora
Carnivora
Hominidae
Aceracae
Felidae
Felidae
Homo
Acer
Lynx
Lynx
sapiens
nugundo
rufus
canadensis
Modern Taxonomy
The Evidence used to classify into taxon groups
1) Embryology
2) Chromosomes / DNA
3) Biochemistry
4) Physiology
5) Evolution
6) Behavior
Binomial Nomenclature
Is a system of Scientific Naming using TWO NAMES FOR EVERY ORGANISM:
The GENUS and the SPECIES name.
The system follows certain rules:
1. The scientific name must be in Latin.
This helps to communicate accurate information and overcome language
barriers since biologists around the world speak many different languages.
Latin is useful because it is a “dead” language, meaning it is no longer spoken
and as a result never changes. Every organism is assigned a unique two-word
scientific name to each organism. (THE TWO-WORD NAMING SYSTEM IS
CALLED BINOMIAL NOMENCLATURE)
2. The first part of an organism’s scientific name is its Genus and the second
part of the name is its species. (Ex. Homo sapiens: Homo is the genus
humans belong to, and sapiens is our species.)
3. The Genus name refers to the relatively small group of related organisms to
which a particular type of organism belongs.
4. SPECIES means IDENTIFIER in Latin. The Species name is usually a Latin
description of some important characteristic of the organism. A species can
contain ONLY ONE TYPE OF ORGANISM.
5. For a scientific name to be written correctly, the genus should be capitalized,
the species should be in lowercase. If typewritten, both should be italicized.
If handwritten, both the genus and the species should be underlined.
**IDENTIFYING ORGANISMS BY THEIR GENUS AND SPECIES NAMES
IS CALLED
BINOMIAL NOMENCLATURE. ("TWO-NAME NAMING)
*Advantages of using a universal taxonomic system:
1. Organization: Groups similar organisms together
2. Common Language: No misunderstandings based on language because all
scientists converse in Latin.
3. Economics: No need to translate from language. All things can be
published in Latin.
Phylogeny
Classification of organisms based on evolutionary relationships
Allow us to construct s Phylogenic tree (Family Tree)
More closely related organisms share branches of the tree. Less related
organisms are located on different branches.
Five-Kingdom System
Evolved from Aristotle's 2 Kingdoms
to the Present day 5 Kingdoms (Actually Six Kingdoms.
There is no longer a Kingdom Monera)
The Kingdom formerly known as Monera has been
further divided into Kingdom Archea (ancient bacteria)
and Kingdom Bacteria (true bacteria).
Characteristics of the Kingdom Archeabacteria and Eubacteria:
1. All are prokaryotes
2. Some are heterotrophic (most eubacteria)and some are autotrophic
(Archeabacteria)
(Heterotrophic - Organism that can't synthesize (make) it's own
food)
(Autotrophic - Organism that CAN make it's own food –
photosynthesis or chemosynthesis)
3. Some are anaerobic and some are aerobic
4. Can be aquatic, terrestrial and/or live in the air
5. mostly asexual reproduction
6. mostly non motile (1 form does move)
Kingdom Protista
Characteristics of the Protista Kingdom
1.
2.
3.
4.
5.
6.
All are eukaryotes
Can be either heterotrophic or autotrophic
Unicellular or colonial (there is one protest that is multicellular)
Mostly aquatic
Mostly asexual reproduction
Both motile and nonmotile
Things like: Protozoa (animal-like protists(heterotrophs)), slime molds
(fungal protists (heterotrophs)) and algae (plant-like
protists(autotrophs)).
Kingdom Fungi
Characteristics of the Fungi Kingdom
1.
2.
3.
4.
5.
6.
All are eukaryotes
Absorptive Heterotrophs (digest food outside their bodies)
Multicellular
Mostly terrestrial
asexual and sexual
nonmotile
Things like: Mushrooms, bread molds, water molds, yeasts, rusts,
puffballs
Kingdom Plantae
Characteristics of Plantae Kingdom
1.
2.
3.
4.
5.
6.
All are eukaryotes
Multicellular
Autotrophic
Mostly Terrestrial
Asexual and Sexual
Nonmotile
Things like: mosses, ferns, conifers, and flowering plants
Kingdom Animalia
Characteristics of Animalia Kingdom
1.
2.
3.
4.
5.
6.
All are eukaryotes
Multicellular
Ingestive Heterotrophs (digest food inside their bodies)
Terrestrial and Aquatic
Sexual ( a few asexual)
Motile ( a few are nonmotile)
Things like: sponges, jellyfish, mollusks, round worms, flat worms,
segmented worms, arthropods, starfish, fish, amphibians, reptiles, birds,
mammals