Taxonomy
I.
II.
Taxonomy
Definition: The study of classification
A. Why group things?
1. Easier to find information about an organism
2. Easier to identify an organism
3. Shows evolutionary relationships
Historical Background
A. Aristotle - (350 B.C.) First scientist to group
organisms as either plants or animals
B.
Carolus Linnaeus (Karl Linne 1701-1778)
“Father of Modern Taxonomy”
1. Grouped organisms according to their structural
similarities
2. Developed a “Binomial Nomenclature” system for
identifying every organism
Binomial = two word
Nomenclature = naming system
III. Binomial Nomenclature Rules
A. Names are in Latin
 Why?
B. First name is the Genus, the second name is the species
C. Genus is Capitalized and species is not.
D. Both names are either italicized or underlined
e.g. Canis familiarus and Homo sapien
IV. Modern Taxonomy
A.
We still look at structural similarities, but we also
look at:
1.
Homologous structures - suggests common ancestor
2.
Developmental stages - from embryo to adult; the
more similar the stages, the closer they are
taxonomically
3.
DNA Evidence – shows how closely species are
related to each other and their taxonomic
relationship
What is the closest terrestrial relative of the whale?
Classification Categories (taxa)
V.
A.
B.
Different levels from the most general characteristics
to more specific characteristics
Eight levels of taxonomy are:
Domain Eukarya
Kingdom Animalia
Phylum Chordata
Class Mammalia
Order Primata
Family
Homideae
Genus Homo
Species sapien
Three Domains (developed in 1990)
A. Archaea- Kingdom Archaebacteria
B. Bacteria- Kingdom Eubacteria
C. Eukarya- Kingdoms Protista, Fungi, Plantae and
Animalia
VII. Six Kingdoms
A. Kingdom Archaebacteria (archae =“ancient”)
VI.
1.
2.
Prokaroytes, no nucleus, unicellular, autotroph or heterotroph
Ex: Extremophiles (bacteria that live in extreme places)
B.
Kingdom Eubacteria
1.
Prokaroytes, no nucleus, unicellular, autotroph or
heterotroph
2.
Ex: Streptococcus and E. coli, (“germs”)
C. Kingdom Protista
1. Simple, many are unicellular, no specialization of tissues
Protozoans
Algae
D.
Kingdom Fungi
1. Multicellular organisms that have a cell wall and
absorb food through the cell wall.
2. Ex: mushrooms, molds and yeast
E. Kingdom Plantae
1. Multicellular organisms, contain chlorophyll, have organs and
tissues, autotrophs
F. Kingdom Animalia
1. Multicellular organisms, heterotrophs, have organs and tissues
Classification Movie