Classification
Chapter 17
Finding Order in Diversity

taxonomy: the science of classifying living things

Carolus Linnaeus: developed current system of
naming and classifying organisms;
7 levels*largest group down to the individual*
Kingdom
Phylum
Class
Order
Family
Genus
Species
(King Phillip Came Over For Green Spaghetti)
Diversity, continued

binomial nomenclature: 2-word scientific
name given to each unique organism; first word
is general description-the genus; second word
identifies the specific organism-the species

the scientific name is always in Latin; the genus
is always capitalized; the species always
lowercase; both always underlined or in italics
Linnaeus’s System
KINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
Ursus arctos
SPECIES Ursus arctos
Testudo elephantopus
Carcharodon carcharias
Panthera tigris
Canis familiaris
Modern Evolutionary Classification

phylogeny: the study of evolutionary relationships
among organisms

organisms were originally grouped according to
their visible similarities/differences-----now grouped based on their evolutionary history in
addition to their similarities/differences
(evolutionary classification)
Cladogram


a diagram that shows the
evolutionary relationships
among a group of
organisms; a type of
evolutionary family tree
uses derived characters
(characteristics that only
appear in recent parts of
an organism’s lineage,
not in it’s older members)
Crustaceans
Gastropod
Barnacle
Limpet
Molted
exoskeleton
Tiny free-swimming larva
CLADOGRAM
Kingdoms - Then and Now

1700’s—Linnaeus—2 kingdoms—
Plantae and Animalia

late 1800’s—Protista (microorganisms), Plantae,
Animalia

1950’s—Monera, Protista, Fungi, Plantae,
Animalia (until this time, Fungi was
considered part of the Plantae kingdom)

1990’s—Eubacteria, Archaebacteria, Protista,
Fungi, Plantae, Animalia
The Three-Domain System

3 domains and 6 kingdoms:
1)domain Bacteria includes kingdom Eubacteria
2)domain Archaea includes kingdom
Archaebacteria
3)domain Eukarya includes kingdoms Protista,
Fungi, Plantae, and Animalia
Domains/Kingdoms, continued

members based on key characteristics:
1) cell type (prokaryote/eukaryote)
2) cell structures (cell walls/chloroplasts)
3) number of cells (unicellular/multicellular)
4) mode of nutrition (autotroph/heterotroph)
Eubacteria

domain Bacteria;
ecologically diverse
1) prokaryote
2) cell walls
containing
peptidoglycan
3) unicellular
4) autotroph or
heterotroph
Streptococcus
Escherichia coli
Archaebacteria

domain Archaea;
live in harsh environments
1) prokaryote
2) cell walls without
peptidoglycan
3) unicellular
4) autotroph or
heterotroph
Aquifex aeolicus
Methanobacterium formicum
Protista

Paramecium bursaria
Fuligo septica
domain Eukarya;
“catch-all” kingdom
1) eukaryote
2) cell walls ocellulose in
some; some have
chloroplasts
3) most unicellular, some
colonial, some
multicellular
4) autotroph or
heterotroph
Fungi

Auricularia auricula-judae
Trichophyton rubrum
domain Eukarya; feed
on dead and decaying
matter
1) eukaryote
2) cell walls made of
chitin
3) most multicellular;
some unicellular
4) heterotroph
Plantae

Domain Eukarya; are
nonmotile (cannot
move
from place to place)
1) eukaryote
2) cell walls of
cellulose;
have chloroplasts
3) multicellular
4) autotroph
Lupinus arcticus
Sequoia sempervirens
Animalia

domain Eukarya;
many species exist in
nearly every part of
the planet
1) eukaryote
2) no cell walls or
chloroplasts
3) multicellular
4) heterotroph
Desmodus rotundus
Agalychnis callidryas