Download Taxonomy Reflects Evolutionary History

Taxonomy Reflects
Evolutionary History
Section 15.4
Classification/Taxonomy
Classification the grouping of objects
for practical purposes.
 Ex:
 Taxonomy the identification, naming
and classification of species. The
science of classification of organisms

Aristotle(384-322 BC)
One of the earliest taxonomists
 Living things two groups Plants &
Animals
 Plants herbs, shrubs, and trees
 Animals live on land , water and air
**artificial system didn’t work, birds live
on land, water & air **
Listed 500 species, today  at least 5
million of which only 1.5 have been named

Carolus Linnaeus(1707-1778)




Developed a method still used today
Selected characteristics that led to more
natural groupings of species
Identified species by two names genus &
species Binomial nomenclature
The system also groups organisms into
different categories starting from the
smallest- species to the largest-kingdom
Classification Categories
Kingdom broadest
 Phylum
 Class
 Order
 Family
 Genus
 Species most specific

Classification-Dichotomous
Key

Series of paired statements that
describe the presence or absence of
certain characteristics
1 2
Animals
(1-4)
3
4
No wings(4)
No Feathers (3)
Wings(1-3)
Black & white(1)
Feathers (1,2)
Pink (2)
Phylogenetic Tree
A diagram that reflects the
evolutionary relationship between
species
 Each branch point represents a common
ancestor.

Phylogenetic Tree
Clade/ Cladistics
Clade Each
evolutionary branch in
a phylogenetic tree.
 Cladisticsthe
method used to
determine the
sequence of
branching in a
phylogenetic tree

Cladograms
A
phylogenetic diagram that
specifies the derived characters of
clades
Comparing Classification Schemes
Linnaeus two kingdom system, system
prevailed for 200 yrs
 Whittaker(1969) Five Kingdom system

Three Domains
 Reevaluation
of the fivekingdom system  three domain
system
2 Domains of Prokaryotes

Bacteria, Archaea
1 Domain of Eukaryotes

Eukarya