Download Classification of Life

Chapter 17
Organizing Life’s Diversity
Section 1
Classification
Classification
 The grouping of objects or
information based on similarities.
Taxonomy
 Branch of biology that groups and
names organisms based on studies of
their different characteristics.
Taxonomy
 Organisms are ranked in taxa.
 The broader the taxon, the more species
it contains.
 The smallest taxon is the species,
followed by the genus.
 The largest taxon is the domain.
Taxonomy
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Kids
Playing
Chase
On
Freeways
Get
Smooshed
Taxonomy
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Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Kingdoms
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Archaebacteria
Eubacteria
Protists
Fungi
Plants
Animals
 The kingdoms are divided mainly by
differences in cellular structure and
methods of obtaining energy
Binomial Nomenclature
 Modern classification scheme.
 Developed by Carolus Linnaeus
(1707-1778), a Swedish botanist.
 Based on physical and structural
similarities of organisms.
 Also shows the evolutionary history of
the organism.
Binomial Nomenclature
 Every organism is named using two
words.
 The first word identifies the genus.
 A genus consists of a group of similar
species.
 The second word is the specific
epithet.
 Describes a characteristic of the
organism.
Scientific Names
 Latin.
 The first letter of the genus name is
uppercase.
 The first letter of the specific epithet
is lowercase.
 Italicized in print.
 Underlined when handwritten.
Evolutionary Relationships
 Based on:
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Structural similarities.
Breeding behavior.
Geographical distribution.
Chromosome comparisons.
Biochemistry (such as DNA).
Phylogeny
 Evolutionary history of a species.
Cladistics
 Biological system of classification
based on phylogeny.
 Utilizes cladograms.
 Models of the phylogeny of a species
based on derived traits.
 Derived traits are unique inherited
characteristics kept by the species as it
diverged from common ancestral groups.
How to analyze a cladogram:
 Branches show proposed ancestry.
 Two groups on diverging branches
probably share a more recent
ancestor than those groups farther
away.