classification. what does classification mean? write your answer using a complete sentence
TRANSCRIPT
Classification
What does classification mean?
Write your answer using a complete sentence.
What is Classification?
It is the arrangement ofobjects, ideas, or information
into groups by finding common
traits or characteristics.
Purpose of Classification
• The reason is to logically organize the approximately 1.5 million species that we have on earth.
• The classification of these species is based on their DNA component, development, reproduction, morphology and physiology.
The History of Organization
Aristotle 384-322 BCEInterested in biological classification.
Patterns in nature.
Carl Linnaeus1707-1778 CE
Father ofBiological
Classification!
Binomial Nomenclature
• Carolus Linneaus developed a two-word naming system called binomial nomenclature.
• The system involves the assigning of a two-part scientific name to each species.
Binomial Nomenclature
• The two-part scientific name consist of the name of the genus [ the first one] and the name of the specific epithet [the second one].
• Both are underlined when written or in italics when typed.
Two-part Scientific Name
• The first is capitalized and the second in lower case. The two make up the name of the species.
• Examples: Homo sapiens, Drosophila melanogaster
• Sometimes, the first name may be abbreviated (ex. Escherichia coli could be written as E. coli)
Common name: Black and Polar Bear
Ursus americanus
Ursus maritimus
Why Latin is used in naming species?
i. Common names are not universal and meanings of words change over time
– “Possums” in America are NOT possums in Australia (Didelphis virginiana versus Trichosurus vulpecula)
Ii Latin is used because is it universally understood and being a “dead language” it will not change over time.
The Science of Classification
Scientist who classify or organize organisms (animals and plants) into related groups are called taxonomists.
Taxonomist study taxonomy and the
groupings are called “taxa”
Table Talk/Discussion Session
(1) Who was Carolus Linneaus?
(2) Explain what is meant by binomial nomenclature [ give an example]
(3) Why is Latin used in naming species?
Groups are also arranged in hierarchical order.
Linnaeus Hierarchical System of Classification
Largest to Smallest: Taxonomic categories
Domain
Kingdom (big)
Phylum
Class
Order
Family
Genus
species
Mnemonic Device
In the margin of your paper, create your own sentence to help you remember the order of
classification.
Dear King Philip Came Over For Good spaghetti
Dracula Kills People’s Children On Fridays, Get scared!
TaxonomyGrizzly bear Black bear Giant
pandaRed fox Albert
squirrelCoral snake
Sea star
KINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
SPECIES Ursus arctos Most specific
Least specific
Most specific
Least specific
New Discoveries
Questions
How can you answer these questions?
Why is Taxonomy Important?
Unknown species discovered.
New fossil Uncovered.
Cladograms/ Phylogenetic Trees
a. They are diagrams showing evolutionary relationships (family tree of species)
b. Constructed using morphology and DNA evidence to order the organisms in sequence.
Cladograms/ Phylogenetic Trees
c. Important features:i. Derived characteristics- recently evolved
characteristics of organisms being compared
ii. Ancestral characteristics- shared characteristics of all the organisms being compared