Classification. What does classification mean? Write your answer using a complete sentence

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