Transcript Evolution and the History of Life

Natural Selection
Part 2
MLK
Spring 2006
M.Elizabeth
www.marric.us/teaching
Chapter 10: Classification
I.
Chapter 10.1: Sorting it all out
Classification is the arrangement of
organisms into orderly groups based on
their similarities.
A. Why Classify
It is a natural thing for humans to
classify things so that we know how
best to use them
Why Classify
• Biologist classify organisms living and
extinct in order to make sense because
there are so many different kinds of
organisms.
Geologists have done the same by putting rocks into
categories: sedimentary, igneous, and metamorphic.
Biologist Classify
• Classifying living things makes it easier
for biologists to see patterns and to
find answers to the following questions
– How many known species are there
– What are the characteristics of
these species
– What are the relationships between
these species
B. Levels of Classification
• Six Kingdoms each of which are divided
into phyla (phylum singular).
• Each phylum is divided into classes.
• Each class is divided into orders
• Each order is divided into families
• Each family is divided into genera (genus
singular)
• Each genus is divided into species.
• A species is a group of individuals that can
mate and produce fertile offspring.
Mnemonic - Rhyme
•
•
•
•
•
•
•
•
King Phillip Came Over For Grape Soda
King = Kingdom
Phillip = Phyla
Came = Class
Over = Order
For = Family
Grape = Genus
Soda = Species
Kingdoms have the
most members and
the classification
system narrows the
numbers to species
which has one
(even now
sometimes scientist
narrow to the
subspecies - strains
C. What is the basis for Classification
• Carolus Linnaeus is the “father” of
taxonomy.
• Taxonomy is the science of identifying,
classifying, and naming living things.
• Linnaeus was a Swedish physician and
botanist who lived in the 1700’s
• Linnaeus classified organism by their
shared characteristics
• After Darwin – scientist looked also for
presumed evolutionary relationships
Cladogram – branching diagram
D. Naming Names
• Linnaeus as father of taxonomy developed
the two part scientific name for species.
• Latin or Greek names are used as building
blocks for scientific names
• The first person to discover a species is
given the opportunity to name it
• The two part scientific name begins with
the genus and is followed by the species.
Both are underlined or italicized.
E. Dichotomous Keys
• Taxonomists use guides known as
dichotomous keys to aid in identifying
unknown organisms.
• A Dichotomous key consits of several
pairs of descriptive statements that have
an either/or response.
1.
2.
3.
4.
5.
6.
10.2 The Six Kingdoms
Protista (eukaryotic cells with characteristics
like animal and plant)
Archaebacteria – prokaryotic cells that live in
extreme environments
Eubacteria – prokaryotic cells that live
everywhere except extreme environments.
Plantae – eukaryotic cells (plant cells) oldest
living organisms
Fungi – eukaryotic cells like plants but do not
perform photosynthesis
Animalia – eukaryotic cells, can move, have
nervous systems