Classifying Living Things
Chapter 2
Why Classify?
Quiz 2A
Classify
to arrange things into groups
Classification:
the process of
grouping things
based on their
similarities
Taxonomy
(from Gk. taxis –
arrangement, order)
the science of classifying organisms
into groups
How does a good classification
system help?
•
Generalization: by learning
about individual’s you may also
learn about the whole group.
• It makes information about
specific organisms easier to
organize and find.
The Classification Hierarchy
First recorded
classification of
organisms was
attempted by Aristotle
the Greek scientist and
philosopher.
Aristotle’s Classification System
Plants
HERBS - if they lacked woody parts
SHRUBS - if they had several short
woody stems
TREES - one large woody stem .
Aristotle’s Classification System
Aristotle’s Classification System
Animals
FISH – swim
BIRDS - fly
LAND ANIMALS - walk
artificial classification system
based on appearance
(physical characteristics)
Aristotle's system was used for
approximately 2,000 years.
(used into the 1600’s)
Carolus Linnaeus
In the 1700's Carolus
Linnaeus, a Swedishnaturalist, discovered
problems in the
systematic arrangement
for botany and began to
sketch his own
classification method.
Carolus Linnaeus set forth a new
classification system in his works
(books he wrote).
• Species Plantarum
• Systema Naturae
Species Plantarum
• published 1753
• forms the basis
for plant
classification
Systema Naturae
• published 1758
• forms the basis
for animal
classification
Carolus Linnaeus
Linnaeus is known
as the father of
modern biological
classification or the
father of
taxonomy.
Carolus Linnaeus
Linnaeus also established the modern scientific
method of naming plants and animals.
His system is also an artificial classification
system (based on physical characteristics).
It has more flexibility than the previous systems.
It is still used today.
Linnaeus's 7 Basic Levels of Classification
His system has 7 basic levels (largest --->smallest)
kingdom
phylum (division)
class
order
family
genus
species
Species are often divided into sub-species (or varieties – like
dogs). Subphyla & subclasses may also be used.
The more
classification levels
that two organisms
share, the more
characteristics they
have in common.
As you move down
the levels there are
fewer kinds of
organisms in each
group.
Levels of Classification
Some
classification
systems have
an eighth level
– domain –
that is a level
higher than
kingdom.
Organisms are placed into domains and
kingdoms based on their cell type, their
ability to make food, and the number of cells
in their bodies.
Unicellular prokaryotes
The "true bacteria". Examples: Enteric bacteria
like E. coli, Salmonella typhus, Legionella,
Heliobacter pylorii (cause of many ulcers),
Neisseria gonorrhea (cause of gonorrhea),
Nitrogen-fixing bacteria that are able to convert
nitrogen gas into ammonia. Clostridium
(tetanus, botulism).
also unicellular prokaryotes but they are
found in some of the most extreme
environments on Earth (such as hot
springs, very salty water, swamps, volcano
vents in the Pacific Ocean floor, and the
intestines of cows)
Protist
Fungi
Animal
Plant
The Six Kingdoms
Kingdom Archaebacteria
Kingdom Eubacteria
Kingdom Protista
Kingdom Fungi
Kingdom Plantae
Kingdom Animalia
What about Humans?
Man is not an
animal; he is
God’s highest
creation and
created in God’s
image.
Christian Classification System?
Why don’t Christians invent a
“Christian Classification System” that
would not be influenced by
evolutionary bias? Any new system
that uses physical characteristics as the
basis for classification would likely
group organisms quite similarly to the
current system.
Christian Classification System?
There is a Christian classification system
that has been proposed called
baraminology. The term baraminology
comes from the Hebrew words bara,
meaning “create,” and min, meaning
“kind.” Baraminology attempts to classify
organisms according to their biblical kind.
Christian Classification System?
Since one of the primary functions of a
classification system is to eliminate confusion
regarding organisms, having a separate system
that is similar but not really parallel would likely
add confusion rather than eliminate it. A more
reasonable solution is for Christians to accept
the Bible as the source of all truth and reject any
evolutionary bias found in the current system..