Classifying

Organism

sUnit 1 Lesson 2

• What methods are used to classify living things into groups?

• Why does every species have a scientific name?

Classifying Organisms

Classifyto arrange things into groups

Classification: the process of

grouping things based on their

similarities

Taxonomy

the science of classifying organisms into groups

(from Gk. taxis –

arrangement, order)

Two types of objects

Animate: “possessing life”

Inanimate: “not living”

• There have been many different ideas about how to organize, or classify, living things.

• Aristole classified organisms into two main groups: plants & animals

• Carolus Linnaeus classified organisms into two main groups, called kingdoms, based on similar structures.

Classifying Living Things

What evidence is used to classify living things into groups?

· Cell type, complex or simple· Their ability to make food· The number of cells in their body

• The current classification method for organisms is called systematics.

• Systematics uses all known evidence to classify organisms, including cell type, how food and energy are obtained, structure and function of features, common ancestry, and molecular analysis.

Classifying Living Things

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 .

Animals

FISH – swim

BIRDS - fly

LAND ANIMALS - walk

Aristotle’s Classification System

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 Swedish-naturalist, 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 1753

• forms the basis for plant classification

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.

Carolus Linnaeus

Linnaeus's 7 Basic Levels of Classification

His system has 7 basic levels (largest --->smallest)

Species are often divided into sub-species (or varieties – like dogs). Subphyla & subclasses may also be used.

kingdom

phylum (division)

class

order

family

genus

species

kingdomScience Use a classification category that ranks above phylum and below domainCommon Use a territory ruled by a king or a queen

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.

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.

Levels of Classification

Some classification systems have

an eighth level – domain –

that is a level higher than kingdom.

Levels of Classification Organisms are now classified into

one of three domains and then into one of six kingdoms.

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)

Fungi

Protist

Plant

Animal

The Six Kingdoms

Kingdom Archaebacteria

Kingdom Eubacteria

Kingdom Protista

Kingdom Fungi

Kingdom Plantae

Kingdom Animalia

Kingdom ArchaebacteriaIn 1983, scientists tool samples from a spot deep in the Pacific Ocean where hot gases and molten rock boiled into the ocean form the Earth’s interior. To their surprise they discovered unicellular (one cell) organisms in the samples. These organisms are today classified in the kingdom, Archaebacteria.

Archaebacteria are found in extreme environments such as hot boiling water and thermal vents under conditions with no oxygen or highly acid environments.

Kingdom EubacteriaLike archaebacteria, eubacteria are complex and single celled. Most bacteria are in the EUBACTERIA kingdom. They are the kinds found everywhere and are the ones people are most familiar with. Eubacteria are classified in their own kingdom because their chemical makeup is different.

Most eubacteria are helpful. Some produce vitamins and foods like yogurt. However,

some eubacteria, Streptococci, can give you strep throat!

Kingdom ProtistaSlime molds and algae are protists. Sometimes they are called the odds and ends kingdom because its members are so different from one another. Protists include all microscopic organisms that are not bacteria, not animals, not plants and not fungi.

Most protists are unicellular. You may be wondering why those protists are not classified in the Archaebacteria or Eubacteria kingdoms. It is because, unlike bacteria, protists are complex cells.

Kingdom Fungi

Mushrooms, mold and mildew are all

examples of organisms in the kingdom fungi.

Most fungi are multicellular and consists of many

complex cells.

Fungi are organisms that biologists once confused with plants, however, unlike plants, fungi cannot make their own food. Most obtain their food from parts of plants that are decaying in the soil.

Kingdom PlantaeYou are probably quite familiar with the members of this kingdom as it contains all the plants that you have come to know - flowering plants, mosses, and ferns. Plants are all multicellular and consist of complex cells.

With over 250,000 species, the plant kingdom is the second largest kingdom. Plant species range from the tiny green mosses to giant trees.

Plants are autotrophs, organisms that make their own food.

Kingdom AnimaliaAll animals consist of many complex cells. They are also heterotrophs. Members of the animal kingdom are found in the most diverse environments in the world

The animal kingdom is the largest kingdom with over 1 million known species.

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..