Natural Selection Natural Selection Part 2Part 2

MLKMLKSpring 2006Spring 2006

M.ElizabethM.Elizabethwww.marric.us/teachingwww.marric.us/teaching

Chapter 10: ClassificationChapter 10: Classification

I. Chapter 10.1: Sorting it all outClassification is the arrangement of organisms into orderly groups based on their similarities.

A. Why ClassifyIt is a natural thing for humans to classify things so that we know how best to use them

Why ClassifyWhy 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 ClassifyBiologist 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 ClassificationB. 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 - RhymeMnemonic - 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 ClassificationC. 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 diagramCladogram – branching diagram

D. Naming NamesD. 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 KeysE. 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.

10.2 The Six Kingdoms10.2 The Six Kingdoms1. Protista (eukaryotic cells with

characteristics like animal and plant)2. Archaebacteria – prokaryotic cells that live

in extreme environments3. Eubacteria – prokaryotic cells that live

everywhere except extreme environments.4. Plantae – eukaryotic cells (plant cells)

oldest living organisms5. Fungi – eukaryotic cells like plants but do

not perform photosynthesis6. Animalia – eukaryotic cells, can move, have

nervous systems