Classifying OrganismsClassifying Organisms

Chapter 3 Section 1Chapter 3 Section 1

Why do Scientists Classify?Why do Scientists Classify?

Imagine a grocery store…Imagine a grocery store…

How are they organized?How are they organized?

What would happen if they were not What would happen if they were not organized?organized?

How is your life organized?How is your life organized?

Why do Scientists Classify?Why do Scientists Classify?

Almost 2 million kinds of organisms on Almost 2 million kinds of organisms on EarthEarth

Need to keep organized! (Easier to Need to keep organized! (Easier to study!)study!)

ClassificationClassification

= process of grouping things based on = process of grouping things based on their similaritiestheir similarities

Why do Scientists Classify?Why do Scientists Classify?

TaxonomyTaxonomy

=scientific study of how living things =scientific study of how living things are classifiedare classified

Useful because:Useful because:

once classified, scientists will know a once classified, scientists will know a lot about an organismlot about an organism

Early Classification SystemsEarly Classification Systems

Aristotle (4Aristotle (4thth century B.C.) century B.C.)

-observed animals-observed animals

-watched appearance, behavior, -watched appearance, behavior, movementmovement

-fly, swim, and walk/crawl/run-fly, swim, and walk/crawl/run

-observed similarities and differences-observed similarities and differences

-used differences to divide into -used differences to divide into smaller smaller subgroupssubgroups

1707-1778

LinnaeusLinnaeus

Carolus Linnaeus (1750s)Carolus Linnaeus (1750s)

-used observations as basis of his -used observations as basis of his systemsystem

-placed organisms based on -placed organisms based on observable featuresobservable features

Devised naming system for organisms:Devised naming system for organisms:

Binomial NomenclatureBinomial Nomenclature

LinnaeusLinnaeus

Binomial NomenclatureBinomial Nomenclature=2 part naming system=2 part naming system-uses Latin words-uses Latin words

Genus speciesGenus species Felis concolorFelis concolorGenus is capitalized; species is NOT.Genus is capitalized; species is NOT.If you can’t italicize, If you can’t italicize, underlineunderline the the

genus and species!genus and species!

Classification TodayClassification Today

Species with similar evolutionary Species with similar evolutionary histories are classified more closely histories are classified more closely together.together.

-when organisms share a common -when organisms share a common ancestor, they share an evolutionary ancestor, they share an evolutionary historyhistory

6 Kingdoms6 Kingdoms

Archebacteria

Eubacteria

Domain ArchaeaDomain Archaea

Domain EubacteriaDomain Eubacteria

Domain EukaryaDomain Eukarya

Levels of ClassificationLevels of Classification

-based on contributions of both Aristotle -based on contributions of both Aristotle and Linnaeusand Linnaeus

There are There are 88 levels of classification. levels of classification.

Remember the first letter of this Remember the first letter of this sentence:sentence:

DDumbumb K Kids ids PPlay lay CCatch atch OOver ver FFarmer armer GGreen’s reen’s SShed.hed.

8 Levels of Classification8 Levels of Classification

DDomain omain broadest levelbroadest level

KKingdom ingdom

PPhylumhylum

CClasslass

OOrderrder

FFamilyamily

GGenus enus

SSpeciespecies most specificmost specific

Kingdom ProtistaKingdom Protista

Amoeba Paramecium

Giardia

Water Mold Slime Mold

Euglena Dinoflagellates

DiatomBrown Algae

Green Algae

Kingdom FungiKingdom Fungi

Kingdom PlantaeKingdom Plantae

Bryophyte (Moss)

Pteridophyte(Fern)

Pteridophyte(Fern)

Coniferophytes (Pine Trees) Angiosper

m; DicotAngiosper

m; Monocot

Human ClassificationHuman Classification

Using the Classification Using the Classification SystemSystem

Field guides help identify organisms.Field guides help identify organisms.

-they highlight differences between -they highlight differences between similar organisms (like trees)similar organisms (like trees)

Taxonomic Key (AKA Dichotomous Key)Taxonomic Key (AKA Dichotomous Key)

-paired statements that describe the -paired statements that describe the physical characteristics of different physical characteristics of different organismsorganisms

http://www.goldiesroom.org/Multimedia/Bio_Images/02%20Classification/03%20Classification%20of%20a%20Species.jpghttp://www.goldiesroom.org/Multimedia/Bio_Images/02%20Classification/03%20Classification%20of%20a%20Species.jpg

Taxonomic KeyTaxonomic Key 1. Fruits occur singly ....................................................... Go 1. Fruits occur singly ....................................................... Go

to 3to 3 1' Fruits occur in clusters of two or more ......................... Go 1' Fruits occur in clusters of two or more ......................... Go

to 2to 2 2. Fruits are round ....................................................... 2. Fruits are round .......................................................

GrapesGrapes 2' Fruits are elongate ................................................... 2' Fruits are elongate ...................................................

BananasBananas 3. Thick skin that separates easily from 3. Thick skin that separates easily from

flesh .............Orangesflesh .............Oranges 3' Thin skin that adheres to flesh .............................. Go to 43' Thin skin that adheres to flesh .............................. Go to 4 4. More than one seed per fruit ............................ Apples4. More than one seed per fruit ............................ Apples 4' One seed per fruit ............................................ Go to 54' One seed per fruit ............................................ Go to 5 5. Skin covered with velvety hairs .................... Peaches5. Skin covered with velvety hairs .................... Peaches 5' Skin smooth, without hairs ........................... Plums5' Skin smooth, without hairs ........................... Plums

Dichotomous KeysDichotomous Keys

1a. Organism has 4 legs Go to # 2

1b. Organism has more than 4 legs Go to # 20

2a. Organism has a tail Go to # 3

2b. Organism has no tail Go to # 35

3a. Organism has stripes Bengal Tiger

3b. Organism has no stripes African Lion

Dichotomous KeyDichotomous Key Try this one:Try this one:

1a. Organism walks on all 4 legs (quadruped)2

1b. Organism walks on 2 legs (biped)8

2a. Organism has visible fur 3

2b. Organism has no visible fur20

3a. Organism lives in warm climates7

3b. Organism lives in cold climates 4

4a. Organism has brown or black fur Ursus americanus

4b. Organism has white fur Ursus maritimus

Note GuideNote Guide Who was Linnaeus?Who was Linnaeus?

What are taxa?What are taxa?

How are organisms scientifically named? How are organisms scientifically named? What is the difference between the 3 domains?What is the difference between the 3 domains?

– 1.1.– 2.2.– 3.3.

Name and describe the differences between the 4 kingdoms in Eukarya:Name and describe the differences between the 4 kingdoms in Eukarya:– 1.1.– 2.2.– 3. 3. – 4.4.

Note Guide (pg. 2)Note Guide (pg. 2)

Name and describe (or give an example of) each of the 10 phyla in Animalia:Name and describe (or give an example of) each of the 10 phyla in Animalia:– 1.1.– 2.2.– 3. 3. – 4. 4. – 5.5.– 6.6.– 7.7.– 8.8.– 9.9.– 10.10.

How would you fully classify a human?How would you fully classify a human?

What is the purpose of a dichotomous key?What is the purpose of a dichotomous key? How do you read a dichotomous key?How do you read a dichotomous key?