TaxonomyTaxonomy“The Study of “The Study of Classification”Classification”

What do you think?What do you think?

What does classification mean?What does classification mean?

Why is classification important?Why is classification important?

When do we use classification systems in When do we use classification systems in our everyday lives?our everyday lives?

Books at the library, iPods and movies, even people!

ObjectivesObjectives

Learn about the history of classification Learn about the history of classification systemssystems

Recognize Linnaeus’ contribution Recognize Linnaeus’ contribution Discuss classification keys and their Discuss classification keys and their

usefulnessusefulnessStudy Phylogenic trees and CladogramsStudy Phylogenic trees and CladogramsOutline the 6 Kingdom system Outline the 6 Kingdom system

What exactly is What exactly is classification?classification?

Classification is a branch of Biology Classification is a branch of Biology called called TTaxonomy. .

TaxonomyTaxonomy classifies based on similarities classifies based on similarities

……but it wasn’t always this way!but it wasn’t always this way!

Meet Aristotle (350 BC)Meet Aristotle (350 BC)

Aristotle classified all living Aristotle classified all living organisms as either a plant or organisms as either a plant or an animal. an animal.

He further classified animals by He further classified animals by where they lived, and plants by where they lived, and plants by their size.their size.

Aristotle’s Classification Aristotle’s Classification SchemeScheme

ALL LIVING ORGANISMSALL LIVING ORGANISMS

PLANTS ANIMALS

PLANTS

SHORT (Herbs) MEDIUM (Shrubs) TALL (Trees)

ANIMALS

LAND WATER AIR

What are some problems What are some problems with this classification with this classification

system?system?

Some animals live in more than one Some animals live in more than one habitat during their lives.habitat during their lives.

Most plants start small and grow larger.Most plants start small and grow larger.

These problems were These problems were recognized by recognized by

Carolus LinnaeusCarolus Linnaeus

“The Father of Modern Taxonomy”

Carolus Linnaeus Carolus Linnaeus

Linnaeus was a Swedish botanist who Linnaeus was a Swedish botanist who lived in the 18lived in the 18thth century. century.

He decided to classify organisms based He decided to classify organisms based on their visible similarities and on their visible similarities and differences in structure.differences in structure.

Carolus LinnaeusCarolus Linnaeus

Linnaeus made three huge contributions Linnaeus made three huge contributions to modern taxonomy:to modern taxonomy:

Using structural criteria for classificationUsing structural criteria for classification

Establishing the 7 taxa currently used.Establishing the 7 taxa currently used.

Created the Binomial NomenclatureCreated the Binomial Nomenclature

The 7 The 7 Taxa

KingdomKingdom PhylumPhylum ClassClass OrderOrder FamilyFamily GenusGenus SpeciesSpecies

Used in Scientific Names

Pneumonic Device:

KingPhillipCameOverForGinger Snaps

7 Taxa7 Taxa

Did you notice?Did you notice?

As you go down through the 7 taxa, you As you go down through the 7 taxa, you get more and more details about the get more and more details about the organism you are looking at.organism you are looking at.

Organisms get more and more similar Organisms get more and more similar from top to bottom.from top to bottom.

Let’s Classify Us! Let’s Classify Us!

Let’s classify a human:Let’s classify a human: Kingdom: Kingdom: AnimaliaAnimalia Phylum: ChordataPhylum: Chordata Class: Class: MammaliaMammalia Order: Order: PrimatesPrimates Family: Family: HominidaeHominidae Genus: Genus: HomoHomo Species: Species: SapiensSapiens

Binomial NomenclatureBinomial Nomenclature

Binomial nomenclature is a “two word” Binomial nomenclature is a “two word” naming system.naming system.

The first term describes the organisms The first term describes the organisms genusgenus while the second term describes while the second term describes the the speciesspecies..

Genus and SpeciesGenus and Species

Organisms placed in the same genus Organisms placed in the same genus have similar structures (look the same).have similar structures (look the same).

Organisms with the same species name Organisms with the same species name are so similar they would be able to are so similar they would be able to reproduce under normal circumstances reproduce under normal circumstances to produce to produce fertilefertile offspring. offspring.

Binomial NomenclatureBinomial Nomenclature

Scientific names are written in Latin and have Scientific names are written in Latin and have something to do with the organisms characteristics or something to do with the organisms characteristics or where they live. (where they live. (Castor canadensisCastor canadensis) () (Ursus horribilus)Ursus horribilus)

Scientific names are written in Scientific names are written in italicsitalics or or underlinedunderlined..

The first term is always capitalized while the second The first term is always capitalized while the second isn’tisn’t Example: Example: Homo sapiens Homo sapiens humanshumans Homo sapiensHomo sapiens H. sapiensH. sapiens

Examples of Scientific NamesExamples of Scientific Names

Canis lupusCanis lupus Wolf Wolf Canis familiarisCanis familiaris Dog Dog

These organisms are structurally similar These organisms are structurally similar (same genus) but different species (same genus) but different species (cannot reproduce under normal (cannot reproduce under normal circumstances to produce fertile circumstances to produce fertile offspring)offspring)

Scientific NamesScientific Names

Equus caballusEquus caballus - horse - horse Equus asinusEquus asinus – donkey – donkey

When a donkey and a horse reproduce, When a donkey and a horse reproduce, their offspring is a mule, which is sterile. their offspring is a mule, which is sterile. (1 in 100 000 will have an offspring)(1 in 100 000 will have an offspring)

Check out the Scientific Check out the Scientific NamesNames

KEY TERMSKEY TERMS

SYSTEMATICSSYSTEMATICS Scientific study of the diversity of organisms Scientific study of the diversity of organisms

and their natural and their natural (evolutionary) (evolutionary) relationshipsrelationships

A systematist seeks to reconstruct A systematist seeks to reconstruct phylogenyphylogeny

KEY TERMSKEY TERMS

PHYLOGENYPHYLOGENY Evolutionary historyEvolutionary history of a species or other of a species or other

taxonomic grouptaxonomic group

MONOPHYLETICMONOPHYLETIC Said of a group consisting of organisms that Said of a group consisting of organisms that

evolved from a evolved from a common ancestorcommon ancestor

KEY TERMSKEY TERMS

CLADISTICSCLADISTICS Classification of organisms based on Classification of organisms based on

recency of common ancestryrecency of common ancestry rather than rather than degree of structural similaritydegree of structural similarity

CladisticsCladistics

Cladists emphasize phylogeny by Cladists emphasize phylogeny by focusing on when focusing on when evolutionary lineagesevolutionary lineages (lines of descent) divide into two (lines of descent) divide into two branches branches

Cladists develop Cladists develop cladogramscladograms

KEY TERMSKEY TERMS

CLADOGRAMCLADOGRAM A A diagramdiagram that that illustratesillustrates evolutionaryevolutionary

relationshipsrelationships based on the principles of based on the principles of cladisticscladistics

Building a CladogramBuilding a Cladogram

Characters

TAXON

Moss

Fern

Pine

Daisy

VASCULAR TISSUES SEEDS FLOWERS

A

P

P

P P P

P

A A

A

A

A

Mo

ss

(a) All of the plant groups shown here except mosseshave vascular

Pin

e

Dai

sy

Fer

n

Node1

Common plantancestor

Common ancestorwith vascular tissues

Mo

ss

Pin

e

Dai

sy

Fer

n

Node1

Common plantancestor

Common ancestorwith vascular tissues

Node2

(b) Seeds are a shared character for all plant groupsshown here except mosses and ferns.

Mo

ss

Pin

e

Dai

sy

Fer

n

Node1

Common plantancestor

Common ancestorwith vascular tissues

Node2

Node3

Commonseed-producingancestor

(c) Of the plant groups shown here, only the daisyproduces flowers.