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December 2December 2

Warm upWarm upPass forward Chapter 17 Pass forward Chapter 17

packetpacketNotes over Ch. 18 - classificationNotes over Ch. 18 - classification

Practice Dichotomous Key Practice Dichotomous Key wksheetwksheet

HW- Alien Invasion Work HW- Alien Invasion Work SheetSheet

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•There are There are 13 billion13 billion known known species of organismsspecies of organisms

•This is This is only 5% of allonly 5% of all organisms that ever organisms that ever lived!!!!!lived!!!!!

•New organismsNew organisms are still are still being found and identifiedbeing found and identified

Species of OrganismsSpecies of Organisms

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What is Classification?What is Classification?

•To study the diversity of life, biologists use a classification system to name organisms and group them in a logical manner

•Taxonomy is the branch of biology that groups and names organisms based on studies of their different characteristics.

•Taxonomists Taxonomists are scientists are scientists that identify & name that identify & name organismsorganisms

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Benefits of ClassifyingBenefits of Classifying

•Accurately & uniformlyAccurately & uniformly names organisms names organisms

•Prevents Prevents misnomersmisnomers such such as starfish & jellyfish that as starfish & jellyfish that aren't really fish aren't really fish

•Uses Uses same language same language (Latin or some Greek)(Latin or some Greek) for for all names all names

Sea”horseSea”horse”??”??

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Confusion in Using Different Confusion in Using Different Languages for NamesLanguages for Names

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Latin Names are Understood Latin Names are Understood by all Taxonomistsby all Taxonomists

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Early TaxonomistsEarly Taxonomists

•2000 years ago, 2000 years ago, AristotleAristotle was the was the first taxonomistfirst taxonomist

•Aristotle divided Aristotle divided organisms into organisms into plants & animalsplants & animals

•He He subdividedsubdivided them by their them by their habitathabitat ---land, sea, ---land, sea, or air dwellers or air dwellers

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Early TaxonomistsEarly Taxonomists•John Ray, a John Ray, a

botanist,botanist, was was the first to use the first to use Latin for Latin for namingnaming

•His His namesnames were were very longvery long descriptions descriptions telling telling everything everything about the plantabout the plant

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Carolus LinnaeusCarolus Linnaeus1707 – 17781707 – 1778

•18th century taxonomist

•Classified organisms by their structure

•Developed naming system still used today

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Carolus LinnaeusCarolus Linnaeus

•Called the Called the “Father of “Father of Taxonomy”Taxonomy”

•Developed the modern Developed the modern system of naming system of naming known as known as binomial binomial nomenclaturenomenclature

•Two-wordTwo-word name (Genus name (Genus & species)& species)

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Standardized Standardized NamingNaming

•Binomial nomenclature Binomial nomenclature usedused

•Genus speciesGenus species Genus

Noun, Capitalized,

speciesDescriptive, Lower Case,

•Latin or GreekLatin or Greek

•ItalicizedItalicized in print in print

•Capitalize genusCapitalize genus, but , but NOT speciesNOT species

•UnderlineUnderline when writing when writing

Turdus Turdus migratoriusmigratorius

European European RobinRobin

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Binomial NomenclatureBinomial Nomenclature

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Classification GroupsClassification Groups

•TaxonTaxon ( ( taxataxa-plural) is a -plural) is a category into which related category into which related organisms are placedorganisms are placed

•There is a There is a hierarchyhierarchy of of groups (taxa) from broadest groups (taxa) from broadest to most specificto most specific

•Domain, Kingdom, Phylum, Domain, Kingdom, Phylum, Class, Order, Family, Class, Order, Family, Genus, Genus, speciesspecies

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Hierarchy-Taxonomic Hierarchy-Taxonomic GroupsGroups

DomainKingdom

Phylum (Division – used for plants)

Class Order Family

Genus Species

BROADEST BROADEST TAXONTAXON

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KKinging

PPhilliphillip

CCameame

OOverver

FForor

GGoodood

SSoup!oup!

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Evolutionary Classification

Phylogeny – evolutionary relationships among organisms

Evolutionary classification – strategy of grouping organisms together based on their evolutionary history

– Fossil record– Comparative homologies– Cladistics– Comparative sequencing of DNA/RNA among

organisms– Molecular clocks

Taxonomic Diagrams

Mammals Turtles Lizards and Snakes

Crocodiles Birds Mammals Turtles Lizards and Snakes

Crocodiles Birds

CladogramPhylogeneticTreePhylogenetic

Tree

Cladogram

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CladogramCladogramDiagram showing how organisms are related Diagram showing how organisms are related

based on based on shared, derived characteristicsshared, derived characteristics such as feathers, hair, or scalessuch as feathers, hair, or scales

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Primate Primate CladogramCladogram

Further Classification

DomainMost inclusive category Larger than a kingdom

There are 31. Eukarya – includes the kingdoms

Protists, Fungi, Plants & Animals

2. Bacteria – corresponds to the kingdom Eubacteria

3. Archaea – corresponds to the kingdom Archaebacteria

Introduction to Phylogenetic Kingdoms -6 now!

Monera (old name =Eubacteria and Archaebacteria)

-Prokaryotes, with or without peptidoglycan in cell walls

Protistia – Eukaryotes, diverse, not fungi, plants, or animals

Fungi – Eukaryotes, multicellular (except yeasts), heterotrophic, chitin in cell walls

Plantae – Eukaryotes, multicellular, non-motile, autotrophic, cell wall containing cellulose

Animalia – Eukaryotes, multicellular, motile, heterotrophic, no cell wall

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ArchaeaArchaea live in live in harsh environmentsharsh environments and may represent the first cells to and may represent the first cells to have evolved.have evolved.

Sewage Sewage treatment treatment

plants, plants, thermal thermal

vents, etc.vents, etc.

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EubacteriaEubacteria, some of which , some of which cause human diseases, are cause human diseases, are

present in almost present in almost all all habitatshabitats on earth. on earth.

Many bacteria are important Many bacteria are important environmentally and environmentally and

commercially.commercially.

Live in the Live in the intestines intestines of animalsof animals

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Domain Eukarya is Domain Eukarya is Divided into 4 KingdomsDivided into 4 Kingdoms

•ProtistaProtista (protozoans, algae…) (protozoans, algae…)

•FungiFungi (mushrooms, yeasts …) (mushrooms, yeasts …)

•PlantaePlantae (multicellular plants) (multicellular plants)

•AnimaliaAnimalia (multicellular (multicellular animals) animals)

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ProtistaProtista

•Most are Most are unicellularunicellular

•Some are Some are multicellularmulticellular

•Some are Some are autotrophicautotrophic, , while others are while others are heterotrophicheterotrophic

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FungiFungi•Multicellular,Multicellular,

except yeastexcept yeast

•Absorptive Absorptive heterotrophsheterotrophs (digest food (digest food outside their outside their body & then body & then absorb it)absorb it)

•Cell walls Cell walls made of made of chitinchitin

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PlantaePlantae

•MulticellularMulticellular

•AutotrophicAutotrophic

•Absorb Absorb sunlight sunlight to make glucose to make glucose – Photosynthesis– Photosynthesis

•Cell walls made Cell walls made of of cellulosecellulose

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AnimaliaAnimalia

•MulticellularMulticellular

•Ingestive Ingestive heterotrophsheterotrophs (consume (consume food & digest food & digest it inside their it inside their bodies)bodies)

•Feed on Feed on plants or plants or animalsanimals

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Dichotomous KeyingDichotomous Keying

•Used to identify Used to identify organismsorganisms

•Characteristics given in Characteristics given in pairspairs

•Read both Read both characteristicscharacteristics and and either go to another set either go to another set of characteristics of characteristics OROR identify the organismidentify the organism

1 A. Has Hair -------------go to 2 B. Does not have hair--go to 42 A. Has one eye----------Bofeng B. Has two eyes --------go to 3 C. Has three eyes ------ Rishabh3 A. Has antennas --------Kayla B. Has no antennas ----Erik 4 A. Has wings ------------Charles B. Has no wings -------- Ishraf

Bofeng

Kayla

Rishabh

Erik

CharlesIshraf

ExampleExample of Dichotomous Example of Dichotomous

KeyKey