Classification of OrganismsClassification of Organisms

It’s always changing!!!!It’s always changing!!!!

TaxonomyTaxonomy

The science of The science of describing, naming, and describing, naming, and classifying organismsclassifying organisms

How Did We Get Our Modern How Did We Get Our Modern System of Classification?System of Classification?

Binomial NomenclatureBinomial Nomenclature A system for giving each organism a A system for giving each organism a

two-word scientific name that consists two-word scientific name that consists of the genus name followed by the of the genus name followed by the species namespecies name

Carl Linnaeus, a Swedish biologist in Carl Linnaeus, a Swedish biologist in the 1700sthe 1700s

Approach has been universally Approach has been universally adoptedadopted

The organism’s “scientific name”The organism’s “scientific name”

Genus & SpeciesGenus & Species A level of classification that comes after family and A level of classification that comes after family and

that contains similar speciesthat contains similar species

The first word in the scientific nameThe first word in the scientific name– CapitalizedCapitalized

The second word (the species name)The second word (the species name)– LowercasedLowercased

Homo sapiensHomo sapiens

FamilyFamily Similar generaSimilar genera

Hominidae (Great Apes)Hominidae (Great Apes)

OrderOrder A grouping of similar familiesA grouping of similar families

PrimatesPrimates

ClassClass A grouping of orders A grouping of orders

with common propertieswith common properties

MammaliaMammalia

PhylumPhylum Classes with similar Classes with similar

characteristicscharacteristics

Chordata (subphylum: Chordata (subphylum: Vertebrata)Vertebrata)

KingdomKingdom Similar phyla grouped togetherSimilar phyla grouped together

AnimaliaAnimalia

DomainDomain Largest and most inclusive taxonomic categoryLargest and most inclusive taxonomic category

Similar kingdoms grouped togetherSimilar kingdoms grouped together

3 domains3 domains

– Archaea (prokaryotes)Archaea (prokaryotes)

– Bacteria (prokaryotes)Bacteria (prokaryotes)

– Eukarya (4 kingdoms of eukaryotes)Eukarya (4 kingdoms of eukaryotes)

DomainDomain

DomainDomain

DomainDomain Archaea (prokaryotes)Archaea (prokaryotes)

– Kingdom ArchaebacteriaKingdom Archaebacteria– Live in extreme environments: volcanic hot springs, brine pools, Live in extreme environments: volcanic hot springs, brine pools,

black organic mudblack organic mud– Cell wall lacks peptidoglycan Cell wall lacks peptidoglycan (murein): made of sugars and (murein): made of sugars and

amino acidsamino acids

Bacteria (prokaryotes)Bacteria (prokaryotes)– Kingdom EubacteriaKingdom Eubacteria– Free-living soil organisms to deadly parasitesFree-living soil organisms to deadly parasites– Cell wall contains peptidoglycanCell wall contains peptidoglycan

DomainDomain EukaryaEukarya

– Kingdom ProtistaKingdom Protista

– Kingdom FungiKingdom Fungi

– Kingdom PlantaeKingdom Plantae

– Kingdom AnimaliaKingdom Animalia

How Do I Remember It All?How Do I Remember It All? DDo o KKindly indly PPay ay CCash ash OOr r FFurnish urnish GGood ood SSecurityecurity DDearear K King ing PPhilip hilip CCame ame OOver ver FFor or GGood ood SSoup oup DDidid K Kermit ermit PPuke uke CCookies ookies OOn n FFozzie's ozzie's GGreen reen SSweater?weater?

– DomainDomain– KingdomKingdom– PhylumPhylum– ClassClass– OrderOrder– FamilyFamily– GenusGenus– SpeciesSpecies

Biological SpeciesBiological Species

A group of organisms that can reproduce only A group of organisms that can reproduce only among themselves and that are usually among themselves and that are usually contained in a geographic regioncontained in a geographic region

Convergent EvolutionConvergent Evolution

The process by which The process by which unrelated species become unrelated species become more similar as they more similar as they adapt to the same kind of adapt to the same kind of environmentenvironment

Analogous CharactersAnalogous Characters

Similarities that arise through convergent Similarities that arise through convergent evolutionevolution

PhylogenyPhylogeny The evolutionary The evolutionary

history of a species or history of a species or taxonomic grouptaxonomic group

Discovered through Discovered through molecular sequencing molecular sequencing data and morphological data and morphological data matricesdata matrices

CladisticsCladistics

A phylogenetic classification system that uses A phylogenetic classification system that uses shared derived characters and ancestry as the shared derived characters and ancestry as the sole criterion for grouping taxasole criterion for grouping taxa

Example: birds and mammals: Example: birds and mammals: – a backbone is an a backbone is an ancestral characterancestral character– feathers are a feathers are a derived characterderived character

CladogramCladogram A diagram that is based on patterns of shared, derived A diagram that is based on patterns of shared, derived

traits and that shows the evolutionary relationships traits and that shows the evolutionary relationships between groups of organismsbetween groups of organisms