Unit 11: Classification Ch. 3 Classification Taxonomy = branch of biology that deals w/ naming & classifying organisms.

Why Things Are Classified? What does it mean to classify? –to group things based on similarities Examples of classifying in everyday life… Why are organisms classified? –easier to find –show shared traits –show relationships among living & extinct species

Why Things Are Classified? How are organisms classified? –very broad characteristics  very specific based on evolutionary relationships –A group of organisms is called a taxon. Tools used to classify organisms… –dichotomous keys

1 st classification system –Aristotle 2 groups –1. plants »by type of stem –2. animals »by environment Early Classification According to Aristotle, which of these 3 animals would be classified more closely?

Carolus Linnaeus “Father of Modern Taxonomy” –2 main groups = k ingdoms plants animals –Also used: genus –similar species species –organisms w/ similar traits Beginning of Modern Classification

Linnaeus 1 st to consistently use binomial nomenclature –2 name system written: Genus species or Genus species –Genus = 1st name, capitalized –species = 2nd name, lower case & descriptive Ex. Common nameGenus & species –Humans Homo sapiens –White Oak tree Quercus alba –Red Oak tree Quercus rubra –Bottlenose dolphinTursiops truncatus Beginning of Modern Classification

Why don’t we use common names? 1.two organisms can have same common name, but not sci. name 2.scientific names rarely change 3.scientific names are written in same language around the world Beginning of Modern Classification

current system reflects relationships –based on evolutionary ancestry –can change in response to new data According to the phylogenetic tree on the right who are humans most closely related to? How Scientists Classify Today

slightly different classification systems –5 Kingdom system Monera, Protista, Fungi, Plantae, Animalia –6 Kingdom system Monera split into Archaea (Archaebacteria) & (Eu)bacteria… other 4 kindgoms remain same –3 Domain system Archaea, (Eu)bacteria, Eukaryota (Eukarya) –4 kingdoms (Protista, Fungi, Plantae, Animalia) grouped in Eukaryota How Scientists Classify Today

Where would Domain belong in this diagram?

How Scientists Classify Today When using the 5 or 6 Kingdom system –Kingdom largest, most inclusive –species smallest, least inclusive

How Scientists Classify Today When using the 3 Domain system –domain largest, most inclusive –species smallest, least inclusive Domain Eukaryota Domain

What is a species? –Group of organisms capable of mating with one another in nature to produce fertile offspring How Scientists Classify Today

Did  Domain King  Kingdom Phillip  Phylum Come  Class Over  Order For  Family Good  Genus Spaghetti?  species How Scientists Classify Today A trick to help you remember all the major classification groups… King Phillip This is really GOOD!!! I’m so glad I came!

What is the relationship among the levels? –more closely related  share more levels –from Domain down, each level has a new set of criteria that must be shared DOMAIN Eukaryota How Scientists Classify Today

Once an organism shares a more specific taxon (lower group) it MUST share the more unifying taxa (higher groups) How many levels of classification do we share with dolphins?

Domain: Archaea Kingdom: Monera prokaryotic unicelluar feeding –heterotrophic or autotrophic other characteristics –older, less complex bacteria –live in extreme environments examples –bacteria: in salt lakes at hydrothermal vents

Staphylococcus cyanobacteria Domain: Eubacteria Kingdom: Monera prokaryotic unicelluar feeding –heterotrophic or autotrophic other characteristics –modern, more complex bacteria evolved from Archaea –most common & very diverse –free-living or pathogenic examples –Staphylococcus –E. coli –cyanobacteria

Domain: Eukaryota All are eukaryotic 4 of the 5 kingdoms –1. Protista –2. Fungi –3. Plantae –4. Animalia

Domain: Eukaryota 1. Kingdom: Protista eukaryotic mostly unicelluar feeding –heterotrophic or autotrophic other characteristics –can be plant-like, animal- like, or fungus-like examples –Amoeba –Paramecium –Euglena –algae Amoeba Paramecium Euglena

eukaryotic multicelluar*** feeding –heterotrophic digest food outside & absorb nutrients other characteristics –cell walls made of chitin –decomposers & parasites examples –mushrooms –molds –yeast (*** unicellular) Domain: Eukaryota 2. Kingdom: Fungi

eukaryotic multicelluar feeding –autotrophic photosynthesis other characteristics –cell walls made of cellulose –produce oxygen examples –mosses –ferns –grasses –shrubs –trees Domain: Eukaryota 3. Kingdom: Plantae

eukaryotic multicelluar feeding –heterotrophic other characteristics –no cell wall Domain: Eukaryota 4. Kingdom: Animalia examples –invertebrates insects worms sponges corals –vertebrates fish birds amphibians reptiles mammals

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