Classification & Taxonomy

Classification vs. Taxonomy Taxonomy – branch of biology that names and groups organisms according to similar characteristics Classification – scheme or mechanism by which organisms are organized

ARISTOTLE: first person to group or classify organisms into two groups Plants vs. Animals

Aristotle’s System PLANTS: ANIMALS: Based on size of stem Based on where they lived

Problems? Not all organisms fit into Aristotle’s two groups (plants or animals) Ex: Bacteria & Fungi

Problems? Ex: A jelly fish isn’t a fish, but a seahorse is! Common names can be misleading Ex: A jelly fish isn’t a fish, but a seahorse is! Sea cucumber sounds like a plant but… it’s an animal!

Problems? Common names vary from place to place Ex: puma, catamount, mountain lion, cougar are all names for same animal

Problems Same organisms have different names in different countries. Chipmunk Streifenhornchen (German) Tamia (Italian) Ardilla listada (Spanish)

Middle Ages - Solution Some early scientists devised scientific names using long descriptions in LATIN. Ex. RED OAK tree Quercus foliis obtuse-sinuatis setaceo-mucronatis “oak with leaves with deep blunt lobes bearing hairlike bristles”

PROBLEM w/ Latin Naming? Names too long, hard to remember! Names don’t show relationships between different animals

Carolus Linnaeus to the rescue! Carolus Linneaus: devised a classification system based on _________________ (Organism’s form & structure) MORPHOLOGY (1707-1778)

Linnaeus’s System Involved two components: binomial nomenclature heirarchy

Binomial Nomenclature: Bi means two Nomen means name

BINOMIAL NOMENCLATURE (2 name naming system) 1st name = _______________ Always capitalized GENUS NAME SPECIES IDENTIFIER 2nd name = _________________ Always lower case Both names are ______________ or written in ____________. UNDERLINED ITALICS

Binomial nomenclature Humans Homo sapiens Homo sapiens

Binomial Nomenclature Vampire bat Desmodus rotundus Eastern chipmunk Tamias striatus

Kingdom Phylum Class Order Family Genus Species King Phillip Came Over SEVEN LEVELS OF TAXONOMIC ORGANIZATION Kingdom Phylum Class Order Family Genus Species King Phillip Came Over For Good Spaghetti

Kingdom Phylum Class Order Family Genus Species Animalia Chordata HEIRARCHY Kingdom Phylum Class Order Family Genus Species Animalia Chordata Mammalia Carnivora Felidae Panthera leo

So what do we use now? MODERN TAXONOMY Still uses Linnaeus’s system: but we have added more _____________ KINGDOMS Remember: Aristotle only had 2.

Modern Taxonomy

Kingdom Pro/Eu Uni/Multi Cell Auto/ Hetero Ex Archaebac-teria Prokaryotic Unicellular Both Extremo-phile Eubacteria Pro Uni E. Coli Protista Eukaryotic Euglena, Amoeba Fungi Eu Hetero Yeast, mushroom Plant Multi Auto Trees, Ferns Animal Bird, shark