Chapter 18Classification

What is Classification?Classification is the grouping of

objects based on similarities◦Classifying Biology and Chemistry as

Science is a type of classification◦We classify organisms to help name

them and to create orderTaxonomy is the branch of biology that

groups and names organisms

How did taxonomy begin?What do you call this animal?

◦Mountain lion, cougar, puma, panther

What is Classification?Binomial nomenclature gives each

species a two-part scientific name◦The first word is the genus, the

second is the species◦Grizzly bear: Ursus arctos◦Polar bear: Ursus maritimus◦Giant panda: Alluropoda

melanoleuca◦Most are Latin◦Developed by Carolus Linnaeus in

late 1700s

What is Classification?Linnaeus’s classification included a

hierarchal system with 7 levelsTaxon: grouping (categories) of organisms,

plural is taxa◦Kingdom: taxon of similar phyla◦Phylum: taxon of similar classes◦Class: taxon of similar orders◦Order: taxon of similar families◦Family: taxon of similar genera; example

cat family is Felidae◦Genus: taxon of similar species◦Species: specifies organism; Homo

sapiens

Taxonomy

Taxonomy

ClassificationHow do we determine how to group

organisms together?◦What similarities/differences are

most important?◦How do you classify a dolphin? Is it

more similar to a fish or a cat?Darwin’s ideas of evolution led to the

study of phylogeny (evolutionary relationships among organisms)

ClassificantionGrouping organisms based on their

evolutionary history is called evolutionary classification◦Species with the same genus are

more closely related than another genus

◦Same genus all share a common ancestor

◦The farther you go up in taxa, the further back the common ancestor was

Cladograms show relationships of evolutionary classification

Cladogramshttps://

www.youtube.com/watch?v=ouZ9zEkxGWg

Cladograms

Dichotomous KeyA dichotomous key is multiple sets of

paired statements used to identify organisms

http://nationalzoo.si.edu/Education/ConservationCentral/walk/walk4.html

3 DomainsBacteria, Archaea, and EukaryaBacteria and Archaea are prokaryotes.

◦Domain Bacteria has Kingdom Eubacteria. “normal” bacteria

◦Domain Archaea has Kingdom Archebacteria. “weird” bacteria

EukaryaKingdom Protista

◦Most are unicellular◦Live in moist environments◦Diverse in ways they obtain

nutrition. Ex. amoeba http://www.cellsalive.com/parasit.htm

Kingdom Fungi◦Heterotrophic decomposers◦Cell walls of chitin, ex. mushroom;

pictures

EukaryaKingdom Plantae

◦Autotrophic, multicellular, have tissues◦Cell walls of cellulose◦Vascular plants – have vessels that

transport water and sugars (ferns, conifers, flowering plants) Xylem – tissue that moves water Phloem – tissue that moves sugars

◦Nonvascular plants do not have these vessels., ex. mosses

Kingdom Animalia – multicellular heterotrophs. Do NOT have cell walls

Classification of Living Things

Domain, Kingdom, Phylum…Did DomainKing KingdomPhilip PhylumCross ClassOver OrderFor FamilyGood GenusSoup Species