Classifying Living Things

Classifying – grouping things according to similarities Taxonomy – science of classifying and naming organisms - The term is derived from the Greek taxis (“arrangement”) and nomos (“law”).

Aristotle Greek philosopher Classified organisms into two kingdoms. Plant Animal Animal Kingdom – divided into 3 groups Air Land Water

Problem with Aristotle’s system Frogs part of life in water Part of life on land Needed more logical and finer tuned classification system

Carolus Linnaeus Swedish physician and naturalist Created system to classify organisms based on similarities in body structures and systems Also; size, color, shape and methods of obtaining food

6 Kingdoms of classification of organisms Kingdom Monera – has been divided into; Archaebacteria Eubacteria

Organisms are placed in each kingdom based on characteristics Presence of nucleus Single-celled Many-celled Ability to make food Ability to move

Finer classification King Phillip Came Over For Good Spaghetti

species Smallest category of classification Organisms within a species can reproduce and produce fertile offspring

Naming of organisms All organisms need an exact name

Binomial Nomenclature- 2 names

Binomial nomenclature Organism’s scientific name Latin name Genus name: group of different organism that have similar characteristics always capitalized Species name: more precise classification organisms belonging to same species can mate always lower case No two organisms have the same name

Canis familiaris Domesticated dog

Canis lupus Grey wolf

Canis latrans Coyote Latrans – barking dog

Dichotomous key – tool used to identify organisms Dichotomous means "divided in two parts". At each step of the process of using the key, the user is given two choices;