Taxonomy and Classification Dr. D. Mitchell Biology

Taxonomy Taxonomy – the branch of biology concerned with the classifications of organisms. Organisms are classified in a hierarchy of larger and more inclusive categories.

Carolus Linneaus developed binomial nomenclature the scientific naming system Classified organisms based on physical and structural similarities. is a two-word naming system. two words are the genus and species descriptor This scientific name uses Latin words

Allows scientists to talk about particular species without confusion. Scientific Names Allows scientists to talk about particular species without confusion. Allows scientists around the world to communicate clearly about living things.

Homo = genus, sapiens =species Scientific Names Criteria: Always written underlined or in italics First letter of the genus is always capitalized. The species descriptor is never written without the full or abbreviated genus name preceding it. Unique to each organism. Example: Homo sapiens Homo = genus, sapiens =species

Basic taxon in the Linnaean system is the species. a group of organisms defined by the classification scheme. Example: class, species Basic taxon in the Linnaean system is the species.

Levels of Classification KingdomMost Inclusive Phylum Class Order Family Genus SpeciesLeast Inclusive King Phillip Came Over For Great Spaghetti Kings Play Cards On Fat Green Stools

Each level is included in the level above it. Levels get increasingly specific from kingdom to species.

limitations of The Linnaean classification system Created before technology the study of organisms at the molecular level. Focuses only on perceived physical similarities or differences. Does not account for genetic similarities due to evolutionary change.

Classification schemes 1753 Two Kingdoms Plantae and Animalia 1866 Ernst Haeckel proposed Three Kingdoms Plantae, Animalia, and Protista 1938 Herbert Copeland proposed Four Kingdoms Plantae, Animalia, Protista, and Fungi

1959 1977 Robert Whittaker proposed Five Kingdoms Plantae, Animalia, Protista, Fungi, and Monera 1977 Carl Woese proposed Six Kingdoms Split Monera into two Kingdoms Plantae, Animalia, Protista, Fungi, Eubacteria, and Archaebacteria.