2. 18-1 History of Taxonomy Taxonomy  Branch of biology that names and groups organisms according to their characteristics and evolutionary history.  Aristotle was first to devise a scheme. *Plants were based on differences in stems *Animals were based on where they lived

3. Taxonomy However, this was not good enough because common names change from one locale to another. So another scheme was invented which is still used today. This was made by Carolus Linnaeus. Carolus Linnaeus  Swedish  Used organism’s morphology (form and structure). Devised 7 different levels of organization.

5. Levels of Organization Kingdom (largest category) Phylum (uses Division for plants) Class Order Family Genus species (smallest category) single type.

6. Binomial Nomenclature  System scientists use to identify organisms.  Gives species name (scientific name).  2 part name *genus *species (species identifier) Always Latin so that all scientists in the world are able to identify organisms by the same name.

7. Binomial Nomenclature  Ex. Humans Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primates Family: Hominidae Genus: Homo (italics and capital) Species: sapiens (italics and lower case) "King Philip came over for good spaghetti."

8. Binomial Nomenclature Modern taxonomists consider the evolutionary history (phylogeny) of the organism. Smaller subsets: Genus Species Subspecies (animals of same species) Genus Species Variety (plants of same species)