Classification is the grouping of organisms according to their characteristics. Early systems were developed by Aristotle and John Ray. Linnaeus developed the binomial nomenclature system using genus and species names. Organisms are classified into a hierarchy of taxonomic ranks including kingdom, phylum, class, order, family, genus and species. Dichotomous keys use yes/no questions to identify organisms based on observable traits. The document provides examples of classification systems and guides the reader through creating a simple dichotomous key.

1. The Diversity of LifeClassification of Living Things

2. What is classification?Classification is the grouping of things according to characteristicsThe science of classifying organisms is known as taxonomy

3. Early classification systemsAristotle grouped animals according to the way they moved John Ray was the first to use the term “species”

4. Binomial NomenclatureDeveloped by LinnaeusTwo-name systemEach organism has a first name (genus); and a second name (species)scientific names are usually italicized with only the genus name CAPTITALIZEDTwo different organisms cannot have the same scientific name

5. Some ExamplesPantheraleoPantherapardusPantheratigrisPseudolithoxustigrisArchaiustigrisCypraeatigris

6. Levels of Taxonomy

7. Kings Play Cards On Fat Green Stools

8. Identifying and Classifying an organismGeneral characteristics allow identification of kingdom, phylum, class and perhaps order but to get more specific, special tools are used called dichotomous keysA dichotomous key uses a series of yes/no questions to help you identify the species you are observing

9. An example (part of a dichotomous key)Questions

10. Practice – determine the identity of each of these fish using the key in your notes

11. Practice – determine the identity of each of these fish using the key in your notesSpotted goat fishGlassy sweeperPeacock flounderBand tail pufferSquirrel fishSpotted eagle rayTrumpet fishGlass eye snapperMoray eel

12. Activity – create your own dichotomous key to identify different kinds of pasta