Science, Tech, Math › Science Linnaean Classification System (Scientific Names) How Linnaeus Taxonomy Works Share Flipboard Email Print SHEILA TERRY/SCIENCE PHOTO LIBRARY / Getty Images Science Chemistry Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated July 30, 2019 In 1735, Carl Linnaeus published his Systema Naturae, which contained his taxonomy for organizing the natural world. Linneaus proposed three kingdoms, which were divided into classes. From classes, the groups were further divided into orders, families, genera (singular: genus), and species. An additional rank beneath species distinguished between highly similar organisms. While his system of classifying minerals has been discarded, a modified version of the Linnaean classification system is still used to identify and categorize animals and plants. Why Is the Linnaean System Important? The Linnaean system is important because it led to the use of binomial nomenclature to identify each species. Once the system was adopted, scientists could communicate without the use of misleading common names. A human being became a member of Homo sapiens, no matter what language a person spoke. How to Write a Genus Species Name A Linnaean name or scientific name has two parts (i.e., is binomial). First is the genus name, which is capitalized, followed by the species name, which is written in lowercase letters. In print, a genus and species name is italicized. For example, the scientific name for the house cat is Felis catus. After the first use of a full name, the genus name is abbreviated using only the first letter of the genus (e.g., F. catus). Be aware, there are actually two Linnaean names for many organisms. There is the original name given by Linnaeaus and the accepted scientific name (often different). Alternatives to Linnaean Taxonomy While the genus and species names of Linneaus' rank-based classification system are used, cladististic systematics is increasingly popular. Cladistics categorizes organisms based on traits that can be traced to the most recent common ancestor. Essentially, it's classification based on similar genetics. Original Linnaean Classification System When identifying an object, Linnaeus first looked at whether it was animal, vegetable, or mineral. These three categories were the original domains. Domains were divided into kingdoms, which were broken into phyla (singular: phylum) for animals and divisions for plants and fungi. Phyla or divisions were broken into classes, which in turn were divided into orders, families, genera (singular: genus), and species. Species in v were divided into subspecies. In botany, species were divided into varietas (singular: variety) and forma (singular: form). According to the 1758 version (10th edition) of the Imperium Naturae, the classification system was: Animals Classis 1: Mammalia (mammals)Classis 2: Aves (birds)Classis 3: Amphibia (amphibians)Classis 4: Pisces (fish)Classis 5: Insecta (insects)Classis 6: Vermes (worms) Plants Classis 1. Monandria: flowers with 1 stamenClassis 2. Diandria: flowers with 2 stamensClassis 3. Triandria: flowers with 3 stamensClassis 4. Tetrandria: flowers with 4 stamensClassis 5. Pentandria: flowers with 5 stamensClassis 6. Hexandria: flowers with 6 stamensClassis 7. Heptandria: flowers with 7 stamensClassis 8. Octandria: flowers with 8 stamensClassis 9. Enneandria: flowers with 9 stamensClassis 10. Decandria: flowers with 10 stamensClassis 11. Dodecandria: flowers with 12 stamensClassis 12. Icosandria: flowers with 20 (or more) stamensClassis 13. Polyandria: flowers with many stamensClassis 14. Didynamia: flowers with 4 stamens, 2 long and 2 shortClassis 15. Tetradynamia: flowers with 6 stamens, 4 long and 2 shortClassis 16. Monadelphia; flowers with the anthers separate, but the filaments united at the baseClassis 17. Diadelphia; flowers with the stamens united in two groupsClassis 18. Polyadelphia; flowers with the stamens united in several groupsClassis 19. Syngenesia; flowers with 5 stamens having anthers united at the edgesClassis 20. Gynandria; flowers having stamens united to the pistilsClassis 21. Monoecia: monoecious plantsClassis 22. Dioecia: dioecious plantsClassis 23. Polygamia: polygamodioecious plantsClassis 24. Cryptogamia: organisms that resemble plants but don't have flowers, which included fungi, algae, ferns, and bryophytes Minerals Classis 1. Petræ (rocks)Classis 2. Mineræ (minerals)Classis 3. Fossilia (fossils)Classis 4. Vitamentra (possibly meant minerals with nutritional value or some vital essence) The mineral taxonomy is no longer in use. The ranking for plants has changed, since Linnaeus based his classes on the number of stamens and pistils of a plant. The animal classification is similar to the one in use today. For example, the modern scientific classification of the house cat is kingdom Animalia, phylum Chordata, class Mammalia, order Carnivora, family Felidae, subfamily Felinae, genus Felis, species catus. Fun Fact About the Taxonomy Many people assume Linnaeus invented ranking taxonomy. In actuality, the Linnaean system is simply his version of ordering. The system actually dates back to Plato and Aristotle. Reference Linnaeus, C. (1753). Species Plantarum. Stockholm: Laurentii Salvii. Retrieved 18 April 2015.