1 / 31

Taxonomy

Taxonomy. BIOL 1407. What is taxonomy?. Naming and classification of organisms Traditionally based on system developed by Carolus Linnaeus. Two Components to Linnaean System. Idea of binomial nomenclature – naming organisms Idea of hierarchy – classifying organisms into groups.

iharris
Télécharger la présentation

Taxonomy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Taxonomy BIOL 1407

  2. What is taxonomy? • Naming and classification of organisms • Traditionally based on system developed by Carolus Linnaeus

  3. Two Components to Linnaean System • Idea of binomial nomenclature – naming organisms • Idea of hierarchy – classifying organisms into groups

  4. Binomial Nomenclature • Idea is that each species is assigned a unique name • Name has two parts: a genus name and a specific epithet • Together, the two words make up the scientific name of the species

  5. Binomial Nomenclature • Allows clear communication between different researchers • Prevents confusion that can occur from use of common names

  6. Example • Scientific Name: Yucca filamentosa • Common Names: Bear grass, Adam’s needle, Weak-leaf yucca • Picture Credit: Larry Allain @ USDA-NRCS PLANTS Database

  7. Scientific Names: General Guidelines • Scientific names are based on Latin. • Scientific names are alwaysitalicized (when printed) or underlined (when hand-written) • Modern scientific names follow international guidelines

  8. Scientific Names: General Guidelines • Different species with the same genus name are considered to be more closely related to each other than to other species. • Genus name is always capitalized; specific epithet is always lower-case.

  9. Example • Panthera leo – lion • Panthera onca – jaguar • Panthera pardus – leopard • Uncia uncia – snow leopard • Lions, jaguars and leopards are more closely related to each other than to snow leopards.

  10. Scientific Names: General Guidelines • Some scientific names, especially older ones, include the name of the person who discovered or described the species. • Example: The Tibetan antelope Pantholopshodgsonii was named for the 19th century British naturalist who discovered it, Brian Houghton Hodgson. • Picture Credit: Rhett A. Butler, mongabay.com

  11. General Naming Guidelines • Other scientific names refer to a region, such as Didelphisvirginiana (Virginia opossum) • Picture Credit: Alden M. Johnson @ California Academy of Sciences

  12. General Naming Guidelines • Scientific names often include some feature or trait of the species. The specific epithet for the hairy bush clover, Lespedezahirta, refers to its “hairy” stem. • Picture Credit: Tom Barnes, University of Kentucky

  13. Scientific Names Poison Arrow Frog Dendrobates azureus “Blue Tree-Walker” • Picture Credit: Jessie Cohen, Courtesy of Smithsonian National Zoo @ nationalzoo.si.edu

  14. Scientific Names Giant Anteater Myrmecophaga tridactyla “Eater of ants, with three fingers” Picture Credit: Courtesy of Smithsonian National Zoo @ nationalzoo.si.edu

  15. Taxonomic Hierarchy • Linnaeus classified organisms into groups, based on shared characteristics. • There were different levels of groups. • Each level nests within the group above. • In his system, the Kingdom was the most inclusive. Successive groups contain fewer and fewer organisms.

  16. Linnaean Hierarchy • Kingdom (most general) • Phylum • Class • Order • Family • Genus • Species (unique)

  17. Two Kingdom System • Linnaeus classified organisms into two kingdoms: Plantae and Animalia • Plants, fungi, photosynthetic protists were all included into Plantae • Animals, heterotrophic protists (such as Amoeba) were included into Animalia • This system was revised several times.

  18. Five Kingdom System • Proposed by Whittaker in 1968 • Kingdom Monera – prokaryotes • Kingdom Protista – protists (eukaryotes that were not plants or animals or fungi) • Kingdom Plantae – plants • Kingdom Fungi – fungi • Kingdom Animalia – animals

  19. Five Kingdom Classification Scheme

  20. Research by Carl Woese • Research done by Carl Woese in the 1980s with rRNA comparisons showed that all prokaryotes are not closely related. • Prokaryotes are divided into two groups: true bacteria and archaeans (formerly called archaebacteria)

  21. rRNA Comparisons • Based on rRNA, plants, animals and fungi share more similarities with each other than with bacteria or archaeans • All eukaryotes share more similarities with each other than with prokaryotes • Archaeans share more similarities with eukaryotes than with bacteria

  22. Domains • Based on rRNA studies, Woese proposed a Three Domain System • Domain Bacteria – “true” bacteria (prokaryotes) • Domain Archaea – archaeans (prokaryotes) • Domain Eukarya – eukaryotes

  23. Modern Taxonomic Hierarchy • Domains are the highest level (most inclusive), above Kingdoms. • Kingdom Monera is no longer used. • Kingdom Protista is no longer used. • Kingdoms Plantae, Fungi and Animalia are still in use.

  24. Modern Taxonomy • Modern taxonomy is in a state of flux. • As genomes are sequenced for different organisms, evolutionary relationships often become more clear. Taxonomy should reflect those relationships. • Expect major changes in taxonomy over the next several years.

  25. Three Domains

  26. Three Domains

  27. Modern Taxonomic Hierarchy

  28. ModernTaxonomic Hierarchy

  29. Example: Giant Anteater Myrmecophaga tridactyla Domain: Eukarya Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Xenarthra Family: Myrmecophagidae Genus: Myrmecophaga Species: Myrmecophaga tridactyla

  30. Categories and Taxa • In this hierarch of classification, the different levels are categories. • A named group at a level is called a taxon (plural = taxa). • The giant anteater is in Class Mammalia. Class is the category; Mammalia is the taxon. • The giant anteater is in Family Myrmecophagidae. Family is the category; Myrmecophagidae is the taxon.

  31. The End Unless otherwise specified, all images in this presentation came from: Campbell, et al. 2008. Biology, 8th ed. Pearson Benjamin Cummings.

More Related