taxonomy, phylogeny and organization

• Taxonomy


  The study of the kinds and diversity of organisms and of the evolutionary relationships among them
• Systematics


  The study of the kinds and diversity of organisms and of the evolutionary relationships among them
• Naming system

  • Must reflect the order and relationships that arise from evolutionary processes
• Taxonomic work

  1. Description of new species

  2. Organization of animals into groups (taxa) based on degree of evolutionary relatedness

  3. Creation of a phylogeny for a group of animals
• Phylogeny


  A description of the evolutionary history of a group of organisms, usually depicted using tree diagrams
• Taxonomic hierarchy

  Domain<|>Kingdom<|>Phylum<|>Class<|>Order<|>Family<|>Genus<|>Species
• As one moves down through the hierarchy from domain toward species, one is looking at groups derived from more recent ancestors and a smaller subset of more closely related animals
• Taxonomists have the option of subdividing these ranks (e.g., subphylum, superclass, and infraclass) to express relationships between any two ranks
• Taxon (pl., taxa)


  Any grouping of animals that shares a particular set of characteristics
• Taxon

  • Housefly (Musca domestica)
• The binomial system is still used today
• Von Linné (Carolus Linnaeus) (1707–1778) recognized that different species could be grouped into broader categories based on shared characteristics