classification

• Classification


  A way to group and organise the millions of different species on Earth
• Ancestors often classified species based on what they looked like
• Simple names don't tell us much about how related different species are
• Linnaean system


  A classification system proposed by Carl Linnaeus in the 1700s that groups species together according to their characteristics and bone structures
• Levels of the Linnaean system

  • Kingdom
  • Phylum
  • Class
  • Order
  • Family
  • Genus
  • Species
• Binomial naming system


  A system where species are named by their genus and species names, written in italics with only the first letter of the genus capitalised
• As microscopes improved and more was learned about internal structures, new classification models were proposed and combined with the Linnaean system
• Three domain system


  A classification system proposed by Carl Woese in the 1990s that introduced three new categories called domains, placed above kingdoms: Eukaryota, Bacteria, and Archaea
• Bacteria are sometimes referred to as "true bacteria" and Archaea as "primitive bacteria"
• Evolutionary trees


  Diagrams that show the evolutionary relationships between different species or groups by linking common ancestors
• Scientists compared the structure and DNA of different species, including fossil records, to learn about evolutionary relationships
• Mnemonic


  A phrase used to help remember a list of terms in a particular order