Week 2

• Aristotle


  An early taxonomist who was a Greek philosopher and organized five hundred types of animals according to habitat and body form
• Aristotle considered animals that gave birth to live young and had lungs as the pinnacle of living perfection
• John Ray (1627–1705)


  An English naturalist who classified more than twenty thousand types of plants and animals
• John Ray's method


  Highly descriptive, distinguished animals by their hoofs, nails, claws, teeth, and toes
• Lichen


  A compound organism that consists of an alga and a fungus
• Carolus Linnaeus (1707–1778)


  The best-known taxonomist who was heavily influenced by John Ray, compared, contrasted, and meticulously listed types of organisms from his earliest childhood; Swedish botanist

  
  

  "Father of Taxonomy"
• Taxonomy


  The science of classifying organisms
• Classification


  An important step in understanding the present diversity and past evolutionary history of life on Earth
• Taxa


  The Linnaean system of classification consists of a hierarchy of groupings, ranging from the kingdom to the species
• Levels of taxa


  • Kingdom
  • Phylum (plural, phyla)
  • Class
  • Order
  • Family
  • Genus
  • Species
• Kingdom


  The largest and most inclusive grouping that consists of organisms that share just a few basic similarities (e.g. plant and animal kingdom)
• Species


  The smallest and most exclusive grouping that consists of organisms that are similar enough to produce fertile offspring together
• Genus


  Closely related species are grouped together in a genus
• Nomenclature


  The practice of assigning scientific names
• Binomial


  Comes from the words "bi" and "nomen"
• Binomial


  "bi" means "two"
• Binomial


  "nomen" meaning "name"
• Species name


  Consists of two parts: the genus or generic name and the specific epithet
• Species name


  • The first letter is always capitalized (e.g. Canis)
  • The specific epithet is not capitalized (e.g. familiaris)
  • Can be in bold letters or underlined or italicized
  • If handwritten, it is underlined
• Dichotomous key


  A tool that helps identify unknown organisms to some taxonomic level (species, genus, family, etc.)
• Dichotomous key

  A series of choices is made that leads to user to the correct identify of a sample organism
• Dichotomous means:

  Divided into two parts
• Dichotomous key


  • Offers for each step, each of which describes key characteristics of a particular organism or group of organisms