 What methods are used to classify living things into groups?  Why does every species have a scientific name?

 Aristotle grouped everything into two simple groups – animals or plants.  Animals were classified based on the presence of “red blood”, their environment, and the shape and size.  Plants were classified based on the structure and size and whether it was a tree, shrub, or herb.

 In the 1700s, Carolus Linneaus, a Sweedish physician and botanist, classified organisms into two main groups called Kingdoms.  In 1969, an American biologist proposed a five kingdom system for classifying organisms: Monera, Protista, Fungi, Plantae, and Animalia.

 Current classification system is called systematics. It uses all the evidence known about organisms to classify them, including cell type, habitat, the way it obtains food and energy, structure and function, and common ancestry.  Recently, Kingdom Monera was split into two groups – Bacteria and Archaea. This led to another level of classification called domains.  Copy table from board

 When Linnaeus grouped organisms into kingdoms, he also developed a system for naming organisms, which we still use today.  Binomial Nomenclature – gives each organism a two-word scientific name.  The genus, a group of similar species, is always written first and capitalized.  The species, a group of organisms that are similar enough to reproduce, is always written second and in lower case.

 Scientific names are always italicized or underlined.  Helarctos malayanus – tropical sun bear  Ursus maritimas – polar bear  Canis lupus – Gray wolf  Canis familiaris – domestic dog

 DomainDutch  KingdomKings  PhylumPlay  ClassCards  OrderOROn  FamilyFat  GenusGreen  SpeciesStools

 Dichotomous Key – series of descriptions arranged in pairs that leads the user to the ID of an unknown organism.

 Cladogram – branched diagram that shows the relationships among organisms, including common ancestors.