Classification of Living Things 7th Diversity of Living things (Mod B) U1L5

History of Classifying: daily life Aristotle (over 2000 years ago) * classified organisms as animal or plant Where lived? Size? * too many exceptions 2. Carolus Linnaeus ( late 18th century) * grouped organisms with similar structures. * used 2-word system to name species (binomial nomenclature)

* Not only external & internal features but also - genetic makeup Modern systems based on phylogeny – the evolutionary history of an organism. (How organism has changed over time.) * Not only external & internal features but also - genetic makeup -fossil ancestry -embryo development Phylogenetic tree

Today we use 6 kingdoms. Animalia Plantae Fungi Protista Bacteria Archaea BrainPop – 6 kingdoms

There are three domains used in classification today Domain Eukarya Includes Kingdom Animalia, Kingdom Plantae, Kingdom Fungi and Kingdom Protista Domain Bacteria Includes Kingdom Bacteria Domain Archaea Includes Kingdom Archaea

* Species is smallest category. (subspecies) * Domain is first & largest category. * Species is smallest category. (subspecies) Domain --------------------- Eukarya

Organisms in the same species can mate & produce fertile offspring Organisms in the same species can mate & produce fertile offspring. (Today we use DNA to determine species.) More classification groups organisms share, the more closely related they are.

Steller’s sea lio n Walrus Northern fur seal Kingdom Animalia Animalia Animalia Phylum Chordata Chordata Chordata Class Mammalia Mammalia Mammalia Order Pinnipedia Pinnipedia Pinnipedia Family Otariidae Odobenidae Otariidae Genus Eumetopias Odobenus Callorhinus Species jubatus rosmarus urinus

Common names can be misleading. ex. Jellyfish Is it a fish??? Can have same common name for different species. ex. robin Turdus migratorius Eopsaltria australis Erithacus rubecula

Binomial Nomenclature (scientific names) Binomial Nomenclature (scientific names) ** Might tell you what organism looks like, where it is found, or who discovered it. Genus name – capitalized both italicized Species name – lowercase or underlined Acer rubrum or Acer rubrum Acer saccharum or Acer saccharum ( 10 Ridiculous scientific names - https://www.youtube.com/watch?v=E4N5tQDo76c

Why use scientific names? To avoid mistakes. To show that organisms in the same genus are related. To give descriptive information. ex. Turdus migratorius To allow information to be organized.

Tools for Identifying Organisms: Field guides – pictures & descriptions of organisms. Cladograms Dichotomous Keys * Detailed lists of identifying characteristics that include scientific names.

Cladograms (“branching diagrams”) Shows relationships between species Organisms grouped by common characteristics (in this cladogram) Characteristics listed along line Branches of organisms extend from line Organisms on branches above line have that characteristic Comparing DNA Sequences - https://www.youtube.com/watch?v=OSKwuOccAak Describes how DNA is used to see relationships between organisms Only show through 4:10 (it gets too technical after that) Careful @1:45 – implication that humans are “nothing special” - discuss

                                                                                                                                 Right side is deer mouse