Classification of Organisms Essential Question: Why do scientists classify living things?

History of Classification Aristotle was a Greek philosopher who lived more than 2000 years ago. He was the first to document that living things could be classified. Many of his original ideas are still used in today’s classification system. Linnaeus's lived from 1707-1778. He created the hierarchy of classification we use today. The science of classifying organisms is called TAXONOMY. Specifically, he is responsible for the 2-name or binomial given to each organism on Earth. The first name comes from the genus, while the second name is the species.

DOMAINS The largest…MOST GENERAL classification groups are the 3 DOMAINS. This is a new addition to the classification hierarchy established in the 1990s. Domains group organisms by their cellular structure and function. (We are going to learn more about this in the upcoming science units.) As cell research continues, technology reveals more and more about Earth’s organisms, so Taxonomy is an ever-changing system.

The Old System: 5 Kingdoms

New System: 6 Kingdoms Archebacteria Eubacteria Once the domains were established, scientists recognized the cell structure and function of the Monera kingdom should be separated.

Classification Hierarchy Classification begins very general with the domain… then becomes increasingly more specific as it reaches the species.

Mnemonic Devices Mnemonic devices help us remember information. Here are a few to help you remember the Hierarchy of Classification… Kingdom Phylum Class Order Family Genus Species Examples of Mnemonic Devices: King Phillip Came Over For Grandma’s Spaghetti. Keeping Precious Creatures Organized For Grumpy Scientists. Can you come up with a funny phrase to help us remember?

Binomial Nomenclature: The naming of organisms Remember Linnaeus, we mentioned him at the start of the lesson. He’s the scientist who developed the way we name all organisms. All organisms have a 2-part name, or a binomial. The binomial is written in latin and created using the genus, followed by the species. This Bear is named: Ursus americanus American Black Bear

These two organisms are similar, which means genetically they have a lot in common. Their differences is what places them in different species. Canis domesticus Canis lupus