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Taxonomy. The Science of Classifying Organisms. The Need for a System. For many years, scientists and other naturalists used common names to describe organisms
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Taxonomy The Science of Classifying Organisms
The Need for a System • For many years, scientists and other naturalists used commonnames to describe organisms • confusing because there were either multiple organisms with the same common name (e.g. “rose”), or a single organism with many common names (e.g. Chinook, Spring, King, Tyee salmon). • *Check out these slides …..
Photo Credits Sea Lion: Bill Lim Ant Lion: AmphioxusLion: law_keven Sea Lion? Antlion? Lion?
Which one of these is NOT actually a bear? Photo Credits Panda: Chi King Koala: Belgianchocolate Black Bear: SparkyLeigh
Consider this……….. • Are all “Grey Wolves” gray? • Are all “Black Bears” black? Grey wolves can be white, black and any shade of gray. Black bears can also be brown or gray
Linnaeus to the Rescue • After trying other systems, scientists settled on a system developed by the Swedish botanist CarolusLinnaeus. • This system was called Binomial Nomenclature which means “two-name naming”.
Binomial Nomenclature • Each organism gets its own two-part scientific name – usually derived from Latin. • E.g. “cougar” = Puma concolor • The first word is called the genus and the second word is called the species. • The first letter of the genus is always capitalized. • The first letter of the species is always lower case • The name is either italicized or underlined.
The Genus • Genus refers to a group of closely related species • Puma jagouaroundi • Puma concolor
Pantheraonca Pantheratigris Pantheraleo Puma concolor
Binomial Nomenclature Structure • Binomial nomenclature gives information about the natural relationships of organisms • It shows exactly where an organism sits in the vast complexity of life • Today, use genetic analysis for classifying organisms
Naming and Organizing are part of the same process • Linnaeus also created a system where we place all organisms into a few *large* groups - KINGDOMS - and then those groups are further divided into smaller groups
Grouping Each group gets smaller and more specific – just think of the way you file things on your computer into folders and subfolders • Kingdom • Phylum • Class • Order • Family • Genus • Species
Kingdom Phylum Class Order Family Genus Species Animalia Chordata Mammalia Carnivora Felidae Panthera tigris Seven Levels of Classification Narrower Broader
To help you remember the list Kids Play Catch Over Farmer Grey`s Stable Kingdom, Phylum, Class, Order, Family, Genus, Species
The Kingdoms • There are currently 5 kingdoms – all organisms can be placed into one of those 5 • Classification into a kingdom is based on certain criteria • Cell type • Number of cells • Nutrition
Kingdom Monera • Prokaryotic (do not have a nucleus) • Unicellular • Autotrophic (produces own energy) or Heterotrophic (obtains energy from food consumed) Eubacteria = common bacteria (E. coli, Salmonella) Archaebacteria = “ancient bacteria”, exist in extreme environments
Kingdom Protista • Eukaryotic (have a nucleus) • Most are unicellular • Can be autotrophic or heterotrophic • Most live in water • Include animal-like (heterotrophs) and plant-like (autotrophs • Examples: Ameba, paramecium, euglena, algae Photo of Ameba by PROYECTO AGUA **/** WATER PROJECT • Catch-all group for eukaryotes which don’t fit into other categories
Kingdom Fungae • Eukaryotic (have a nucleus) • Multicellular(most) • Heterotrophic (mainly decomposers) • Cell walls have chitin • Lack motility Photos by nutmeg66
Kingdom Animalia Photo by Tambako the Jaguar • Eukaryotic (have a nucleus) • Multicellular • Heterotrophic (must consume food) • Motile (some only in certain stages of life) • Lack cell walls • Ex: birds, insects, worms, mammals, reptiles, humans Photo by Eduardo Amorim
Kingdom Plantae • Eukaryotic (cells have nucleus) • Multicellular • Autotrophic (can make own food; photosynthesis) • Cell walls have cellulose Photo by hira3