Finding Order in Diversity

 Scientist have named about 1.5 million species  However, it is estimated that there still are million additional species yet to be discovered

 In order to best study life’s diversity, classifying organisms helps to group them in a logical manner It allows all scientists to have a shared name for each individual species It gives information about each organism  i.e. Why do we call birds, birds?  The scientific term for giving organisms an universally accepted name is called TAXONOMY

 Taxonomist name organisms both in broad and specific terms  Give organisms scientific names helps to classify what the organism looks and acts like  It helps to both give information and avoid confusion

 Why do we call some people doctors, lawyers, teachers, garbage men, mechanics?  Take it a step further Pediatricians Dermatologist Oncologists Cardiologists Etc

 Taxonomy helps to avoid confusion caused by regional names  Felis Concolor

 When scientists first tried to name each organism, names of over 20 words were common  However, Binomial Nomenclature, which is a 2-name naming structure was proposed by Carolus Linnaeus

 Each species gets a 2-part scientific name The whole name is always italicized The first name is always capitalized, second is lower cased For example, the Grizzly Bear has the name of Ursus arctos The first name is the Genus, and the second is the Species

 Linnaeus came up with a 7 taxon level naming system.  They are (in order from largest to smallest) Kingdom Phylum Class Order Family Genus Species

 Species Refers individually to each unique species  Genus Is a group of closely related species

 Family Species that share many characteristics (like all types of bears would fit in one family  Order: Is a broad taxonomic grouping for similar families  Class Contains organisms that share similar orders For example, carnivoria is placed in the class mammalia

 Phylum  Is composed of several different classes. Includes many different organisms, yet they do share similar important traits Includes  Aves (mammals and birds)  Reptilia  Amphibia  Chordata (all fish)

 Kingdom  Is the largest and most inclusive category. Includes  Eubacteria  Archaebacteris  Protista  Fungi  Plantae  Animalia

 Modern advances in molecular technology has led to a broader category than kingdom, it called Domain  There are 3 different domains 1. Eukarya 2. Bacteria 3. Archaea

 Members are unicellular and prokaryotic  Have thick rigid cell walls that surround the cell membrane that have peptidoglycan  Corresponds to the kingdom Eubacteria Diversity includes free living soil to deadly parasites Some photosynthesize, some don’t Some need oxygen, to others it’s toxic

 All are unicellular and prokaryotic  Live in the most extreme of environments Volcanic hot springs, brine pools, black organic mud that has no oxygen  Cell walls don’t have peptidoglycan, and contain unusual lipids  This domain corresponds to the kingdom Archaebacteria

 All organisms in eukarya have a nucleus  Is composed of 4 kingdoms: protista, fungi, plantae, and animalia

 Is composed of eukaryotic organisms that cannot be classified as animals, plants or fungi  It is the LEAST satisfying category that we have, due to complex variety  Some are multicellular, most are unicellular  Some are photosynthetic  Some are heterotrophic  Some share some characteristics with plants, some with animals, and some with fungi

 All members in this kingdom are heterotrophs  Have Cell walls that contain chitin  Most feed on dead or decaying organic matter They ingest digestive enzymes into their food source and then absorb the smaller broken down molecules into their bodies  Some examples are mushrooms and yeast

 All members of this kingdom are multicellular photosynthetic autotrophs  All are non-motile  Their cell wall contain cellulose  Includes Cone bearing plants Flowering plants Mosses Ferns

 All are multicellular and heterotrophic  Cells do not have cell walls  Most are mobile  Extremely vast in variety