Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Unit 11: Classification Ch. 3 Classification Taxonomy = branch of biology that deals w/ naming & classifying organisms. Why Things Are Classified? • What does it mean to classify? –to group based on similarities • Examples of classifying in everyday life…? • Why are organisms/objects classified? –easier to “find” –show shared traits –show relationships among living & extinct species Why Things Are Classified? • What is a dichotomous key? – a tool used for classification • At each step, the user is given two choices. – Each alternative leads to another question… » until the item is identified. • What are two ways to make a dichotomous key? – branching “tree” diagram – list format Why Things Are Classified? • How are organisms classified? – very broad characteristics very specific • Based on…? – evolutionary relationships – What is a group of organisms called? • taxon (plural = taxa) – How many taxa are there? » 8 (Domain species) Domain Early Classification • Who devised the 1st classification system? –Aristotle • How did he classify organisms? –1. plants » by type of stem –2. animals » by environment According to Aristotle, which of these 3 animals would be classified more closely? Beginning of Modern Classification • Who was the “Father of Modern Taxonomy”? –Carolus Linnaeus • How did he classify organisms? –2 main groups = kingdoms » plants » animals –Also used: » genus ~similar species » species ~organisms w/ similar traits Beginning of Modern Classification • How did Linnaeus name organisms? – used binomial nomenclature • 2 name system – written: Genus species or Genus species » » – Genus = 1st name, capitalized species = 2nd name, lower case & descriptive Ex. Common name » » » » Humans White Oak tree Red Oak tree Bottlenose dolphin Genus & species Homo sapiens Quercus alba Quercus rubra Tursiops truncatus Beginning of Modern Classification • Why don’t we use common names? 1. two organisms can have same common name, but not sci. name 2. scientific names rarely change 3. scientific names are written in same language around the world How Scientists Classify Today • Our current classification system reflects…? – relationships • based on evolutionary ancestry • According to the phylogenetic tree on the right, who are humans most closely related to? How Scientists Classify Today • Can classification systems change? – Yes. • Why? – With scientific advancements, we gain new data & learn more about organisms… How Scientists Classify Today • Classification systems we’re going to discuss: – 5 Kingdom system • Monera, Protista, Fungi, Plantae, Animalia – 6 Kingdom system • Monera split into Archaea (Archaebacteria) & (Eu)bacteria… other 4 kingdoms remain same – 3 Domain system • Archaea, (Eu)bacteria, Eukaryota (Eukarya) – 4 kingdoms (Protista, Fungi, Plantae, Animalia) grouped in Eukaryota Where would Domain belong in this diagram? How Scientists Classify Today • When using the 5 or 6 Kingdom system… – Which group is largest & most inclusive? • Kingdom – Which is smallest & least inclusive? • species How Scientists Classify Today • When using the 3 Domain system… Domain – Which group is largest & most inclusive? – domain – Which group is smallest & least inclusive? – species Domain Eukaryota How Scientists Classify Today • What is a species? – group of organisms capable of mating with one another in nature to produce fertile offspring How Scientists Classify Today • A trick to help you remember all the major classification groups… • • • • • • • • Did King Phillip Come Over For Good Spaghetti? Domain Kingdom Phylum Class Order Family Genus species This is really GOOD!!! I’m so glad I came! King Phillip How Scientists Classify Today • What is the relationship among the levels? – from Domain down, each level has a new set of criteria that must be shared – Organisms that are more closely related share… • more levels DOMAIN Eukaryota Once an organism shares a more specific taxon (lower group) it MUST share the more unifying taxa (higher groups) How many levels of classification do we share with dolphins? Domain: Archaea (archaebacteria) • prokaryotic • unicellular • feeding Kingdom: Monera – heterotrophic or autotrophic • other characteristics – older, less complex bacteria – live in extreme environments • examples – bacteria: • in salt lakes • at hydrothermal vents Domain: Bacteria (eubacteria) • prokaryotic • unicellular • feeding Kingdom: Monera – heterotrophic or autotrophic • other characteristics Staphylococcus – modern, more complex bacteria • evolved from Archaea – most common & very diverse – free-living or pathogenic • examples – Staphylococcus – E. coli – cyanobacteria cyanobacteria Domain: Eukaryota • All are eukaryotic • 4 of the 5 (or 6) kingdoms – 1. Protista – 2. Fungi – 3. Plantae – 4. Animalia Domain: Eukaryota 1. Kingdom: Protista Amoeba • eukaryotic • mostly unicellular • feeding – heterotrophic or autotrophic • other characteristics – can be plant-like, animallike, or fungus-like Paramecium • examples – – – – Amoeba Paramecium Euglena algae algae Euglena Domain: Eukaryota 2. Kingdom: Fungi • eukaryotic • multicellular*** • feeding – heterotrophic • digest food outside & absorb nutrients • other characteristics – cell walls made of chitin – decomposers & parasites • examples – mushrooms – molds – yeast (*** unicellular) • eukaryotic • multicellular • feeding Domain: Eukaryota 3. Kingdom: Plantae – autotrophic • photosynthesis • other characteristics – cell walls made of cellulose – produce oxygen • examples – – – – – mosses ferns grasses shrubs trees Domain: Eukaryota 4. Kingdom: Animalia • eukaryotic • multicellular • feeding – heterotrophic • other characteristics – no cell wall • examples – invertebrates • • • • insects worms sponges corals – vertebrates • • • • • fish birds amphibians reptiles mammals Links • • • • http://www.brainpop.com/science/diversityoflife/classification/preview.weml http://anthro.palomar.edu/animal/default.htm http://www.ruf.rice.edu/~bioslabs/studies/invertebrates/kingdoms.html http://www.nclark.net/Classification