CLASSIFICATION Why Classification? * Study the diversity of life * Group and name organisms in a logical manner Taxonomy: science of classifying living and creating scientific names Early Classification Aristotle: 350 B.C. * Greek philosopher who classified organisms into two kingdoms: Plants or Animals Plants: size and structures Animals: behavior and habitat * What might be some problems with his system? Video Clip http://www.glencoe.com/sec/science/biology/ bio2000/biomovies/e20_1int.html Linneaus: Mid 1700s: developed a new classification system His system grouped organisms based on morphology (physical appearance) Created 7 taxonomic levels Carolus Linnaeus (1707-1778) Linnaeus’ Taxonomic levels 7 taxonomic levels (taxon=category) : Kingdom, Phylum, Class, Order, Family, Genus, Species Phrase to remember order of levels: King Phil Came Over For Good Soup 7 Taxonomic levels Can be compared to our address system Kingdom (broadest)----- Country Phylum -------------------- State Class----------------------- County Order -------------------- City Family -------------------- Zip Code Genus -------------------- Street Species (most specific)- House # Leopard Human Taxonomy Kingdom Animalia -many cells (multicellular) -cells have a nucleus - don't have any chlorophyll Phylum Chordata -had NOTOCHORD. That's a rod made out of cartilage. Class Mammalia -warm blooded -nurse young -hair Order Primata -eyes on the front of the head Family Hominidae -walk upright -no tail -s shaped spine Genus Homo Species sapien ORGANISM GROUP NAME HUMAN CHIMPANZEE HOUSE CAT LION HOUSEFLY KINGDOM Animalia Animalia Animalia Animalia Animalia PHYLUM Chordate Chordate Chordate Chordate Arthropoda CLASS Mammal Mammal Mammal Mammal Insect ORDER Primates Primates Carnivora Carnivora Diptera FAMILY Hominidae Hominidae Felidae Felidae Muscidae GENUS Homo Pan Felis Felis Musca SPECIES sapiens troglodytes domestica leo domestica Scientific Name Homo sapiens Pan troglodytes Felis domestica Felis leo Musca domestica What is a Species? Group of similar organisms that reproduce NATURALLY, with consistent pregnancies, and create FERTILE offspring Binomial Nomenclature Scientific Names Scientists avoid using common names to prevent confusion because they vary from region to region. Blue Jay Eastern Blue Jay Cyanocitta cristata Blue Jay Western Blue Jay Cyanocitta stellari Binomial Nomenclature Scientific Names 2 part naming system that consists of genus and species. Rules for writing scientific names: Genus: first word - first letter capitalized Species: second word - lowercase Both are underlined or italicized EX: Homo sapiens : Human beings Sialia sialis: Eastern Bluebird North American Pocket Mice Pergonathus californicus Found in California Pergonathus nelsoni Discovered by someone named Nelson Pergonathus spinatus Has prickly fur Common Factors-Same genus, different species, so would produce infertile offspring. Review What are the eight characteristics of life? Living things are made of cells Must reproduce Same genetic code Must grow and develop Must obtain energy Must respond to environment Must maintain homeostasis Must adapt and evolve Review What are the 7 taxonomic levels in order from most general to most specific? Kingdom Phlyum Class Order Family Genus Species Review Who created the classification system that is currently in use? Linnaeus Review The two name scientific naming system for organisms is called ____________. Binomial nomenclature Review Which taxon comes first in a scientific name? Genus Review How should you format the scientific name? Genus- capitalized Species-lower case Either underline or italicize Modern Classification Problems with traditional system: focused only on morphology (appearance) Modern Criteria for Classification uses: *Morphology/Anatomy *Development *DNA Comparison- DNA sequences *Evolutionary descent Dichotomous Key Tool for classifying unknown organisms Uses 2 sets of descriptors, known as couplets Steps: Always start at #1 Follow couplets based on organism’s characteristics 1) Peacock Flounder 2) Spotted Goat Fish 3) Glassy Sweeper 4) Squirrel Fish 5) Spotted Eagle Ray 6) Band Tail Puffer 7) Spotted Moray Eel 8) Glass Eyed Snapper 9) Trumpet Fish Rajidae skates Alopiidae Thresher Shark Pristophoridea Saw Shark Carcharhinidae Tiger Sharks Scyliorhinidae Cat Shark Rhincodontidae Whale Shark Isuridae Mackerel Sharks Squalidae Dogfish Sharks Dasyatidae Stingrays Scapanorhynchidae Goblin shark Pseudotriakidae False Cat sharks Hexanchidae cow sharks Sphyrnidae Hammerhead shark Mobulidae Manta Ray Evolutionary Classification Cladistics: the science of grouping organisms based on evolutionary descent, not just morphology. Cladogram: a diagram that shows evolutionary relationships among organisms. Derived character: characteristic that appears in recent parts of a lineage, but not in the older members. Used to build cladograms. Cladogram www.biologycorner.com/cladogram/cladogram_2.htm# Cladogram Practice Examine the sample cladogram, each letter on the diagram points to a derived character, or something different (or newer) than what was seen in previous groups. Match the letter to its character. Note: this cladogram was created for simplicity and understanding, it does not represent the established phylogeny for insects and their relatives. To make a cladogram, you must first look at the animals you are studying and establish the characteristics that they share and ones that are unique o each group. For the animals on the table, indicate whether the characteristic is present or not.