History and Use of Biological Classification

CLASSIFICATION & TAXONOMY grouping based on similarities Taxonomy: Branch of Biology The science of classifying/grouping and naming of organisms

Aristotle’s Classification Scheme Greek philosopher who developed first classification system Divided all organisms into 2 GROUPS: Non motile (plants) Motile (animals) Plants grouped by: size (small, medium, large) Animals grouped by: where they lived (air, water, land)

Binomial Nomenclature A system for naming organisms by structure created by Carl Linnaeus: Although Linneaus didn’t realize it, but by classifying organisms by structure, he was also classifying them by evolutionary relationship Written in Latin Includes the organisms : Genus: CAPITALIZED (noun) means beginning Species: lowercase (adj.) Example: Homo (man) sapien (wise/thinking)

Scientific & Common Names Scientific Name: genus and species name Iguana iguana Felis domesticus Common name: Organism is commonly called Not used in the scientific community Green Iguana Domestic Cat

Linnaeus’ System of Classification 1. Linnaeus’ hierarchical system of classification includes seven levels. They are, from largest to smallest: kingdom, phylum, class, order, family, genus, and species. Kingdom Phylum Class Order 2. In taxonomic nomenclature, each level is called a taxon (plural: taxa) or taxonomic category. Family Genus Species

Dumb King Phillip Came Over For Gooseberry Soup!

Linnaeus’ System of Classification 3. The kingdom is the largest and most inclusive (includes) of the taxonomic categories. 4. Species is the smallest and least inclusive of the taxonomic categories. 5. The more taxonomic categories that two organisms share, the more closely related they are considered to be. What do the scientific names of each bear tell you about their similarity to each other? Ailuropoda melanoleuca Ursus arctos Ursus maritimus

Application of Linnaeus’ Classification System Organism Cat Wolf Fly Kingdom Animalia Phylum Chordata Arthropoda Class Mammalia Insecta Order Carnivora Diptera Family Felidae Canidae Muscidae Genus Felis Canis Musca Species domesticus lupus domestica

Application of Linnaeus’ Classification Systmem 1. What type of animal is M. domestica? 2. Which two animals listed on the table are most closely related? 3. At what classification level does the evolutionary relationship between cats and wolves diverge (become different)? Family Level

The “New” Evolutionary Classification Categories that represent lines of evolutionary descent Not just physical similarities This new method is called: Evolutionary Classification Scientists classify organisms based on their Evolutionary Beginnings

Evolutionary Classification 1. Darwin’s theories on descent with modification have led to the study of phylogeny, which is the study of evolutionary relationships among organisms. 2. Biologists group organisms into categories that represent lines of evolutionary descent or phylogeny and not just physical similarities. 3. Grouping organisms based on their evolutionary history is called evolutionary classification.

Cladograms A diagram that shows evolutionary relationships Cladograms show derived characteristics Help scientists understand how one lineage branched from another in the course of evolution

Traditional Classification vs. Cladogram Evolutionary Decent: Class Physical Similarities Conical Shells Appendages Crustaceans Gastropoda Crab Barnacle Limpet Molten exoskeleton Segmentation Free-swimming larvae TRADITIONAL CLASSIFICATION CLADOGRAM

Evolutionary Classification and Cladograms 1. Cladistic analysis identifies and considers new characteristics that arise as lineages evolve over time. 2. Derived characteristics are those that appear in recent parts of a lineage but not in its older members. 3. When a derived characteristics appears ahead of an organism listed on a cladogram, the organism lacks that derived characteristics. 4. When a derived characteristics appears below, beneath, or before the organism, the organism possesses or has that derived characteristics.

CLADOGRAM Mouse Chimp Lizard Pigeon Fish Frog Hagfish Feathers Fur & Mammary Glands Claws or Nails Lungs Jaws

Kingdoms Broadest of all taxa Grouped into 3 domains: Bacteria : Eubacteria 2. Archea: Archeabacteria 3. Eukarya: Protista, Fungi, Plantae, and Animalia

Characteristics of the 6 Kingdoms 1. Kingdom Eubacteria: a. all microscopic prokaryotes b. almost all are unicellular c. non-motile d. commonly called bacteria 2. Kingdom Archaebacteria: a. prokaryotes b. live in extreme environment

3. Kingdom Protista: a. eukaryotes b. uni and multicellular c. live in moist environments d. most are simple, microscopic & mobile *Examples: paramecium, amoeba, euglena & algae

b. Uni and Multicellular c. Consumers that do not move 4. Kingdom Fungi: a. Eukaryotes b. Uni and Multicellular c. Consumers that do not move d. Decompose dead organisms &/or waste products *Examples: mushrooms, molds, & mildew

5. Kingdom Plantae: a. stationary, multicelluar eukaryotes b. Photosynthetic c. Autotrophs *(make own food) *Examples: plants

6. Kingdom Animalia: a. Multicellular b. Consumers that eat & digest other organisms (heterotrophs) c. May be herbivores, carnivores & omnivores *Examples: Animals

Complete Classification of Humans Kingdom: (Animalia) Phylum: (Chordata) Dorsal nerve cord-cartilage Vertebrae Subphylum: (Vertebrata) Class: (Mammalia) 5. Order: (Primates) 6. Family: (Hominid) 7. Genus: (Homo) 8. Species: (sapien)