Taxonomy & Binomial Nomenclature
Why do we classify? To organize organisms into groups that have biological meaning Taxonomy-the study of classifying organisms & assigning each organism a universally accepted name (A.K.A. – Scientific name)
Why don’t scientists use common names? Common names can be confusing to scientists because the same organism may have different common names. Ex) Puma, cougar, panther, mountain lion are all the same animal (Puma concolor) Different species may share a single common name. Ex) Buzzard: US-Vulture; UK- Hawk
How are organism’s scientific names determined? Binomial Nomenclature Created by Carolus Linnaeus Two-part naming system Always written in italics Latin language 1st word is capitalized and 2nd word is lowercased 1st word- genus 2nd word- species (refers to an important trait of an organism or where it lives) Example: Grizzly Bear- Ursus arctos
Linnaeus System of Classification 7 Taxonomic Categories Kingdom Phylum Class Order Family Genus Species King Philip came over for good spaghetti! Do Activity
Modern Evolutionary Classification Problems with “traditional” classification: Classifying organisms with similar body structure or important traits doesn’t necessarily mean they are more closely related. Modern “evolution” classification Strategy of grouping organism together based on evolutionary history (similarities in DNA). Cladogram: a diagram that shows the evolutionary relationship among a group of organisms.
Cladogram is similar to a family tree in that it shows relationships common among relative organisms.
Classification Tools DNA & RNA Molecular Clock Scientist examine DNA & RNA to help determine classification of organism Example: Amer. vulture, African vulture, & Stork Molecular Clock Used to mark evolutionary change in organism by comparing the DNA
Domains & Kingdoms 6 Kingdom System of Classification Three Domains: developed from RNA studies & molecular clocking of organisms 1. Bacteria Includes Kingdom Eubacteria 2. Archaea Includes Kingdom Archaebacteria 3. Eukarya Includes Kingdoms Protista, Fungi, Plantae, & Animalia 6 Kingdom System of Classification Eubacteria Archaebacteria Protista Fungi Plantae Animalia
Classification of Living Things Domain Bacteria Archaea Eukarya Kingdom Eubacteria Archaebacteria Protista Fungi Plantae Animalia Cell Type Prokaryote Eukaryote Cell Structure Cell wall w/ peptidoglycan Cell wall w/o peptidoglycan Cell wall of cellulose in some; some have chloroplast Cell wall of chitin Cell wall of cellulose; chloroplast No cell wall or chloroplast # of Cells Unicellular Most unicellular; some multicellular Most multicellular; some Unicellular Multicellular Mode of Nutrition Autotroph or Hetertroph Hetertroph Autotroph Examples Streptococcus Halophiles Slime molds, giant kelp Mushroom, yeast Mosses, ferns, plants Sponges, insects, fishes, mammals