Taxonomy The science of classifying organisms. Classify To arrange according to similarities or differences.
Why classify? Biologists use classification to organize living things into groups so that the organisms are easier to study. We classify to make our lives easier.
History of Taxonomy
Aristotle Simple classifications Used common names Plant or animal? If an animal does it have blood? does it – Fly – Swim – Walk/Crawl
DISCUSSION QUESTION - Using Aristotle's 3- group system (based on movement), name 2 animals that would fit each of the 3 groups.
Problems with this system? Some animals can walk, swim, and fly
What technology helped scientist improve the classification system? Microscope -1600s
Carolus Linnaeus 1700s Described organisms with two word names, instead of polynomials Developed binomial nomenclature First word = Genus name (Capitalized) Second word = species name (lowercase) scientific name – Example Canis lupus Always italicized or underlined
Why binomial nomenclature? Binomial - 2 name Nomenclature – naming system Much easier than a 10+ word name under old “polynomial system” Same name no matter where you go (Latin) Less confusion
Devil Cat
Ghost Cat
Mountain Lion
Screaming Cat
Puma
Florida Panther
Cougar
Felis concolor
Taxonomic Hierarchy Names organisms and their relationships from very broad to very specific
Classification of Living Things
Milky way Solar System Earth U.S. Ohio Westerville Mainsail Dr. 283
Domain Kingdom Phylum Class Order Family Genus Species
Three Domains of Life There used to be 2, why do you think there are 3 now?
Domain Archaeabacteria: Life's Extremists...! Archaea are found in the harshest environments on Earth, and are the oldest known organisms on Earth, appearing in the fossil record over 3.6 BILLION years ago (3,600,000,000 years ago!)
Domain Bacteria (or Eubacteria): is familiar to most people when associated with human or animal disease. However, most bacterial species do not (and cannot) cause disease. Most species even play beneficial roles for humans by producing antibiotics and food.
Domain Eukarya A single-celled or multicellular organism whose cells contain a distinct membrane-bound nucleus. (Organism’s cell has a nucleus.)
Domain Kingdom Phylum Class Order Family Genus Species
Pro = before
Why has taxonomy changed throughout history? Do you think it will continue to change?
Prokaryotes We are now filling out our charts
Archaea Unicellular prokaryotes Autotrophs Cell wall
Eukaryotes Eu = true Have membrane bound nuclei
Most are unicellular
Phylum examples Chordata Cord Chordates Hollow dorsal nervous chord, notochord, pharyngeal slits, endostyle, post-anal tail about 100,000+ Cnidaria Stinging nettle Coelenterates Nematocysts (stinging cells) about 11,000 Ctenophora Comb bearer Comb jellies Eight "comb rows" of fused cilia about 100 modern species Cycliophora Wheel carrying Symbion Circular mouth surrounded by small cilia
52 Classification of Humans Kingdom Animalia PhylumChordata ClassMammalia OrderPrimates FamilyHominidae GenusHomo Speciessapiens
Is your table filled out? Don’t lose it!!!