Part One • What is classification? • Phylogeny • Binomial Nomenclature • Dichotomous Keys
What is classification? • Whenever you place similar items together, you are classifying them. • Look at the images on the next page. • What do they have in common? • How many different ways can you divide these flying things into groups? • Choose a method to classify these objects. Start with 2 headings and then subdivide each group.
Phylogeny • The evolutionary relationships between organisms. • Used today to classify organisms into 6 Kingdoms: • Plants –complex multicellular cells, make own food • Animals – complex multicellular cells, heterotrophs (eat other organisms) • Fungi – complex multicellular cells, decomposer, ex. Mushrooms, mold, & mildew • Protists – complex unicellular, ex. algae • Archaebacteria – one celled, live in extreme environments • Eubacteria – one celled, most bacteria (Secondary Science Program: Rhode Island College)
Kingdoms Phylum Class Order Family Genus Species Pneumonic Device: King Phillip can only find green socks!
Kingdom is the largest category and then it gets subdivided into smaller and smaller groups. • Species is the smallest group - only organisms that are the same species can mate & produce fertile offspring
Questions • Which two organisms on the previous slide are most closely related? • Which are more closely related, the horse and cockroach or horse and elephant?
Binomial Nomenclature • Two word naming system. The first word is the genus. A genus is a group of similar species. The second word is the species. • Example: Maple trees are in the genus Acer. There are many kinds of maple trees, so they have a species name also. • Acer rubrum – Red Maple • Acer saccharum – Sugar Maple
Why do we use Binomial Nomenclature? • Helps avoid mistakes. • Example: Lizards Desert Iguana (Disposaurus doralis) (Seaman) Green Iguana (Iguana Iguana) (Myska)
Organisms with similar evolutionary histories are classified together. • Question: Look at the names of these organisms. Which are more closely related? • Panthera onca jaguar • Lynx rufus bobcat • Panthera tigris tiger • Puma concolor cougar
Gives descriptive information about the species. • Example: Acer rubrum – Red Maple. Rubrum is Latin for red. • Allow information about organisms to be easily organized into books, pamphlets, etc.
Question • List, in order, the 7 categories used to classify a single organism?
Dichotomous Keys • Detailed list of identifying characteristics and scientific names • Example: page 26 in textbook
Phyla of the Animal Kingdom • Annelida • Arthropoda • Chordata • Cnidaria • Echinodermata • Mollusca • Nematoda • Porifera
Phylum Annelida • Bilateral symmetry • Uniformly segmented body • Parapodia – fleshy “legs” • Bristles • Examples: earthworms, bristle worms, leeches
Phylum Annelida Bristle Worm (Read)
Phylum Arthropoda Bilateral symmetry Segmented body Hard exoskeleton Jointed legs Examples: insects, spiders, crustaceans
Phylum Arthropoda (Sparks, 2007) (NOAA, 2005) (FreeDigitalPhotos.net, no date)
Phylum Chordata • Bilateral symmetry • Have or had a tail • Notochord • Embryonic gill slits • Examples: vertebrates, sea squirts
Phylum Chordata (Elasmodiver.com, no date) (Fireflower Systems Limited, no date) (Hicker, 2008)
Phylum Cnidaria • Radial symmetry • Ring of tentacles around mouth • Stinging cells • Examples: jellyfish, sea anemones, coral (Muller, 2001)
Phylum Cnidaria (Chpt. 10) (BBC)
Phylum Echinodermata • Five part radial symmetry • Tube feet • Spiny skin • Examples: sea stars, sea cucumbers, sea urchins, sand dollars
Phylum Echinodermata (Zubi, 2005) (Zubi, 2003) (Ditchburn, no date)
Phylum Mollusca • Bilateral symmetry • Have or had a shell • Soft bodied with a muscular “foot” • Examples: snails, slugs, bivalves, squid, octopus
Phylum Mollusca (Huston, no date) (Xylem Elements, 2008) (Zander, 2007)
Phylum Nematoda • Bilateral symmetry • Round, unsegmented body • Cuticle • Example: round worms, hook worms, pin worms
Phylum Nematoda (Myers, 2001)
Phylum Porifera • Asymmetrical or radial symmetry • Have many pores • Made up of a group of cells that have aggregated but do not form tissues • Example: Sponges
(Missouri Botanical Garden, 2002) Phylum Porifera
Follow-up Questions • Sketch an organism with bilateral symmetry and one with radial symmetry. Draw the lines of symmetry over your sketch. • Which of the following is an animal? • Mushroom • Spider • Maple tree • Bacteria