Biological Classification
Why classify? Humans have developed classification systems in order to make sense of the abundant biological diversity that exists in nature.
What is Classification? Classification is the arrangement of organisms into orderly groups based on their similarities Classification is also known as taxonomy Taxonomists are scientists that identify & name organisms copyright cmassengale
The Biological Classification System The system is hierarchical. Larger groups are more general and smaller groups are more specific. For example, the phylum Chordata includes both lions and lionfish, but the genus Panthera includes only lions. Chordata Panthera
The Biological Classification System The system is phylogenetic. It is meant to reflect the evolutionary interrelatedness among groups. For example, the grey wolf and the dog both are placed in the genus Canis because of their close evolutionary relationship.
Classification Groups Taxon ( taxa-plural) is a category into which related organisms are placed There is a hierarchy of groups (taxa) from broadest to most specific Domain, Kingdom, Phylum, Class, Order, Family, Genus, species copyright cmassengale
Hierarchy-Taxonomic Groups Domain Kingdom Phylum (Division – used for plants) Class Order Family Genus Species BROADEST TAXON Genus and species are the two names used to identify specific organisms in the binomial system of classification. Division is used for plants. Most Specific copyright cmassengale
copyright cmassengale Dumb King Phillip Came Over For Gooseberry Soup! copyright cmassengale
copyright cmassengale Domains Broadest, most inclusive taxon Three domains Archaea and Bacteria are unicellular prokaryotes (no nucleus or membrane-bound organelles) Eukarya are more complex and have a nucleus and membrane-bound organelles copyright cmassengale
copyright cmassengale ARCHAEA Kingdom - ARCHAEBACTERIA Probably the 1st cells to evolve Live in HARSH environments Found in: Sewage Treatment Plants (Methanogens) Thermal or Volcanic Vents (Thermophiles) Hot Springs or Geysers that are acid Very salty water (Dead Sea; Great Salt Lake) - Halophiles copyright cmassengale
copyright cmassengale ARCHAEAN copyright cmassengale
copyright cmassengale BACTERIA Kingdom - EUBACTERIA Some may cause DISEASE Found in ALL HABITATS except harsh ones Important decomposers for environment Commercially important in making cottage cheese, yogurt, buttermilk, etc. copyright cmassengale
Live in the intestines of animals copyright cmassengale
Domain Eukarya is Divided into Kingdoms Protista (protozoans, algae…) Fungi (mushrooms, yeasts …) Plantae (multicellular plants) Animalia (multicellular animals) copyright cmassengale
copyright cmassengale Protista Most are unicellular Some are multicellular Some are autotrophic, while others are heterotrophic Aquatic copyright cmassengale
copyright cmassengale Fungi Multicellular, except yeast Absorptive heterotrophs (digest food outside their body & then absorb it) Cell walls made of chitin copyright cmassengale
copyright cmassengale Plantae Multicellular Autotrophic Absorb sunlight to make glucose – Photosynthesis Cell walls made of cellulose Growth, with increases in size and number of cells, is part of development. Development involves many stages from conception until death. copyright cmassengale
copyright cmassengale Animalia Multicellular Ingestive heterotrophs (consume food & digest it inside their bodies) Feed on plants or animals copyright cmassengale
copyright cmassengale
Kingdom The most general of the seven levels. Most biologists currently recognize six different kingdoms: Archaebacteria, Eubacteria, Protists, Fungi, Plants, Animals
Phylum (plural: phyla) Each kingdom is subdivided into smaller, more specific groups called phyla. Examples of different phyla Mollusk (snails, slugs, clams, oysters) Cnidarian (jelly-fish) Annelida (Earthworms, Leeches) Arthropoda (butterfly, other insects) Chordata (vertebrates)
Class Each phylum is subdivided into smaller groups called classes. Class Agnatha (eel shaped) Class Amphibia Class Aves Class Mammalia Class Osteichthyes (Fish) Class Reptilia
Order Each class is subdivided into smaller groups called orders. Rodentia Order: Called "rodents." Beaver. Carnivora Order: Called "carnivores." Large predators, most of which eat a variety of plant material as well. Includes: Raccoons, Foxes, Bears, Coyotes, Weasels, Skunks, Dogs, and Cats. Artiodactyla Order: Called "even-toed hoofed animals." Large, vegetarian animals. Includes Deer.
Family Each order is subdivided into smaller groups called families.
Genus (plural: genera) Each family is subdivided into smaller groups called genera.
Species Each genus is subdivided into smaller groups called species. The species is the most specific level of classification.
copyright cmassengale Carolus Linnaeus Called the “Father of Taxonomy” Developed the modern system of naming known as binomial nomenclature Two-word name (Genus & species) copyright cmassengale
copyright cmassengale Standardized Naming Binomial nomenclature used Genus species Latin or Greek Italicized in print Capitalize genus, but NOT species Underline when writing Turdus migratorius copyright cmassengale American Robin
Binomial Nomenclature copyright cmassengale Which TWO are more closely related?
Seven Levels of Taxonomic Classification for the… Kingdom-Animalia Phylum-Chordata Class-Mammalia Order-Carnivora Family-Felidae Genus-Panthera Species-leo Seven Levels of Taxonomic Classification for the… Lion
Seven Levels of Taxonomic Classification for the… Kingdom-Plantae Phylum-Tracheophyta Class-Anthophyta Order-Asterales Family-Compositae Genus-Taraxacum Species-officinale Seven Levels of Taxonomic Classification for the… Dandelion
Giant panda Red fox Ginkgo tree Tiger Polar bear Gray squirrel Pick one animal, write down all levels of classification for that animal. Make sure you write down the scientific name at the end correctly. Giant panda Red fox Ginkgo tree Tiger Polar bear Gray squirrel Red Maple tree White oak Grizzly bear Black bear
copyright cmassengale Dichotomous Keying Used to identify organisms Characteristics given in pairs Read both characteristics and either go to another set of characteristics OR identify the organism copyright cmassengale
Example of Dichotomous Key 1a Tentacles present – Go to 2 1b Tentacles absent – Go to 3 2a Eight Tentacles – Octopus 2b More than 8 tentacles – 3 3a Tentacles hang down – go to 4 3b Tentacles upright–Sea Anemone 4a Balloon-shaped body–Jellyfish 4b Body NOT balloon-shaped - 5 copyright cmassengale