Classifying Living Things

Classification Classification is the process of grouping things based on their shared traits. Biologists use classification to organize living things into groups, so that the organisms are easier to study The scientific study of how living things are classified is called taxonomy.

Classification System Carolus Linnaeus is the Swedish scientist who developed a classification system based on the organisms’ observable features. Linnaeus’s naming system is called binomial nomenclature because each organism is given a two part name.

Binomial Nomenclature The first part of the organism’s name is its genus. This is a classification grouping that contains similar, closely related organisms. The second part of the organism’s name is its species. A species is a group of similar organisms that can mate and produce fertile offspring.

Seven Levels of Classification Today’s classification system uses several levels to classify organisms. The more characteristics that organisms have in common, the more level they share. Kingdom Phylum Class Order Family Genus Species

Dichotomous Keys Taxonomist have developed special guides know as dichotomous keys to aid in identifying unknown organisms. A dichotomous key consists of several pairs of descriptive statements that have only two responses.

Branching Diagrams Branching diagrams show the close evolutionary relationships between organisms. As characteristics differ, branches in the diagram form.

Cladograms

5 Kingdoms of Organisms Bacteria (Monera) Archeabacteria Eubacteria Protists Fungi Plants Animals

Bacteria (Monera) http://www.ric.edu/faculty/ptiskus/six_kingdoms/ : Archeabacteria: Single celled (simple) Found in extreme environments like hot boiling water; oceans; salt marshes Eubacteria: Very common and found everywhere. Streptococci  (strep throat)

Protists http://www.ric.edu/faculty/ptiskus/six_kingdoms/ Single Celled Complex Cells Protozoa and algae are protists. Sometimes they are called the odds and ends kingdom because its members are so different from one another. Protists include all microscopic organisms that are not bacteria, not animals, not plants and not fungi.

Fungi http://www.ric.edu/faculty/ptiskus/six_kingdoms/ Most fungi are multicellular and consists of many complex cells Fungi cannot make their own food. Examples: Mushrooms Mold Mildew Some fungi taste great and others can kill you!

Plants http://www.ric.edu/faculty/ptiskus/six_kingdoms/ Plants are all multicellular and consist of complex cells With over 250,000 species, the plant kingdom is the second largest kingdom. Examples: Flowering plants Mosses Ferns Plants make their own food using energy and sunlight. Without plants, life on Earth would not exist! Plants feed almost all the heterotrophs (organisms that eat other organisms) on Earth. Wow!

Animals http://www.ric.edu/faculty/ptiskus/six_kingdoms/ The animal kingdom is the largest kingdom with over 1 million known species. All animals are multicellular and consist of many complex cells. Animals are heterotrophs. (organisms that eat other organisms.)

Seven Levels of Classification Today’s classification system uses several levels to classify organisms. The more characteristics that organisms have in common, the more level they share. Kingdom Phylum Class Order Family Genus Species

Kingdom (Broadest/Largest) Subdivisions King Philip Came Over For Good Spaghetti Kingdom (Broadest/Largest) Phylum Class Order Family Genus Species (Most specific/Smallest)

Levels of Classification http://www. ric Sumatran Tiger Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Family: Felidae, Genus: Pathera, Species: tigris

VERTEBRATES All animals WITH a Backbone are called Vertebrates. 5 Vertebrate Groups: Amphibians: Frog, Toad, Salamander Birds: Eagle; Cardinal, Robin Fish: Goldfish, Clownfish, Shark Mammals: Lion, Dogs, Humans, Whales Reptiles: Snake, Lizard, Alligator

INVERTEBRATES All animals WITHOUT a Backbone are called Invertebrates. Groups of Invertebrates Ocean Invertebrates: Jellyfish, Coral, Sponges Worms Arthropods Insects: Ant, ladybug, honey bee, grasshopper Crustaceans: Lobster, Crab, Shrimp Spiders and Scorpions