Chapter 18: Classification
Classification of 2 different organisms Red Maple Kingdom: Plantae Phylum: Anthophyta Class: Dicotyledones Order: Sapindales Family: Aceraceae Genus: Acer Species: Acer rubrum Human Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primata Family: Hominidae Genus: Homo Species: Homo sapiens
I. Classification A. How Classification Began 1. Classification - grouping of objects or information based on similarities 2. Taxonomy - branch of Biology that deals with the grouping and naming of organisms. 3. 2000 years ago Aristotle - Greek philosopher; developed first classification system - Two major groups: plants (herbs, shrubs, trees) & animals (live on land, in air or water)
Binomial nomenclature – 2 name naming system 4. 1707 – 1778 Carolus Linnaeus - Swedish botanist who developed system of classification that is still used today - based on close relationships of organisms. Binomial nomenclature – 2 name naming system Genus & species italicized or underlined Genus name is capitalized and species is lower case Ex: Homo sapiens Genus - a group of closely related species species - population of interbreeding organisms capable of producing fertile offspring
Why use scientific names??? Common Names usually have regional (location) differences Dolphin… dolphin fish… mahi mahi… porpoise… Huh???
Mountain Lion? Cougar? Puma? Puma concolor
Confusion in Using Different Languages for Names Common Names
Latin Names are Understood by all Taxonomists Scientific Name
Binomial Nomenclature Common Name Scientific Name
B. Taxonomy- the study of classification Why classify? EASE OF COMMUNICATION *We need a universal system of naming organisms so that the scientists around the world know they are studying the same organism 2. EASE OF IDENTIFICATION *It is a useful tool when trying to identify diseases or pathogens quickly – Ex: poisonous vs. non-poisonous mushrooms 3. PROTECTING SPECIES *Provides economic/ ecological advantages when a particular species produces something useful – Ex: the Pacific Yew produces taxol which may be used in treating some forms of cancer.
C. How Living Things are Classified 1. Taxonomic categories - a hierarchy taxon (taxa-plural): Kingdom, Phylum, Class, Order, Family, Genus , species Taxon- group or level into which organisms are classified King Phillip Came Over For Grape Soda
II. The six Kingdoms EX: E. coli, Salmonella, Staphylococcus aureus Kingdom Eubacteria - True bacteria - prokaryotic (no nucleus or organelles), unicellular decomposers or photosynthetic EX: E. coli, Salmonella, Staphylococcus aureus
B. Kingdom Archaebacteria - Prokaryotes, unicellular, microscopic, thrive in extreme environments like salt, lakes, swamps & hot springs. Thought to most closely resemble first life on Earth! Ex: Methanogens, extreme halophiles Bacteria Of Boiling Hot Springs In Yellowstone National Park Black Smokers on ocean floor
C. Kingdom Protista - unicellular and multi-cellular organisms that are either plant-like, animal-like or fungus-like. Eukaryotic and usually live in moist environments. Red Algae Amoeba Radiolarian Paramecium Diatom Giant Kelps
D. Kingdom Fungi - Mostly multicellular (yeast are unicellular), heterotrophic, chitinous cell walls, eukaryotic, absorbs nutrients obtained by decomposing dead organisms or waste/ detritus (detritivores/ saprobes). Once classified with Plantae. Mushrooms Yeast Bracket Fungi
E. Kingdom Plantae - eukaryotic with cell walls of cellulose, multicellular, stationary, autotrophic, producers
F. Kingdom Animalia - Multicellular heterotrophs, eukaryotic, no cell walls, and most with highly organized tissue and organ systems.
Kingdoms of Life Activity Use your notes and textbook to complete the Kingdoms of Life Chart (10 minutes) Finish the WS for HW
Autotroph or heterotroph Cell Structures Cell walls with peptidoglycan Domain: Bacteria Domain: Archaea Kingdom Eubacteria Archaebacteria Mode of Nutrition Autotroph or heterotroph Cell Structures Cell walls with peptidoglycan Cell walls w/o peptidoglycan
Domain: Eukarya PROTISTA FUNGI PLANTAE ANIMALIA Autotroph or heterotroph Heterotroph Autotroph Some have Cell walls of cellulose, some have CW of silica Cell walls of chitin Cell walls of cellulose No cell walls
How Are Relationships Determined? 1. By Evolutionary History (classification) 2. By Development 3. By Biochemistry 4. By Behavior 5. Cladistic Analysis
D. How Are Relationships Determined? 1. By evolutionary history (classification) - common ancestors, studying modern day life-forms and comparing them with fossils (ancestors) *Phylogeny - The evolutionary relationship of a species 2. By development - examining the development stages of animals for similarities to determine their relationships and phylogeny *Ontogeny – the origin and development of a species 3. By Biochemistry - examining composition in DNA & proteins, more sequences in common mean more closely related. DNA analysis is studying “Molecular Clock” 4. By Behavior - noting similarities in behavioral patterns 5. Cladistic Analysis- classifying based of derived characters (appear in recent lineages) *Cladogram AKA Phylogenetic Tree
Cladogram Watch this video A derived character
Cladogram = Diagram showing how organisms are related based on shared, derived characters such as feathers, hair, or scales Primate Cladogram
It can be helpful to assign letters or symbols to the derived characters in order to draw a clear cladogram
The Great Clade Race Each runner in the race starts at the same point (the starting line) The course works its way through a forest to the other side (runners can choose different pathways) Each runner has a card that they get stamped at different checkpoints throughout the course (runners will only have the same stamp if they went through the same checkpoint) You will be able to determine the layout of the course and which path each runner took by looking at the stamps that each runner received
Whiteboard assignment Draw the course & Label The checkpoints Where the runners left the forest Questions to think about Think about the Great Clade Race as an analogy for evolution What do each of the following represent: Runners Checkpoints The Race Course
Discussion Questions Describe the analogy between evolution and this activity. Runners Checkpoints The Race Course Could you tell which path went left or right? Could you tell how long each segment was? In the biological case, why are organisms on different paths? What do the forks in the road mean? Can organisms lose stamps in nature?
MEG JIM PETER MICHAEL PAM CHRIS LOIS DWIGHT
Extension Thinking in the biological sense, how would this card change your course
MEG JIM PETER MICHAEL PAM CHRIS LOIS 9th DWIGHT Why would this happen?
Extension Thinking in the biological sense, how would this card change your course
MEG JIM PETER MICHAEL PAM CHRIS LOIS 9th DWIGHT Why would this happen?
Examples of Cladograms