PHYLOGENETIC TREE CLASSIFICATION AND TAXONOMY BIOLOGY 11 CLASSIFICATION
CLASSIFICATION AND TAXONOMY BIOLOGY 11
CLASSIFICATION • Grouping of objects or information based on similarities • Biological Classification- how biologists group and categorize extinct and living species • Taxonomy is the field of biology concerned with identifying and classifying organisms
WHO AM I? • • I walk on all fours. My body is stout with an arched back. My body sparsely covered with coarse hairs. My ears are disproportionately long, and my tail is very thick at the base and gradually tapers I have an elongated head. My mouth is small and tubular. I like to dig with big sturdy claws. Each toe bears a large, robust nail which is somewhat flattened and shovel-like, and appears to be intermediate between a claw and a hoof
WHY CLASSIFY? • There are many different systems with obscure names for animals… some based on physical and behavioural characteristics • Some scientists would look at that same animal and describe it differently, making it nearly impossible to identify any organisms • Imagine going shopping in a grocery store that had no system for organizing food into categories… how long would it take for you to find something?
WHY IS A SYSTEM OF CLASSIFICATION NEEDED? • • Organize species into groups and discuss them Show relationships between organisms Identify new organisms and keep track of them Accurately and uniformly name organisms • Prevents misnomers such as “starfish” and “jellyfish” that aren’t really fish. “Seahorse” is not a horse. • Humans are Homo sapiens • Uses same language (latin) for all names
EARLY TAXONOMY Aristotle was the first taxonomist dividing organisms into land, sea, & air dwellers Linnaeus developed the modern system of naming known as binomial nomenclature. Linnaeus grouped species according to shared physical characteristics
BINOMIAL NOMENCLATURE • Each organism has a two-part Latin name • The first half is the GENUS, which is common to several species, and the second half is the SPECIES name, unique to that particular organism. • Ex. All chickadees are in the Genus Pocile while individual types of chickadees will have their own species name like atricapillus. Scientifically, a Black-capped chickadee will be called an Pocile atricapillus. • The two-part name is called the scientific name.
Poecile atricapillus Poecile rufescenes
RULES FOR NAMING ORGANISMS • Using binomial nomenclature • Genus name + species name • Genus name is capitalized, species name is not • Both names are in italics or underlined (if handwriting)
• Examples: Homo sapiens (Humans) • Felis catus (House Cat)
TAXONOMY • The science of naming and assigning organisms to groups • Groups of similar organisms are called taxa (singular taxon) • There are EIGHT taxa within taxonomy
• Domain Very large/general group of organisms • Kingdom • Phylum • Class • Order • Family • Genus • Species Very small/specific group of organisms
USE YOUR CELL! • Using your cell phone, find the Taxons for one organism we have not talked about • Examples- Kangaroo - Gold fish - Wild Rose - Kiwi - Douglas Fir Tree
EXAMPLE OF CLASSIFICATION • • Domain: Eukarya Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primata Family: Hominidae Genus: Homo Species: sapien • Scientists would use the term Homo sapien to refer to humans. In latin Homo sapien means “wise man”.
• These groups can be remembered using several mnemonics, for instance: • KINGDOM, PHYLUM, CLASS, ORDER, FAMILY, GENUS, SPECIES • Kids Play Catch Over Farmer Green’s Stable. • King Phillip Came Over For Good Spaghetti.
MODERN 6 KINGDOM TAXONOMIC SYSTEM
KINGDOM MONERA DIVIDED • All prokaryotes belong to the kingdom Monera • Includes both Eubacteria and Archaebacteria • Archaebacteria live in harsh environments like very salty lakes; intestines of mammals; and hot, sulfur springs & may be autotrophs or heterotrophs • Eubacteria are “true” bacteria some of which cause disease
PROKARYOTE VS EUKARYOTE
PLEASE MAKE A CHART
KINGDOM EUBACTERIA AND ARCHAEBACTERIA
KINGDOM PROTISTA • Includes unicellular and a few simple multicellular eukaryotes • They have nuclei and membrane-bound organelles • Some are “plant-like”, some are “animal-like” • They may be autotrophic (ex. Euglena) or heterotrophic (ex. Amoeba)
KINGDOM FUNGI • Include mushrooms, molds, mildews, yeast and many relatives • They are eukaryotic • They are absorptive heterotrophs - they digest food using enzymes & then absorb it • Fungi act as decomposers or parasites in nature
KINGDOM PLANTAE • Stationary, autotrophic, multicellular, eukaryotes that photosynthesize and produce oxygen • Plantae include mosses, ferns, cone-bearing plants, and flowering plants
KINGDOM ANIMALIA • Multicellular, eukaryotic and heterotrophic (that is, they rely on other organisms for their nourishment) • Most members can move from place to place • Include fish, birds, reptiles, amphibians, and mammals - also includes sponges, jellyfish, several phyla of worms, sea stars, insects and a host of other organisms
• Crash Course: Taxonomy: Life’s Filing Cabinet • Questions • • Pg. 320 # 1 Pg. 323 # 2, 3 Pg. 325 # 3 Pg. 329 #1 -3
HOW ARE RELATIONSHIPS DETERMINED? • Phylogeny - Evolutionary history or similarities between modern and fossil organisms • Behavioral - similar behavioral patterns • Geographical - location of the species on earth • Development - similarities in developmental stages • Biochemistry - closely related species have similar DNA and similar chromosomal structure as well as similar proteins (eg. both humans and cats produce lactose, lizards do not)
COMPARING HUMAN PROTEINS TO OTHER PRIMATES • For each primate listed, determine how many amino acids differ from the human sequence. Record those numbers. • Calculate the percent difference by dividing those numbers by 15 and multiplying by 100.
• Which primate is most closely related? Least closely related? • Construct a diagram of primate evolutionary relationships that most closely fits your results.
PHYLOGENY- EVOLUTIONARY HISTROY • Phylogenetic trees are branching diagrams showing how organisms are related • Organizes living things based on their evolution • Common ancestor is shown at the base of the tree - most modern organisms shown at tips of branches • Each time a branch divides into a smaller branch, it represents speciation
CLADOGRAMS • Show relations based on characteristics such as feathers, hair, scales, etc.
• http: //ccl. northwestern. edu/simevolution/obonu/cladogra ms/Open-This-File. swf
CLADOGRAM MINILAB • With a partner, complete the cladogram mini lab • Take 10 -15 minutes to complete all questions • Be prepared to share your answers with the class
DICHOTOMOUS KEY • Allows the user to determine the identity of items in the natural world, such as trees, wildflowers, mammals, reptiles, rocks, and fish. • Keys consist of a series of choices that lead the user to the correct name of a given item. • Always give two choices in each step.
WHEN CONSTRUCTING, KEEP IN MIND: • Questions must have a yes or no answer • Use constant characteristics rather than variable ones. • Use measurements rather than relative terms like "large" and "small". • Use characteristics that are available to the user of the key • Make the choice a positive one - something "is" instead of "is not".
WHAT ELSE COULD HAVE BEEN USED TO SEPARATE THESE ORGANISMS?
ACTIVITY: MAKING A DICHOTOMOUS KEY
EVOLUTION CONCEPT MAP • A concept map is used to show the relationships between different ideas • Use your Learning Outcome sheets for Evolution and Taxonomy and create a concept map • Use all main ideas and vocab words on your maps • Where ideas are connected, provide reasoning on arrows.