1. Classification Classification process of grouping organisms according to shared physical characteristics. Modern Classification is based on EvolutionModern Classification is based on Evolutionary relationships Modern Classification is based on Evolution

2. I. How was all life grouped for study? A. Aristotle lived in 384-322 B.C. and is credited with the first classification system. He grouped all living things into two basic groups: plant and animal. OR

3. “Father of Taxonomy” B. Carolus Linnaeus lived in 1707-1778 1. He classified each organism into 7 hierarchical (largest to smallest) groups. We still use this system today. The Domain was added recently.

5. 2. He also gave each one a unique two part name using Latin, because Latin was no longer spoken and thus was less likely to change. He used the two most specific groups: the genus and species. He used the two most specific groups: the genus and species. EX: the dog is Canis familiaris and the wolf is Canis lupus. and the wolf is Canis lupus. Rule: the genus is capitalized and the species begins with a lower case letter! Both are italicized or underlined. Both are italicized or underlined. Homo sapien is the scientific name for a human Genus= Homo species= sapien

6. 3. Linnaeus’ two name naming system is called binomial nomenclature. Every organism was given a two- word name, using the genus and species. This is called it’s “scientific name”. 4. The benefit of binomial nomenclature was to eliminate confusion of common names (ex. cottonmouth and water moccasin are actually the same animal) and allows scientists around the world to communicate easily. What name do you use for this organism?

7. C. With the invention of the microscope unicellular creatures were discovered. Eventually two kingdoms became 5 D. As knowledge of the diversity of organisms increased, 5 kingdoms became 6 kingdoms. With new technology the science of classification can and DOES change!

9. E. The science of naming and classifying organisms is called taxonomy. It assigns seven classification groups or taxa. To remember the order from largest to smallest:

10. OR…

11. Other Helpful ways to remember the order of the 7 levels King Philip Came Over For Grape Soda. King Philip Came Over For Grape Soda. King Philip Came Over For Green Skittles. King Philip Came Over For Green Skittles. Kings Play Chess On Fat Green Stools. Kings Play Chess On Fat Green Stools. Katy Perry Came Over For Good Soup. Katy Perry Came Over For Good Soup.

12. 1. The kingdom is the broadest and most general of these taxa, and contains the greatest number of organisms that are the least related to one another. 2. Species is the most specific and contain only one type of organism. The species taxon has the most related individuals. A species is defined as a group of organisms which can interbreed and produce fertile offspring. https://www.youtube.com/watch?v=DVouQRAKxYo&t=21s

14. species class order genus family phylum kingdom What are the taxons from largest to smallest? Write them on circle starting from the outside Each larger group contains many smaller groups: A Kingdom contains many different phyla (singular) A genus contains many different species:

15. F. Today, we use three domains, which is divided into six kingdoms. These domains are based on new DNA information about possible evolutionary relationships.

18. 1.Which level is the most general? The most specific? 2.At what taxonomic level do the dog and human become different? 3.What is the family name of the dog? 4.Which organism is most closely related to the dog? 5.What is the scientific name of the dog? 6.A genus is composed of a number of related? 7.A group of related phyla are? 8.Which taxon contains the largest # of organisms?

19. Classification Tools Dichotomous keys Dichotomous keys Cladograms Cladograms Phylogenic trees Phylogenic trees

20. II. What happens when you find an organism and you want to identify it? A. Dichotomous key is a series of descriptions arranged in pairs that lead the user to the identification of an unknown organism. Adichotomous key is only useful if the organism has already been classified and given a scientific name. A dichotomous key is only useful if the organism has already been classified and given a scientific name. https://www.youtube.com/watch?v=wpKulkADzBk

21. 1. Always start at statement 1 (or the beginning point) 2. Decide which path best describes the organism (Statement A or Statement B) 3. Follow that path to find the next choice (Go to …) 4. When you can go no further, you will identify the organism!

23. B. If the organism has NOT been classified, taxonomists must begin the process of classification. In order to correctly classify an organism, scientists use many modern tools: 1. Morphology describes the physical characteristics of an organism. This is used to place the organism within a domain and kingdom. Example: Presence of a nucleus places the organism in Domain Eukarya Ability to make your own food and be multicellular places you in the kingdom Plantae

24. 2. DNA and biochemical analysis allow scientists to test less visible characteristics such as chemical makeup of a cell wall or the type of enzymes you have. Example: Gram staining a bacteria cell allows scientists to distinguish between archaea and prokarya. Gram-positive anthrax bacteria (purple rods) in cerebrospinal fluid sample. If present, a gram- negative bacterial species would appear pink. (The other cells are white blood cells)anthrax cerebrospinal fluidwhite blood cells Gram-negative E. Coli bacteria.

25. 3. Comparing embryology allows scientists to group organisms that share a common early fetal development. Example: The diagram below would suggest the last two organisms are most closely related.

26. 4. Evolutionary phylogeny describes the evolutionary relationships between organisms. These relationships are deduced based on shared traits that may have been passed from ancestor to new species. Traits may include physical traits (ex. presence of jaws), or may be genetic traits (shared genes). These relationships can be illustrated in a phylogenetic tree or cladogram: How to Build a Cladogram How to Build a Cladogram

27. Interpreting Cladograms Cladistics is a method of classifying organisms into groups of species called clades (from Greek ‘klados' = branch) Each clade consists of an ancestral organism and all of its evolutionary descendants Members of a clade will possess common characteristics as a result of their shared common ancestor Clades can be organized according to branching diagrams (cladograms) in order to show evolutionary relationships

28. Interpreting Cladograms each branch point represents the splitting of two new groups from a common ancestor Each branch point (node) represents a speciation event by which distinct species are formed Cladograms show the probable evolutionary history The closer the two groups are in a clade the more closely related they are expected to be

29. Interpreting Phylogenetic trees A phylogeny, or evolutionary tree, represents the evolutionary relationships among a set of organisms, called taxa (singular: taxon). "phylogenies" represent true evolutionary history. in a "phylogeny," the branch lengths indicates the amount of change or time