Classification of Organisms

1. Classification of Organisms

2. Dichotomous Key • A dichotomous key is a method for determining the identity of something by going through a series of choices that leads the user to the correct name of the item • At each step of the process of using the key, the user is given two choices; each alternative leads to another question until the item is identified. (It's like playing 20 questions.)

3. Tree Style Dichotomous Key This is the style we will be making

4. Dichotomous Key for Candy • This style is common in identification books. • Use this style in the homework Note: “scientific names” are made up here.

5. A Dichotomous Key for Sharks Note: real scientific names here

6. Binomial nomenclature • Over 2,000 years ago Aristotle categorized living things by their appearances into plants and animals • He came up with a two-part name for each organism. • This was the first Binomial nomenclature: a classification system in which each species are assigned a two-part scientific name

7. Linnaeus • In the 1750’s Carolus Linnaeus expanded on the binomial nomenclature idea and devised a systematic method in which each species had its own unique binomial nomenclature Two-part name

8. Linnaean Classification • Linnaeus knew that the names needed to be universal • He used Latin because it is a dead language. • This means that it is not used as ordinary spoken languages for everyday communication and therefore does not change.

9. Aristotle Who invented the first classification system based on a two part name? What is this two-part style classification system called? Binomial nomenclature Who refined this by creating a systematic method in which each species had its own unique binomial nomenclature? Linnaeus

10. Scientific Names • This is the system we use today. • The first part of the name is the genus to which it belongs; it always starts with a capital letter • The second part of the name is a description. Traditionally, a physical description, where it is from or first found, or named after someone; it is written in all lower case letters • The whole scientific name is always italicized or underlined When hand written

11. Scientific Names together uniquely identify each species • Example: Genus second term Sometimes you will see this abbreviated. Example: T. aculeatus Tachyglossus aculeatus Still italicized! Common name: Short-beaked echidna

12. What is the first part of the scientific name? the genus to which it belongs The scientific name of this animal is written incorrectly. How would you make it correct? puma concolor Puma concolor or Puma concolor When hand written Common names: mountain lion, puma, panther, painter, mountain cat, or catamount

13. Taxa: Rank-Based Classifying • Linnaeus expanded on this grouping system to include a hierarchy of more distantly related organisms until all organisms were encompasses

14. Taxa: Rank-Based Classifying • Eventually there were seven hierarchical levels to which we call taxa(plural) or taxon (singular) • Let’s follow an example through the various levels…

15. Procyon lotor Common Name: Raccoon Species Genus Family Order Class Phylum Kingdom

16. Procyon lotor Common Name: Raccoon Procyon Species Genus Family Order Class Phylum Kingdom Crab-eating raccoon

17. Procyon lotor Common Name: Raccoon Procyon Species Genus Family Order Class Phylum Kingdom Procyonidae Kinkajou Olingos Raccoon Nasuella Bassariscus Chapalmalania Nasua

18. Procyon lotor Common Name: Raccoon Procyon Species Genus Family Order Class Phylum Kingdom tiger Procyonidae brown bear Carnivora spotted hyena grey wolf African civet wolverine

19. Procyon lotor Common Name: Raccoon Procyon Species Genus Family Order Class Phylum Kingdom Procyonidae Carnivora Mammalia Orangutan and Human (babies)

20. Procyon lotor Common Name: Raccoon Procyon amphibians Species Genus Family Order Class Phylum Kingdom Procyonidae fish Carnivora Mammalia reptiles (including birds) Chordate tunicates

21. Procyon lotor Common Name: Raccoon Procyon Species Genus Family Order Class Phylum Kingdom Procyonidae Carnivora Mammalia Chordate Animalia

22. Memorize this list!!!!! Kings play chess on fat guys stomachs.

23. Kentucky Plants Can Originate From Good Soil

24. Taxonomy Describes Evolutionary History • As new technologies (such as DNA mapping) are developed these groups are refined • Many biologists now use a three domain addition based on DNA and molecular evidence. Bacteria Archaea Eukarya You need to know these!

25. What domain are humans in? Eukarya What are the other two domains? Bacteria & Archaea

26. Phylogeny • Phylogeny: the study of how living and extinct organism are related to each other • Clade: A group of species that includes their single common ancestor and all descendents of that ancestor. • Scientists use Cladistics to build phylogenies

27. Examples of Cladograms Don’t let this trip you up! This is only a different style!

28. Two different clades because of which common ancestor is included Common ancestor for each clade

29. Common ancestor for clade

30. Common ancestor for clade

31. Common ancestor for clade

33. Lizards & Snakes Mammals Crocodiles Amphibians Turtles Fish Birds “Reptiles” are not a clade unless we include birds