1. Classification

2. Why do we classify living things? We have over 1.5 million NAMED & classified species. There may be over 30 million species on Earth!! We organize so we can communicate, share information & find information.

3. Taxonomy …branch of biology for naming & grouping of organisms Can be grouped according to: 1) their characteristics 2) their evolutionary history

4. History of taxonomy Aristotle – had 2 groups, plants & animals Linnaeus – developed a Hierarchy of levels, according to morphology (physical appearance)

5. Problems with using morphology to classify 1)Some things may look different but still be a member of the same species. 2)Injuries or other events may alter the physical appearance 3)Some things look alike but are not related (dolphins & fish)

6. Hierarchy of taxonomy

7. Domain (New level, there are 3 domains; Archaea, Bacteria & Eukarya) Kingdom (There are 6 kingdoms) Phylum Class Order Family Genus Species

8. Binomial Nomenclature …is the ”2 part scientific name” of an organism RULES 1) 1 st word = genus name, always capitalize 1 st letter 2) 2 nd word = species name, all lower case 3) italicized or underlined 4) Written in Latin

9. Which is written correctly? a) Homo sapien = humans b) Pipa pipa = surinam toad c) P. leo = lion

10. Phylogeny..classifying organisms according to their evolutionary history A phylogenetic tree can be created using systematics.

12. How does Systematics work? Use evidence from many sources: 1) fossils 2) morphology (physical appearance) 3) embryological development 4) chromosomes & DNA

13. Cladistics …classifies organisms according to the order that they diverged from a common ancestor. Shown using a cladogram

14. Example of a cladogram