1. Classification of Living Things

2. Why do we classify things?  Supermarket aisles  Libraries  Classes  Teams/sports  Members of a family  Roads  Cities  Money

3. What is classification?  Classification: putting things into orderly groups based on similar characteristics  Taxonomy: the science of describing, naming, and classifying organisms according to their characteristics and evolutionary history

4. Early classification  Aristotle grouped everything into simple groups such as animals or plants  He then grouped animals according to if they had blood or didn’t have blood, and if they had live young or laid eggs, and so on…

5. Modern Classification System  Developed by Carolus Linnaeus  Swedish Biologist 1700’s  Grouped organisms into hierarchical categories  Starts broad and ends specific

6. Modern Taxonomy The Evidence used to classify into taxon groups  1) Embryology  2) Chromosomes / DNA  3) Biochemistry  4) Physiology  5) Evolution  6) Behavior

7. The modern system of classification has 8 levels:  Domain  Kingdom  Phylum  Class  Order  Family  Genus  Species

11. Helpful way to remember the 8 levels  Dumb kids playing catch on freeways get squashed  Or…make up your own…  D K P C O F G S

12. Scientific Names: Binomial Nomenclature  An organism’s genus is always written first; the organism’s species is always written second  The genus is Capitalized; the species is written in lower case Homo sapiens

13. Representing Evolutionary Relationships: Phylogenetic Tree: - Family tree showing evolutionary history - shows relationships thought to exist between groups or organisms

17. Representing Evolutionary Relationships: Cladogram: - Uses shared derived traits - Derived traits indicate divergence from a common ancestor