2. Study of evolutionary relationships Evidence shows all life evolved from a single, common ancestor

3. A method that applies the scientific method to the construction of evolutionary relationships

4. Diagram showing how organisms are related base on shared, derived characteristics Characteristics that appear in recent parts of a lineage but not in its older members More shared derived characters = more closely related/more recent common ancestor = derived characteristics

5. With current DNA sequencing techniques, cladograms show amazing relationships Ex: evolutionary history of whales Prior to DNA technology, fossil evidence suggested that whales were closely related to an extinct group of mammals called the mesonychids Today, we know that the origin of whales is better represented by the tree on the right. Whales and hippos are closely related! DNA evidence caused paleontologists to re-evaluate their interpretations of the fossil evidence, leading to a revision of our understanding of the evolutionary relationships in this group

6. Ingroup A group of species we are interested in Ex: chimpanzee to humans and gorillas Outgroup A species that is most closely related to an ingroup Ex: baboon to chimps, humans and gorillas Node The point at which species diverge Ex: A, B, C in diagram

7. Cladogram video

8. Primate Cladogram

10. 1.Determine characteristics to analyze 2.Analyze characteristics of species 3.Build your cladogram! a.The species with the fewest shared derived characteristics is your outgroup b.Follow the rule of maximum parsimony (the shortest number of steps or character state changes is most likely correct)

11. Copy and complete the table below (mark “x” if an organism contains the character, leave the box blank if it does not): Derived Characters in Organisms Organism Derived Character BackboneLegsHair Earthworm Trout Lizard Human

12. Construct your cladogram!

13. Organism with the least number of traits goes at the bottom (less related to the rest) Organism with the most traits goes at the top (more related to the rest)

14. Add the derived characters (traits) where appropriate Earthworm Trout Lizard Human Backbone

15. Earthworm Trout Lizard Human Backbone Legs Hair