1. Chapter 22 Evidence for Evolution How has evolution risen in status to the level of THEORY, the same level as gravity or plate tectonics? Through repeated observations from many areas of life sciences.

2. Evidence of Evolution What is probably the first evidence that living things have changed over time? What additional clues have been added since then?

3. Beaks as Evidence Darwin saw finches on the Galapogos Islands (and tortoises, and armadillo fossils in South America, and lots more). What did he notice about these finches? “ …from an original paucity of birds in this archipelago, one species has been…modified for different ends.” see page 455 Can someone rephrase this? Are you able to see things in a different way than they have traditionally been seen?

4. Industrial Melanism Peppered moth story See peppered moth sim See details of how the experimental method was implemented (pg 456) (mark/ recapture). How does this relate to the Clean Air Act? What types of selection can you attribute this to?

5. Artificial Selection There are some dramatic examples of artificial selection to be found on page 458-- 459. Give 2 examples and include details.

6. Selection Ponderables Does selection act on genotypes or phenotypes? Which is more likely to be selected against, deleterious mutations that are dominant or those that are recessive? Why? Can selection create perfect organisms? –(Human’s backs are evolved from 4-legged ancestors and not fully compatible w upright posture, so many older people have backpain)

7. Evolution of Horses Compare the profile of the house cat with the early horse on page 462. What climatic conditions accompanied the change the feet and teeth of horses?

8. Fossil Evidence How can the age of fossils be determined? –Relative Dating –Absolute Dating

9. Fossil Evidence We found orange juice with 1/8 of its original 32 P in the lab cabinets during cleanup. 32 P has a half-life of about 14 days. How long had the orange juice been there? That is 3 half-lives, so about 3 x 14= 42 days. Drink Up!

10. Anatomical Evidence Homologous structures –Structures that have different functions but arrived from same body part. –Human arm, bat wing, porpoise flipper Development –“Ontogeny recapitulates phylogeny”. –Developing embryo tells a story gill pouches, tail, fur (lanugo)

11. Anatomical Evidence Did you know there are pelvic bones in snakes? In whales? Why? –Vestigial structures What vestigial structures do humans have? –Appendix

12. What our new understanding of genetics tell us about our model of evolution?

13. Molecular Record The more amino acid (or DNA base pair) differences, the greater the evolutionary distance. The ‘trunk’ of the tree represents similar traits or molecules (depending on how tree was made). Each branch represents a divergence. (See page 466)

14. Convergent Evolution Two separate groups (branches on evolutionary tree) display similar characteristics. Ex: Placental mammals often have a marsupial “cousin”: wolf / tasmanian “wolf”.

15. Island Evolution An ideal location to study evolution. Organisms can be seen that are similar to the mainland species that they are nearest, but with traits adapted to a specific island.

16. Response to criticism Discuss one criticism/ response.