3. Defined: Collection of every known fossil Most fossils found in sedimentary rock Age determined by depth –Law of Superposition: new rock forms on top of older rock Evidence Conclusions: –1) Newer fossils are more complex –2) Common ancestors: similarities between ancient & modern life

5. Comparing old fossil to modern life shows change Ancient Kelp Modern Kelp

6. Radiometric Dating Helps determine age of fossils Isotopes: atoms of the same element with differing neutrons –Ex: 12 C and 14 C 12 C = 6 protons + 6 neutrons 14 C = 6 protons + 8 neutrons When organism dies: 14 C starts to decay Fossil age determined by comparing ratio of 12 C to 14 C Both are Carbon

8. Timelines like this are accurate, but the scale of time it too massive for us to visualize…So let’s try a different scale of time

9. 24 Hour Life Timeline Scale: 1 minute = 3 million years This timeline shrinks Earth’s existence to a 24 hour day. We all can visualize 24 hours.

10. Fossils show that the oldest life is ~3.5 byo…bacteria

11. Bacteria (3.5 billion) 24 Hour Life Timeline Scale: 1 minute = 3 million years

12. Fossils show the first vertebrates (fish) lived ~510mya.

13. Fish (510 million) 24 Hour Life Timeline Scale: 1 minute = 3 million years Bacteria (3.5 billion)

14. Fossils show the first land animals (amphibians) lived ~340mya

15. Amphibians (340 million) 24 Hour Life Timeline Scale: 1 minute = 3 million years Bacteria (3.5 billion) Fish (510 million)

16. Fossils show that reptiles first lived ~310mya

17. Reptiles (310 million) 24 Hour Life Timeline Scale: 1 minute = 3 million years Bacteria (3.5 billion) Fish (510 million) Amphibians (340 million)

18. Fossils show that mammals and dinosaurs first lived ~250mya

19. 24 Hour Life Timeline Scale: 1 minute = 3 million years Dinosaurs & mammals (250m) Bacteria (3.5 billion) Fish (510 million) Amphibians (340 million) Reptiles (310 million)

20. Fossils show that flowering plants and birds first lived ~175mya

21. 24 Hour Life Timeline Scale: 1 minute = 3 million years Bacteria (3.5 billion) Amphibians (340 million) Fish (510 million) Reptiles (310 million) Dinosaurs & mammals (250m) Flowers and birds (175 m)

22. Fossils show that humans first lived ~200,000 years ago

23. Humans (200,000) 24 Hour Life Timeline Scale: 1 minute = 3 million years Bacteria (3.5 billion) Amphibians (340 million) Fish (510 million) Reptiles (310 million) Dinosaurs & mammals (250m) Flowers and birds (175 m) 1 second = 50,000 years So if humans have been around for 200,000 years, how many seconds before midnight did we evolve?

24. Humans (200,000) Other Notable Events Scale: 1 minute = 3 million years Bacteria (3.5 billion) Amphibians (340 million) Fish (510 million) Reptiles (310 million) Dinosaurs & mammals (250m) Flowers and birds (175 m) Unicellulareukaryotes First plants (aquatic) Dinosaurs extinct Obvious conclusion: Life began very simple and gradually became more complex

25. AKA: Transition Fossils –Archaeopteryx: shares both bird & reptile features –Basilosaurus: shares whale & land mammal features –Tiktaalik: shares fish & amphibian features Evidence Conclusion : Indicates common ancestry Reptile Evidence Teeth Bony tail Bird Evidence Wishbone Feathers Whale Evidence Long spine Found in dried up oceans Land Evidence Wolf-like teeth Hind legs Fish evidence Scales Fins Found in dried-up oceans Amphibian evidence Eyes on top of head Wrist bones

26. Defined: similar body structures with very different functions Different environments lead to adaptations –Ex: The forelimbs of animals Evidence Conclusion : Indicates common ancestry

27. Defined: Organs which have lost most or all their original function Vestigial Human Parts: –Gill slits = once used to breath oxygen in water –Yolk sac = once used to nourish developing embryo –Tailbone = once used for balance –Appendix = once used to digest plants –Wisdom teeth = once used to grind plant tissue Evidence Conclusion : Indicates common ancestry

28. Human Embryo w/ Vestigial Structures

29. Pythons have tiny femurs (leg bone)

30. DNA, RNA, proteins compared Genetic code same for most life More related species have more similar biochemistry Evidence Conclusion : Indicates common ancestry

31. Different species show similar development patterns Different body plans become noticeable later in development Evidence Conclusion : Indicates common ancestry

32. Antibiotics: drugs designed to kill bacteria –Obtained from fungi Antibiotic Resistance: Bacteria are adapting to the use of antibiotics –Misuse of antibiotics speeds up the process –Importance: Bacteria infections are becoming harder to treat –Example of natural selection Fungus Bacteria

34. Antibiotic Resistance GoodBad The antibiotics kill the bacteria, so the area around them are clear The antibiotics don’t kill the bacteria, that’s why there is no clear area around them.

36. Pesticides –Chemicals designed to kill pests (rodents, insects, etc…) –Pesticides sprayed on crops to kill pests Pesticide Resistance: pests are adapting to the use of pesticides –“Strong” pests survive to reproduce –Importance: Crops are being destroyed by pests

38. First life on earth were prokaryotes (bacteria) Changing environments lead to adaptation Much evidence indicates life has common ancestors