1. Natural Selection & Change over time

2. Charles Darwin British naturalist Sailed on the HMS Beagle around the world Collected and recorded all the different species and fossils he came across Wanted to explain biodiversity

3. Darwin at the Galapagos The Galapagos islands have many different biomes – Hot and dry like the desert – Rainy and full of plants Within each biome, Darwin would find different species that were suited to live there

4. Darwin at the Galapagos Noticed that several organisms had differences depending on where they lived

5. Darwin’s Finches Uses beak to crush seeds Uses twigs to probes insects in trees Probes in holds in trees for insects Uses beak to grasp insects

6. Darwin’s Observations Organisms tend to over produce Variation exists within a population

7. Darwin’s Conclusion Darwin summarized his conclusions in The Origin of Species – Common Descent with Modification – Evolution by Natural Selection

8. Back to the giraffe Ancestors of giraffes had slight variations The ones with slightly longer necks survived longer and reproduced more The ones with shorter necks eventually died out

9. Artificial Selection

10. Evidence The fossil record

11. Evidence Biogeography

12. Evidence Homologous body structures Vestigial organs

13. Evidence Embryology

14. Molecular Homologies

15. Theory of the origin of life

16. Early Earth Earth is about 4.6 billion years old Lots of lightning Early atmosphere was full of poisonous gases, water vapor, and no oxygen

17. Habitable Earth About 3.8 billion years ago, Earth cooled enough for water to remain liquid

18. Theory of the origin of life Miller & Urey (1950s) Simulated early Earth’s atmosphere Added a spark of electricity to simulate lightning They made… AMINO ACIDS!

19. 4 Step process for the origin of life

20. The First Eukaryotes About 2 million years ago, eukaryotes evolved (endosymbiosis)