1. Do you think these birds are related? Why or Why Not? A B C D E What do you think each bird eats? Why do you think that?

2. Change Over Time Organisms adapt to suit their environment – they evolve

3. Who is Darwin? Charles Darwin is considered the father of modern evolutionary theory Charles Darwin is considered the father of modern evolutionary theory Darwin’s 5 year voyage as the naturalist on the HMS Beagle helped him develop the theory of how change over time occurs Darwin’s 5 year voyage as the naturalist on the HMS Beagle helped him develop the theory of how change over time occurs

4. Section 15-1 Figure 15–1 Darwin’s Voyage

5. They explored South America and the South Pacific, including the now famous Galapagos Islands off the coast of South America They explored South America and the South Pacific, including the now famous Galapagos Islands off the coast of South America They collected samples of fossils and live specimens for study They collected samples of fossils and live specimens for study The islands had animals that were unique, but they also had species that were similar to those on the mainland The islands had animals that were unique, but they also had species that were similar to those on the mainland –Ex: marine iguanas and tortises

6. Pinta Island Intermediate shell Pinta Isabela Island Dome-shaped shell Hood Island Saddle-backed shell Hood Floreana Santa Fe Santa Cruz James Marchena Fernandina Isabela Tower Giant Tortoises of the Galápagos Islands Section 15-1

7. Darwin Presents His Case Through his observations abroad, he concluded that natural variations or differences occur among individuals of a population Through his observations abroad, he concluded that natural variations or differences occur among individuals of a population –EX: Galapagos Finches

9. Natural Selection What is Natural Selection: What is Natural Selection: –Organisms with more favorable traits or variations tend to survive and reproduce; organisms with less favorable traits are less likely to survive

10. 2 Main Points of Natural Selection 1. Struggle for existence: competition for territory, food, water, and mates 2. Survival of the fittest: some organisms are better suited to survive in an environment as a result of adaptations

11. - Examples of Adaptations Mimicry: copying the appearance of other species Mimicry: copying the appearance of other species Camouflage: blending into the environment Camouflage: blending into the environment Adaptations can take millions to hundreds of years Adaptations can take millions to hundreds of years Bacteria show adaptations in 50 or less years Bacteria show adaptations in 50 or less years

12. Mimicry

13. Camouflage

14. Before the Industrial Revolution, the white peppered moths were camouflaged better than the black peppered moth in England.

15. However, the pollution caused by the industrial revolution caused a lot of the trees around England to become a black color. The number of white moths decreased, where the number of black moths increased, this is population change over time

16. Evidence for Change Over Time 1. Fossils: by using fossils, scientists can show the sequence of evolution in an organism 2. Geography: organisms that are similar but live in different parts of the world –Earth has changed over the last 4.6 billion years: Pangaea (the super continent)

18. Beaver NORTH AMERICA Muskrat Capybara SOUTH AMERICA Coypu Figure 15–14Geographic Distribution of Living Species Section 15-3 Beaver Muskrat Beaver and Muskrat Coypu Capybara Coypu and Capybara

19. Evidence for Evolution 3. Homologous Structures: structures that are similar and seen in different species Ex: forelimbs of humans/batsEx: forelimbs of humans/bats

20. Evidence for Evolution 4. Vestigial Structures: a body structure that appears to no longer have a function Ex: appendix in humans, hipbones in snakesEx: appendix in humans, hipbones in snakes

21. Vestigial Structures

22. Evidence for Evolution 5. Embryology: by studying unborn organisms, we can see structures in common during development in different organisms

23. Embryology

24. Embryology

25. Embryology

26. 6. Genetic Relationships: DNA comparisons help establish evolutionary relationships between different species

27. Extra Tidbit of Info Sometimes organisms with close relationships (like symbiosis) evolve together in response to each other’s changes Madagascar orchid and hawk mothMadagascar orchid and hawk moth

28. To reach the nectar of this orchid requires a 30 centimeter (eleven inch) proboscis (tongue) to penetrate the long nectar spur (white arrow).