1. 15.3 Darwin Presents his Case
Darwin struggled with his findings
25 years later after getting essay from Alfred Wallace…On the Origin of Species

2. Artificial selection-nature provides variation, humans select varieties they find useful

3. Struggle for existence-competition for food, living space
Fitness: the ability of an individual to survive and reproduce in its environment
Adaptation: any inherited characteristic that increases an organism’s chance of survival

4. Survival of the fittest
= natural selection
Descent with modification-the principle that each living species has descended, with changes, from other species over time

5. Evidence for Evolution
The Fossil Record-Layers of rock show change
Geographic Distribution of Living Things
Homologous Body Structures
Similarities in Early Development

7. Homologous Structures
Have different mature forms
Develop from the same embryonic tissues
Provide evidence that 4-limbed vertebrates descended with modifications from common ancestors

10. Vestiges (traces) of homologous organs in other species
Vestigial Organs
Organs reduced in size
Vestiges (traces) of homologous organs in other species
Appendix in humans

12. Similarities in Embryology