1. Darwin’s Theory of Evolution by Natural Selection
Living things overproduce

2. Darwin’s Theory of Evolution by Natural Selection
There is variation among offspring

3. Darwin’s Theory of Evolution by Natural Selection
There is a struggle to survive

4. Darwin’s Theory of Evolution by Natural Selection
Those that survive are most fit

5. Natural Selection: “Survival of the Fittest”
Fitness = ability to survive and reproduce
Fitness is the result of adaptations – inherited characteristics that increase an organism’s chance of survival

6. Descent with Modification
Over time, natural selection produces organisms with different structures
Today’s species look different from their ancestors
Each species descended with changes over time

7. Descent with Modification
Implies that all living things are related to one another
COMMON ANCESTOR