15-3 Evidence of Charles Darwin

Pg. 378

A. Inherited Variation and Artificial Selection

• 1. Artificial Selection occurs when humans choose the most useful variations provided by nature.

B. Evolution by Natural Selection

• 1. The struggle for existence means that all organisms must compete for food, living space, and other resources.

B. Evolution by Natural Selection

• 2. Fitness is the ability of an individual to survive and reproduce.– ↑ Fitness = ↑ Survival

B. Evolution by Natural Selection

• 3. Adaptations are inherited characteristics that increase an organisms chance of survival.

B. Evolution by Natural Selection• 4. Individuals with the best adaptations +

fitness, have a higher chance of surviving. The process is Survival of the Fittest!

B. Evolution by Natural Selection

• 5. Natural selection occurs when nature causes changes in the inherited characteristics of a population.

B. Evolution by Natural Selection

• 6. Descent with Modification describes the changes over time that change an individuals structures and habitats.

B. Evolution by Natural Selection

• 7. The principle of common descent states that all species-living/extinct- came from a common ancestor.

B. Evolution by Natural Selection

• 8. Homologous Structures develop from similar embryonic tissues but have different mature forms.

B. Evolution by Natural Selection

• 9. Vestigial Organs are traces of homologous structures that serve no purpose.