1. Natural Selection

2. … “the process by which forms of life having traits that better enable them to adapt to specific environmental pressures, predators, changes in climate, or competition for food or mates, will tend to survive and reproduce in greater numbers than others of their kind, thus ensuring the continuation of those favorable traits in succeeding generations.”

3. Natural Selection  Organisms with traits best suited to their environment are more likely to survive and reproduce.

4. TRAIT vs. FEATURE
Feature  Any general structure, characteristic, or behavior of an organism. Ex’s – wings, fur, pattern, color, and migration.
Trait  The specific expression of a feature in an individual. Ex’s – wing length, density of fur, number of spots, intensity of the color, timing of migration.
Variation Several traits for the same feature in a population. Ex – walking stick population exhibited color variation ranging from green to brown.

6. CHARLES DARWIN THEORY
Observed 13 species of Finches on the Galapagos Islands in the 1800’s.
The birds were very similar, except for beak shape
Darwin figured the birds must have had to compete for food. Finches with beak shapes that allowed them to eat available food survived longer and reproduced more offspring than finches without those beak shapes.
After many generations, these groups of finches became separate species.

8. Natural Selection is NOT Random!
Variation (differences) that occurs in a population because of MUTATION is random.
A mutation causes a structural or behavioral adaptation to the species that could benefit, harm, or make no change to the organism.
The success of an adaptation caused from a mutation is NOT RANDOM. Only mutations that benefit an organism living in its environment will be successful.
Differences that help survival and reproduction are much more likely to become common in a population than differences that don’t.

9. List 4 possible reasons or “traits” that suggest
why some candies were eaten (didn’t survive)
List 4 possible reasons or “traits” that suggest why some candies were NOT eaten (DID survive)
How is this similar to natural selection in a real environment?
What real-life issues or situations could contribute to the decline in one population and the success of another?