1. Selection

2. Essential Vocab: Species A group of organisms that can reproduce and have fertile offspring.

3. Essential Vocab: Population A group of individuals of the same species that live in the same geographic region.

4. Essential Vocab: Variation A difference in a physical trait. Example 1: Tortoises that live in areas with tall plants have long necks and legs. Example 2: Finches that live in areas with hard-shelled nuts have strong beaks.

5. Essential Vocab: Adaptation A feature that allows an organism to better survive in its environment. Can lead to genetic change in a population. (better adaptations = survive, reproduce, genes passed on) This Antarctic ice fish is adapted to live in cold temperatures by not having red blood cells. This makes the blood thinner and easier to pump through the body in cold temps.

6. More Important Vocab… Fitness: The ability to survive and reproduce. Gene Pool: All genes in a population that interbreeds. Mutation: Change in the DNA. Source of genetic variation.

7. Natural Selection Process in nature that results in survival of the fittest. “Survival of the fittest”: individuals best adapted to the environment will be most likely to survive and reproduce.

8. Principles of Natural Selection More offspring are produced than can survive. Variation must exist within a species. Some variations help individuals survive and reproduce. Over time, variations best adapted to the environment will become more prevalent in the population.

9. Peppered Moths White moths camouflaged on white trees Black moths were not Industrial Revolution deposits black soot on white trees Black moths are now camouflaged now camouflaged

10. Artificial Selection Selective breeding by humans to produce offspring with desirable characteristics. Examples: Dog breeders breed for specific traits. Farmers cross plants to produce more food or different types of food. +=

11. Sexual Selection A form of natural selection involving traits that help an organisms find/attract a mate. Examples: –Antlers (for fighting with other males) –Bright plumage in birds Drawbacks –More visible to predators –Require a lot of energy to maintain