1. Section 4 Adaptation and Survival
Objectives
Identify three kinds of adaptations that help organisms survive.
Describe the four parts of natural selection.
Explain Explain how variation occurs within a population.

2. Section 4 Adaptation and Survival
Objectives, continued
Explain why genetic variation within a population is important.
Explain how resistance to insecticide is a survival characteristic.

3. Adaptations for Obtaining Food
Section 4 Adaptation and Survival
Adaptations for Obtaining Food
An adaptation is a characteristic that improves an individual’s ability to survive and reproduce in a particular environment.
Almost all organisms have adaptations to help them obtain food.

4. Predator-Prey Adaptations
Section 4 Adaptation and Survival
Predator-Prey Adaptations
Many organisms also have adaptations that serve as a defense against predators.
One common adaptation that helps predators and prey is called camouflage. An organism that is camouflaged is disguised so that it is hard to see even when the organism is in view.

5. Adaptations to Interactions
Section 4 Adaptation and Survival
Adaptations to Interactions
Two species can also acquire adaptations because of their interaction with one another.
Adaptations because of interactions can take place between any organisms that live close together.

6. Section 4 Adaptation and Survival
Natural Selection
Inherited characteristics in populations can change over time.
Natural selection is the process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well-adapted individuals do.

7. Natural Selection, continued
Section 4 Adaptation and Survival
Natural Selection, continued
The theory of natural selection explains how a population changes in response to its environment.
If natural selection is always taking place, a population will tend to be well adapted to its environment.
The individuals that are likely to survive and reproduce are those that are best adapted at the time.

8. Natural Selection, continued
Section 4 Adaptation and Survival
Natural Selection, continued

9. Changes in Genetic Variation
Section 4 Adaptation and Survival
Changes in Genetic Variation
In order for natural selection to continue, individuals within the population must be different.
Over time, the population will be made up of more individuals with characteristics that help them survive.
If a population decreases rapidly, a genetic bottleneck occurs. Many characteristics may be lost entirely from a population because all of the individuals with those characteristics died.

10. Section 4 Adaptation and Survival

11. Insecticide Resistance
Section 4 Adaptation and Survival
Insecticide Resistance
Insecticide resistance is also a result of natural selection.
Some individual insects within a population are resistant to certain insecticides. Resistance is an adaptation.
These insects survive and reproduce. They pass the insecticide-resistance genes to their offspring.

12. Adapting to the Environment
Concept Mapping
Use the terms below to complete the concept map on the next slide.
asexual reproduction budding
external fertilization fragmentation
reproduction internal fertilization
sexual reproduction

13. Adapting to the Environment

14. Adapting to the Environment