1. Summary of Evolution by Natural Selection. ..

9. Summary of Evolution by Natural Selection
Populations produce more offspring than the environment can support.

17. Summary of Evolution by Natural Selection
Populations over produce offspring.
There is genetic variation in the population.
What are the sources of variation in a population?

26. Summary of Evolution by Natural Selection
Populations over produce offspring.
There is variation in the population.
There is a “selective pressure” that causes a struggle for existence. Examples:
limited food, water, territory, mates.
change in environment
predators

34. Summary of Evolution by Natural Selection
Populations over produce offspring.
There is variation in the population.
There is a “selective pressure” that causes a struggle for existence.
Differential survival and reproduction: The individuals with the most favorable variation will be most likely to survive and reproduce to pass on their genes
“adaptation”

39. Summary of Evolution by Natural Selection
Populations over produce offspring.
There is variation in the population.
There is a “selective pressure” that causes a struggle for existence.
Differential survival and reproduction: The individuals with the most favorable variation will be most likely to survive and pass their genes
Over generations, favorable variations increase: Each new generation will contain more offspring from individuals with the favorable variation than those with unfavorable ones, changing the population over time.
“adaptation”

40. Pocket Mouse (10 minutes)
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Illustrate notes using this example

41. Summarize the five “steps” of evolution by natural selection by explaining one of these examples: