AP - Unit 7

Darwin observed that most organisms produce

• more offspring than will survive to adulthood

• only 1 offspring

• only a few offspring

• only as many offspring as they can care for

Choosing a trait we like and breeding for it is called

• artificial selection

• natural selection

• evolution

Natural selection acts on

• individuals

• populations

Natural selection acts on

• phenotypes

• genotypes

Differences observed between males and females of the same species is the result of

• sexual selection

• natural selection

A strong wind, blowing pollen further than normal is an example of

• bottleneck effect

• mutations

• founder effect

• gene flow

Occurs when one extreme phenotype is selected.

Example: Individuals may be tall, med, or short

Only the short ones survive

• Directional selection

• Stabilizing selection

• Disruptive selection

Selection against BOTH extreme phenotypes

Example: Individuals can be tall, med, or short

Only the medium ones survive

• Directional selection

• Disruptive selection

• Stabilizing selection

Selection FOR both extreme phenotypes

Example: Individuals can be tall, med, or short

Only the tall and short survive. The mediums die out

• Directional selection

• Disruptive selection

• Stabilizing selection

A natural event that separates a population, usually decreasing its diversity represents the

• bottleneck effect

• founder effect

• natural selection

• gene flow