3.2 Other Mechanisms of Evolution

What is the result of natural selection in a population?

• A) Sudden change in the allele frequency

• B) Gradual change in the allele frequency

• C) No change in the allele frequency

• D) Decrease in the allele frequency

What is required for new versions of traits to appear?

• A change in the DNA

• A change in the environment

• A change in the diet

• A change in the behavior

What are mutations?

• Predictable changes in DNA

• Random changes in DNA

• Changes in behavior

• Changes in diet

What can mutations potentially lead to?

• New adaptations that increase the fitness of an individual

• Decrease in the fitness of an individual

• No effect on the individual

• All of the above

What is the typical effect of mutations on the reproductive success of an organism?

• Mutations almost always cause early death or lower reproductive success.

• Mutations always increase reproductive success.

• Mutations have no effect on reproductive success.

• Mutations always result in beneficial traits.

Why can't humans just grow gills if the world were suddenly to flood?

• Because humans can adapt quickly.

• Because the trait must already exist somewhere in the population.

• Because humans can only grow lungs.

• Because mutations are goal oriented.

What is Genetic Drift?

• A change in the allele frequency of a population due to natural selection.

• A change in the allele frequency of a population as a result of chance events.

• A change in the allele frequency of a population due to mutation.

• A change in the allele frequency of a population due to migration.

What can cause a shift in allele frequency without an obvious cause?

• Natural selection

• Genetic mutation

• Genetic drift

• Gene flow

What does genetic drift not influence?

• Reproductive success

• Allele frequency

• Population size

• Genetic variation

What is the consequence of genetic drift in a population?

• The population experiences evolution.

• The population remains genetically stable.

• The population increases in size.

• The population becomes extinct.