CFA Natural Selection - 2/22/22 (Eval)

Why is the mouse population changing over time?

• The light mice can reproduce more successfully than the dark mice
• The hawks eat more dark mice than light mice because the dark mice taste better
• The hawks eat more light mice than dark mice because they can see the light mice more easily
• The hawks eat more dark mice than light mice because they can see the dark mice more easily

Definition: natural selection

• inherited characteristic that increases chances of survival
• organisms with traits well suited to their environment survive and reproduce at a greater rate
• a growing population causes a scarcity of resources
• differences in the DNA sequence

Definition: adaptation

• inherited characteristic that increases chances of survival
• organisms with traits well suited to their environment survive and reproduce at a greater rate
• a growing population causes a scarcity of resources
• differences in the DNA sequence

Definition: fitness

• ability to survive and reproduce in a specific environment
• organisms with traits well suited to their environment survive and reproduce at a greater rate
• a growing population causes a scarcity of resources
• differences in the DNA sequence

Over time, the climate of an island became drier, which resulted in changes to the populations of various island finch species. Finch populations with a certain beak shape thrived, while those not having that beak shape decreased. Which of the following describes a necessary condition for these changes in the finch populations to occur?

• fewer mutations
• limited food resources
• limited beak variations
• overproduction of offspring

Which of these would have the least effect on natural selection in a subspecies of giraffes that is geographically isolated from other subspecies of giraffes?

• available niches
• existing predators
• chromosome number
• available food resources

Mutations within a DNA sequence are

• natural processes that produce genetic diversity
• natural processes that always affect the phenotype
• unnatural processes that always affect the phenotype
• unnatural processes that are harmful to genetic diversity

Each of the following is a condition necessary for natural selection to occur EXCEPT 

• more offspring are born than can survive.
•  population size is very large. 
• fitness varies among individuals.
• there is heritable variation among members of the population.

Happens only in small populations, and is the change in the frequency of a gene variant (allele) in a population due to random sampling of organisms.

• Extinction
• Genetic Drift
• Bottleneck Effect
• Founder Effect

This mechanism of evolution occurs when populations migrate.

• Extinction
• Gene flow
• Genetic drift
• Natural Selection