Question 1

Bright coloration in birds makes them stand out to predators. In female birds that sit on the nest, bright coloration is rare. This is likely the result of

Accepted Answer

A)  coevolution. 
B)  natural selection. 
C)  artificial mutations. 
D)  gene flow. 
E)  stabilizing selection.

Question 2

Evolution can be defined as change in in a population.

Accepted Answer

The answer of Evolution can be defined as change in...

Question 3

Which of the following is an example of assortative mating?

Accepted Answer

A)  A female sparrow chooses a mate because he attracts her by singing a different species' song. 
B)  A female mouse chooses a mate because he is the same color that she is. 
C)  A female sheep chooses a mate because he has previously mated with many females. 
D)  A female lizard chooses to mate with the first male she encounters. 
E)  A dominant male elephant mates with most females in a group, excluding other males from mating with the females.

Question 4

Which trait is the best example of an adaptation?

Accepted Answer

A)  A mutation resulting in weak branches in a species of tree that lives in windy regions 
B)  A mutation resulting in a heat- resistant enzyme in a bacterium living in a hot spring 
C)  A longer tongue in an insect- eating mammal that feeds on insects that live in shallow burrows 
D)  A new mutation that confers Tay- Sachs disease in humans 
E)  A shorter neck in a giraffe that lives in an area with many rival males and tall trees

Question 5

A young male baboon leaves the troop that he was born in and joins a small neighboring troop of small baboons. He quickly rises to become a dominant male. From an evolutionary point of view, what important process has occurred?

Accepted Answer

A)  Genetic drift 
B)  Nonrandom mating 
C)  Natural selection 
D)  Gene flow 
E)  The bottleneck effect

Question 6

Imagine that two men and two women settle on an uninhabited island, no new settlers arrive, and nobody leaves the island for many generations. All four of the settlers have brown eyes, but one of the men carries a recessive gene for blue eyes. Eye color has no effect on fitness. If the percentage of blue- eyed individuals on the island increases from 0% to 25%, what is the probable cause?

Accepted Answer

A)  Genetic drift 
B)  Random mutation 
C)  Natural selection 
D)  Artificial selection

Question 7

How does the founder effect influence the frequency of alleles in a population?

Accepted Answer

The answer of How does the founder effect influence the...

Question 8

In a certain species of salmon, some adult males are extremely large whereas other adult males are very small, compared to the females. There are no intermediate- sized adult males in the population. This is probably the result of

Accepted Answer

A)  stabilizing selection. 
B)  artificial selection. 
C)  directional selection. 
D)  disruptive selection.

Question 9

When a species lives in a constant environment for a long time, the "average type" of individual may have the best chance of surviving and producing the most offspring. What type of selection is occurring?

Accepted Answer

A)  Stabilizing 
B)  Directional 
C)  Sexual 
D)  Artificial 
E)  Disruptive

Question 10

Which of the following phenomena favors individuals with average phenotypes over those with extreme phenotypes?

Accepted Answer

A)  Gene flow 
B)  Genetic drift 
C)  Sexual selection 
D)  Stabilizing selection 
E)  Coevolution

Question 11

According to the Hardy- Weinberg principle, if 75% of the alleles in the gene pool are A1 and 25% are A2, what is the proportion of individuals with genotype A1A2 in this population?

Accepted Answer

A)  0.1875 
B)  0.025 
C)  0.0625 
D)  0.375 
E)  0.5625

Question 12

Based on the information shown in the figure, what do you predict the fourth generation will look like?

Accepted Answer

A)  There is no way to predict what the fourth generation will look like. 
B)  All the hamsters will be tan. 
C)  Five hamsters will be black. 
D)  All the hamsters will have mottled tan/black fur. 
E)  All the hamsters will be black.

Question 13

The gene pool for a particular population is made up of

Accepted Answer

A)  the sum of all the heterozygous individuals in the population. 
B)  all the genes for a certain trait that occur in the population. 
C)  all the alleles for a certain trait in a given individual. 
D)  the sum of all the homozygous individuals in the population. 
E)  all the genes that occur in the population.

Question 14

A bacterial allele that provides resistance to the antibiotic streptomycin is

Accepted Answer

A)  always beneficial to the bacterial cell. 
B)  beneficial to the cell in the presence of streptomycin. 
C)  neither beneficial nor detrimental to the cell. 
D)  always detrimental to the cell. 
E)  beneficial to the cell in the presence of any antibiotic.

Question 15

Individuals who have one dominant allele and one recessive allele for a trait are referred to as .

Accepted Answer

The answer of Individuals who have one dominant allele and...

Question 16

The male peacock's beautiful tail is really a trade- off between

Accepted Answer

A)  artificial selection and natural selection. 
B)  sexual selection and natural selection. 
C)  disruptive selection and natural selection. 
D)  natural selection and genetic drift.

Question 17

Despite causing a life- threatening disease, the sickle- cell allele in some areas of Africa has remained in high frequency in those populations because it protects against malaria. In the United States, malaria was eradicated shortly before World War II by eliminating the mosquito that spreads the disease. What is likely to happen to the frequency of the sickle- cell allele in African Americans living in the United States?

Accepted Answer

A)  The frequency of the sickle- cell allele will not change. 
B)  The frequency of the sickle- cell allele will decrease. 
C)  The normal allele will disappear from the African American population. 
D)  The frequency of the sickle- cell allele will increase. 
E)  The sickle- cell allele will disappear from the African American population.

Question 18

In the population shown in the figure, what is the most common fur color allele in this population?

Accepted Answer

The answer of In the population shown in the figure,...

Question 19

Which of the following can be measured to estimate an organism's evolutionary fitness?

Accepted Answer

A)  The number of eggs it produces over its lifetime 
B)  The size of its offspring 
C)  The number of gametes it produces over its lifetime 
D)  The number of offspring it produces over its lifetime that survive to breed 
E)  The number of offspring it produces over its lifetime

Question 20

Evolution occurs in .

Accepted Answer

The answer of Evolution occurs in ....

Exam 16: How Populations Evolve