Deck 10: Mating Systems

Question 1

Kirk's dik-dik is a small African antelope that usually forms male-female pairs. It is possible that monogamy evolved in this species because males are required to protect offspring from other rival males. This would be an example of the

A) mate limitation hypothesis.
B) mate guarding hypothesis.
C) mate assistance hypothesis.
D) infanticide hypothesis.

Answer 1

D

Question 2

Kirk's dik-dik is a small African antelope that usually forms male-female pairs. Males place their scent marks over those of the female, which hides the signals of sexual receptivity that females produce when they are fertile. This finding supports the

A) mate limitation hypothesis.
B) mate guarding hypothesis.
C) mate assistance hypothesis.
D) infanticide hypothesis.

Answer 2

B

Question 3

Kirk's dik-dik is a small African antelope that usually forms male-female pairs. If males are experimentally removed from pairs, females wander from their territories into the territories of other males. This finding supports the

A) mate limitation hypothesis.
B) mate guarding hypothesis.
C) mate assistance hypothesis.
D) infanticide hypothesis.

Answer 3

B

Question 4

Kirk's dik-dik is a small African antelope that usually forms male-female pairs. If males are experimentally removed from pairs, the number of offspring reared by the single female falls sharply due to her inability to provide enough resources. This finding supports the

A) mate limitation hypothesis.
B) mate guarding hypothesis.
C) mate assistance hypothesis.
D) infanticide hypothesis.

Question 5

Genetic monogamy is

A) extremely rare.
B) the rule (with a few exceptions) among mammals, but not among birds.
C) the rule (with a few exceptions) among birds, but not among mammals.
D) never found in reptiles.

Question 6

According to the socio-ecological framework, monogamy should evolve when

A) resources in the environment are clumped and easily defensible.
B) there is a low cost to search for and find individual mates.
C) neither sex can monopolize access to mates or resources.
D) resources are evenly distributed but females occur in groups.

Question 7

According to the socio-ecological framework, resource defense polygyny should evolve when

A) resources in the environment are clumped and easily defensible.
B) there is a low cost to search for and find individual mates.
C) neither sex can monopolize access to mates or resources.
D) resources are evenly distributed but females occur in groups.

Question 8

According to the socio-ecological framework, female defense polygyny should evolve when

A) resources in the environment are clumped and easily defensible.
B) there is a low cost to search for and find individual mates.
C) neither sex can monopolize access to mates or resources.
D) resources are evenly distributed but females occur in groups.

Question 9

Refer to the figure.
Based on these results, this species most likely exhibits

A) polygynandry/promiscuity.
B) polyandry.
C) monogamy.
D) polygyny.

Question 10

Male great tinamous guard a nest into which a female lays an egg from their mating. The next day she mates with a different male; the first male also mates with a different female, which places her egg in his nest. This species exhibits

A) polygynandry/promiscuity.
B) polyandry.
C) monogamy.
D) polygyny.

Question 11

If you study a pair of European beavers, you will find that all of the young in their colony are genetic offspring of the pair. This species exhibits

A) polygynandry/promiscuity.
B) polyandry.
C) monogamy.
D) polygyny.

Question 12

Long-term storage of sperm in some species of tortoise allows a female to produce a clutch of eggs with offspring fathered by multiple males. This species exhibits

A) polygynandry/promiscuity.
B) polyandry.
C) monogamy.
D) polygyny.

Question 13

Red deer males compete to control access to an entire herd of does, meaning that a single male will mate with multiple females, while other males have zero fitness. This species exhibits

A) polygynandry/promiscuity.
B) polyandry.
C) monogamy.
D) polygyny.

Question 14

Refer to the figure.
These results illustrate that in this species,

A) the absence of a male partner does not significantly impact the number of offspring born, but causes a decline in the number of offspring to emerge from the nest.
B) the absence of a male partner causes a significant decline in the number of offspring born and that emerge from the nest.
C) the absence of a male partner significantly impacts the number of offspring born, but not the number that emerge from the nest.
D) the absence of a male partner does not significantly impact survival of offspring.

Question 15

Refer to the figure.
Which hypothesis for monogamy do these results best support?

A) The mate limitation hypothesis.
B) The mate guarding hypothesis.
C) The mate assistance hypothesis.
D) The infanticide hypothesis.

Question 16

Refer to the figure, which shows mean area of comb produced in colonies of a polyandrous bee species. In bees, the comb in the hive is where offspring are reared and food is stored.
These results best support the

A) good genes hypothesis.
B) genetic compatibility hypothesis.
C) genetic diversity hypothesis.
D) inbreeding avoidance hypothesis.

Question 17

Refer to the figure below, which shows the mean area of comb produced in colonies of a polyandrous bee species. In bees, the comb in the hive is where offspring are reared and food is stored.
While some members of the genus Apis are highly polyandrous, most other bee species are not. These results suggest that polyandry evolved in this genus because

A) females receive genetic benefits in terms of improved offspring viability by mating multiply.
B) increased hive diversity increases productivity of the hive because of a varied workforce.
C) increased genetic diversity enhances disease or parasite resistance.
D) by mating multiply, females can avoid inbreeding, which would create less heterozygous offspring.

Question 18

Male plains zebras defend a harem of females that forms to reduce the risk of predation and avoid harassment by bachelor males. This species exhibits

A) female defense polygyny.
B) resource defense polygyny.
C) lek polygyny.
D) scramble competition polygyny.

Question 19

Male Grevy's zebras set up territories near water sources where receptive females are likely to cluster. This species exhibits

A) female defense polygyny.
B) resource defense polygyny.
C) lek polygyny.
D) scramble competition polygyny.

Question 20

Male white-bearded manakins gather in an arena, which contains no resources or practical utility, to display to females on the rainforest floor. This species exhibits

A) female defense polygyny.
B) resource defense polygyny.
C) lek polygyny.
D) scramble competition polygyny.

Question 21

Male thirteen-lined ground squirrels search extensively for females, who are widely distributed and receptive for only a short period during the breeding season. This species exhibits

A) female defense polygyny.
B) resource defense polygyny.
C) lek polygyny.
D) scramble competition polygyny.

Question 22

Give the primary reason that monogamy in male animals would be considered a Darwinian puzzle.

Question 23

Polyandry in females might be advantageous if polyandrous females were to secure some genes from their partners that were especially compatible with the genes in their eggs. State a prediction that follows from this hypothesis.

Question 24

In the dark-eyed junco, the offspring of females and their extra-pair mates are more likely to survive to reproduce, and have higher reproductive success, than the offspring of females and their pair-bonded mate. While this could be explained by the good genes hypothesis, it could also be the result of maternal effects (females invest more in eggs sired by extra-pair mates). Describe how you could test if these offspring differences are due to good genes or maternal effects.

Question 25

In addition to indirect genetic benefits, polyandry can evolve due to direct benefits that females receive. Describe three direct benefits that polyandrous females receive.

Question 26

Polygyny, multiple mating by males, is in fact driven by female behavior as a result of predation pressure or food distribution. Describe two types of polygyny, and explain how female behavior and needs determine this type of mating system.