Question 1

In some species of spider, the male places a copulatory plug into the genital opening of the female after he mates with her. In some cases this plug consists of

Accepted Answer

The answer of In some species of spider, the male...

Question 2

Applying repellant odors or copulatory plugs, mate guarding, and satellite behavior are all examples of

Accepted Answer

These strategies are used by males to compete with other males for access to females, which is a form of intrasexual competition.

Question 3

An increase in the probability of fertilization, an increase in the genetic diversity of offspring, and/or an increase in the accumulation of material benefits, such as nutritional nuptial gifts, are all potential benefits that have been proposed for a

Accepted Answer

These benefits are associated with a female mating with more than one male, a strategy known as polyandry. It can lead to increased genetic diversity among offspring, higher chances of fertilization, and in some cases, females may receive material benefits from multiple mates.

Question 4

A particularly gruesome form of sexual interference is infanticide. Among Hanuman langurs (Presbytis entellus), the primate species in which infanticidal male intruders were first reported, it has been found that the behavior

Accepted Answer

Infanticide among Hanuman langurs is a strategy used by incoming males to bring the females back into estrus sooner, thereby increasing their own chances of siring offspring. By eliminating the infants that are not their own, these males reduce the interbirth interval, allowing them to father the next generation of infants more quickly.

Question 5

Sato and Goshima (2007) studied mate preferences of female stone crabs (Hapalogaster dentata) in aquaria and found that the females use chemical cues rather than visual cues to make their choice between two males. They did this by

Accepted Answer

Sato and Goshima (2007) found that female stone crabs use chemical cues by placing the test males in opaque plastic pipes with very narrow openings, which allowed the passage of chemical cues but not visual cues.

Question 6

Sato and Goshima (2007) studied mate preferences of female stone crabs (Hapalogaster dentata) in aquaria and found that the females use chemical cues rather than visual cues to make their choice between two males. The results indicated that females

Accepted Answer

The answer of Sato and Goshima (2007) studied mate preferences...

Question 7

Which of the following examples of nuptial gifts doesn't provide energy directly to the mating female, but is valuable to her and to her eggs nonetheless?

Accepted Answer

Distasteful tasting alkaloids, while not providing direct energy, can be valuable as they often serve to protect the female and her eggs from predators by making them less palatable.

Question 8

The ability to provide sufficient sperm, to provide resources such as nuptial gifts, to hold a high quality territory, to provide high quality parental care, or to provide good genes are all examples of

Accepted Answer

These are all examples of traits or behaviors that females might consider when choosing a mate, indicating how males can be selected based on their ability to provide resources, care, or genetic benefits to offspring.

Question 9

Takahashi and Kohda (2004) found that female gobies (Rhinogobius brunneus) preferentially choose to mate with males that perform their courtship dance in the fastest water currents. This seems to be related to the fact that males who are unable to court in fast moving water are

Accepted Answer

The answer of Takahashi and Kohda (2004) found that female...

Question 10

Hamilton and Zuk (1982) were the first to propose that the elaborate ornaments of males represent reliable signals of health and nutritional status. They tested this by surveying the literature on avian parasites and determining the risk of infection for each bird species. Specifically, they predicted that in species with a low risk of parasite infection,

Accepted Answer

In species with a low risk of parasite infection, males would not need to be brightly colored to signal health, as the risk of infection is low.

Question 11

Bright coloration, symmetrical body structures or markings, or the elaborateness of a structural display, such as a bower, are indicators that a female might use to judge a male's genetic quality because they

Accepted Answer

These traits are often costly to produce and maintain, indicating that only genetically fit males can afford such displays, making them reliable indicators of genetic quality.

Question 12

Several studies have suggested that some species seem to base their selection of a mate on the makeup of the other individual's major histocompatibility complex (MHC). It appears that a female, for example, will seek an MHC makeup in a potential mate that

Accepted Answer

A different MHC makeup in a potential mate is preferred because it increases the genetic diversity of the offspring, which can enhance their immune system and overall survival chances.

Question 13

Zahavi's handicap principle suggests that females

Accepted Answer

Zahavi's handicap principle posits that certain elaborate traits in males, which may seem to be a disadvantage (like a peacock's tail), actually serve as honest signals of the male's fitness. Females prefer males with these traits because they demonstrate the male's ability to survive despite the handicap, indicating good genes.

Question 14

Petrie (1994) paired each of several peacocks with four peahens, chosen randomly, in a laboratory. The peacocks varied in terms of the number of eye-spots on their trains. All the offspring were raised under common conditions. When the offspring were 84 days old, the offspring of the males with more elaborate trains weighed more than the offspring of those with less elaborate trains. This difference in offspring viability cannot be due to differences in the quality of the females because the

Accepted Answer

The matings were arranged arbitrarily by the experimenter, ensuring that the variation in offspring viability was not influenced by the female selection process but rather could be attributed to the traits of the males.

Question 15

An attempted explanation of the fact that a female's choice often reflects selection for an exaggerated characteristic in a male is called the

Accepted Answer

The runaway selection hypothesis, proposed by Ronald Fisher, explains how female preference for certain male traits can lead to an exaggeration of those traits over generations, as females often choose mates based on these desirable characteristics.

Question 16

When Jones and colleagues (1998) conducted laboratory experiments designed to evaluate the fitness consequences of mate choice for female sandflies (Lutzomyia longipalpis) and their offspring they found no evidence that mating with attractive males influenced the viability of her offspring. They did find that the mating success of sons increased with the attractiveness of the father. These findings support the

Accepted Answer

The findings support the runaway selection hypothesis, which suggests that females prefer traits in males that are not necessarily linked to survival advantages but become exaggerated over time due to female preference, leading to increased mating success of sons with those traits.

Question 17

The finding by Madden and Tanner (2003) that female bowerbirds, when given a choice of grapes of different colors, prefer to eat blue ones, and that male bowerbirds prefer to decorate their bowers with blue objects is consistent with the

Accepted Answer

The sensory bias model suggests that preferences in a mate choice context can evolve if one sex (usually females) has a pre-existing bias for certain sensory stimuli. In the case of the bowerbirds, the females' preference for blue objects, including food, indicates a pre-existing sensory bias towards the color blue. This bias is then exploited by males who decorate their bowers with blue objects to attract females, fitting the sensory bias model.

Question 18

Cryptic female choice refers to a female's

Accepted Answer

Cryptic female choice is a phenomenon where a female can influence the paternity of her offspring after mating by selecting sperm from among those of different males. This can occur through various mechanisms within the female reproductive tract.

Question 19

The term sexual conflict refers to

Accepted Answer

Sexual conflict refers to the evolutionary conflict between the reproductive interests of males and females. This arises because what is evolutionarily advantageous for one sex may not be for the other, leading to different strategies and behaviors to maximize reproductive success.

Quiz 14: Reproductive Behavior