Deck 11: The Ecology and Evolution of Spiral Distribution

Question 1

"The movement between the natal area or social group and the area or social group where breeding first takes place" (Clobert et al. 2001) describes

A) breeding dispersal.
B) habitat selection.
C) natal dispersal.
D) natal philopatry.

Answer 1

natal dispersal.

Question 2

Animals that practice natal philopatry

A) are born in one place and then move to another location, where they breed, and then return to their birthplace.
B) are born in one place and then move to another location, where they breed, never to return to their birthplace.
C) are born in one place where they breed, and then move to another location.
D) are born in one place where they then remain, sharing the home range or territory with their parents.

Answer 2

are born in one place where they then remain, sharing the home range or territory with their parents.

Question 3

Natal dispersal refers to

A) the movement from the natal area to a new area prior to reproduction.
B) the movement of parents away from their young.
C) the practice of producing offspring spaced a certain number of years apart.
D) the relocation of young offspring to new nest sites.

Answer 3

the movement from the natal area to a new area prior to reproduction.

Question 4

One potential cost of remaining in the birth area is inbreeding, which is costly because it

A) forces the population to maintain some harmful alleles, even though they will probably never be expressed.
B) increases the rate of gene flow between populations.
C) reduces the risk of producing offspring that are homozygous for harmful or lethal recessive alleles.
D) reduces variation among offspring.

Question 5

It is difficult to measure the fitness costs of inbreeding because the frequency of inbreeding is usually low. However, Brown and Brown (1998), during a long-term study of the Mexican jay (Aphelocoma ultramarina), found that

A) fewer of the inbred nestlings survived to the next year when compared with outbred nestlings.
B) inbred pairs appeared to experience a higher rate of hatching failure.
C) the brood sizes of inbred pairs were smaller than those of outbred pairs.
D) all of the above.

Question 6

Reproductive suppression, through either chemical means, such as pheromones, or behavioral means, such as aggression, is a potential cost associated with

A) breeding dispersal.
B) habitat selection.
C) natal dispersal.
D) natal philopatry.

Question 7

Populations of animals can become adapted to local conditions. This situation could provide a potential benefit associated with

A) breeding dispersal.
B) habitat selection.
C) natal dispersal.
D) natal philopatry.

Question 8

Efficiency in finding food and escaping predators, and relatively low levels of aggression and stress associated with social interaction are benefits likely to be associated

A) breeding dispersal.
B) habitat selection.
C) natal dispersal.
D) natal philopatry.

Question 9

Animals that practice natal dispersal may

A) avoid competition with kin for critical resources.
B) face high energy costs.
C) face increased predation risk.
D) all of the above.

Question 10

There has been considerable debate over the role of inbreeding in natal dispersal. Rather than dispersing explicitly to avoid breeding with relatives, some have argued that natal dispersal is more likely the result of

A) competition for habitat sites.
B) deteriorating food supplies.
C) female mate choice.
D) intense competition among males for mates.

Question 11

Höner and colleagues (2007) studied eight clans of spotted hyenas in northern Tanzania between 1996 and 2006, testing four hypotheses for natal dispersal by male hyenas. The hypotheses were that males disperse (1) to avoid competition with other males for mates, (2) to avoid inbreeding, (3) to avoid competition for food, or (4) in response to female patterns of mate choice. Which of the following variables would provide the most direct test of hypothesis 1?

A) the number of main prey animals per adult or yearling hyena
B) the number of reproductively active natal and immigrant males present
C) the number of unrelated adult females in the clan
D) the number of young females available most likely to breed with males

Question 12

Höner and colleagues (2007) studied eight clans of spotted hyenas in northern Tanzania between 1996 and 2006, testing four hypotheses for natal dispersal by male hyenas. The hypotheses were that males disperse (1) to avoid competition with other males for mates, (2) to avoid inbreeding, (3) to avoid competition for food, or (4) in response to female patterns of mate choice. What did their findings suggest was the basis for an immigrating male's selection of clan?

A) the number of main prey animals per adult or yearling hyena
B) the number of reproductively active natal and immigrant males present
C) the number of unrelated adult females in the clan
D) the number of young females available most likely to breed with males

Question 13

Which of the following is the best example of an ultimate cause of natal dispersal, as opposed to a proximate cause?

A) aggression from other group members
B) attainment of appropriate body size
C) avoidance of inbreeding
D) shortage of food at the natal site

Question 14

Which gender in birds is most likely to exhibit natal dispersal?

A) female
B) male
C) There is no gender difference.
D) Natal dispersal does not occur in birds.

Question 15

Which gender in mammals is most likely to show natal dispersal?

A) female
B) male
C) There is no gender difference.
D) Natal dispersal does not occur in mammals.

Question 16

A resource-defense mating system is frequently associated with

A) females being philopatric.
B) male-biased dispersal.
C) male philopatry.
D) no sex bias in dispersal.

Question 17

The fact that female mammals often live in matrilineal social groups in which the benefits of living with kin may be quite high is often associated with

A) a resource-defense mating system.
B) female philopatry.
C) female-biased dispersal.
D) increases in inbreeding.

Question 18

One idea to explain the direction of the sex bias in natal dispersal is that the sex that gets first choice of breeding sites is the one that remains in the natal area; the other sex disperses. Particularly in mammals, what factor is it that seems to determine which sex "gets first choice"?

A) whether females are tolerant of other females' offspring.
B) whether males are involved in early parental care.
C) whether the father will be present when his daughters are old enough to breed.
D) whether the mother will be present when her daughters are old enough to breed.

Question 19

A prediction that arises from the kin cooperation hypothesis is that the magnitude of sex-biased dispersal should increase with increases in social complexity. Devillard and colleagues (2004) tested that hypothesis by reviewing the literature on 11 species of ground-dwelling sciurids (e.g., ground squirrels, marmots, prairie dogs). What characteristic of sciurids made them a particularly appropriate group for this study?

A) Their social structures range from solitary to large social groups comprised of individuals from several generations.
B) They display unusually high frequencies of female-biased natal dispersal.
C) They experience very little feeding competition.
D) They tend to practice resource-defense mating strategies.

Question 20

The process of habitat selection can be divided into three phases: (1) search, (2) settlement, and (3) residency. Typically the ratio of costs to benefits differs across the phases. Which of the following pairings MOST accurately represents the nature of the phase(s)?

A) residency; costly
B) residency and search; beneficial
C) search and settlement; costly
D) search; beneficial

Question 21

The "Allee Effect" is one suggestion dealing with the way that fitness might be related to the presence or absence of conspecifics in a prospective home. Which of the following statements best summarizes the Allee Effect?

A) Individual fitness increases with number of conspecifics at low to moderate densities, then declines from moderate to high densities.
B) Individual fitness will decline as the number of conspecifics in a patch increases.
C) Physical characteristics that correlate with the presence of prey, such as level of light intensity or amount of leaf litter, permit a rapid evaluation of habitat quality.
D) The simple presence of conspecifics serves as a source of indirect information about habitat quality.

Question 22

The presence of heterospecifics in a particular habitat could have both costs and benefits for an animal considering whether to settle there. When Forsman and colleagues (2002) tested that idea by examining whether the presence of resident titmice influenced the settlement and fitness of migrant pied flycatchers, they found that

A) brood sizes of flycatchers were smaller in patches where numbers of titmice had been experimentally increased than in patches from which titmice had been removed.
B) flycatchers breeding closer to titmice had smaller nestlings than those breeding farther away.
C) flycatchers preferred nest boxes placed near an active titmouse nest to those located further away.
D) flycatchers tended to arrive later on forest patches where titmice numbers were increased than on patches where titmice had been removed.

Question 23

There are two general search strategies used by animals during habitat selection: a comparison search or a sequential search. A sequential search is

A) often described as a best-of-N strategy.
B) one in which an animal decides either to accept or reject a location at the time it is visited.
C) one in which an animal revisits some locations.
D) all of the above.

Question 24

The general phenomenon whereby an animal's experience in its natal habitat induces a preference for a post-dispersal habitat with similar qualities is called natal habitat preference induction (NHPI; Davis and Stamps 2004). It has been suggested that NHPI

A) assists in identifying a habitat of sufficient quality in which to settle.
B) increases fitness because the individual's particular phenotype has been shaped by a similar habitat.
C) minimizes the costs of the search phase of habitat selection.
D) all of the above.

Question 25

Conservation efforts using translocation and captive-release techniques

A) are frequently associated with high mortality rates.
B) have been extremely successful.
C) have resulted in most animals demonstrating a reluctance to leave the release site.
D) produces individuals in better condition with increased reproduction rates.

Question 26

Modifications have been proposed to translocation and captive-release programs that might help animals find the release site an acceptable place to settle. These include

A) adding distinctive stimuli and cues characteristic of the release site to the environment in which an animal is being raised.
B) not tranquilizing the animals during transport, so that they are more aware of the fact that they are undergoing a transition.
C) removing all predators from the release site until the subjects have settled.
D) transporting in two stages, so that the first group of settled animals can serve as models for the next group.

Question 27

Situations in which the cues used by animals to select a habitat, e.g., availability of nest sites or prey, actually result in a marked reduction in fitness

A) are more likely to be of natural than of human origin.
B) are referred to as ecological traps.
C) can be easily corrected, once they have been accurately identified.
D) all of the above.

Question 28

Migration is different from natal dispersal because, particularly in long-lived species, migratory species _____ return to their site of origin.

A) almost never
B) do
C) do not
D) rarely

Question 29

A form of migration in which the migratory patterns of individuals within a population differ by age class or gender is called

A) differential migration.
B) facultative migration.
C) obligate migration.
D) one-way migration.

Question 30

If there are sex or age differences within a species in patterns of migratory behavior, the class(es) most likely to migrate are

A) females and juveniles.
B) males.
C) males and juveniles.
D) the ones best able to compete for food on the breeding grounds.

Question 31

Which of the following would NOT be considered a cost of migration?

A) energy costs.
B) increased numbers of young to feed.
C) risk of predation.
D) unstable weather.

Question 32

Reducing the risk of starvation during migration is accomplished by

A) alternating periods of movement and stopover.
B) storing fat before the journey begins.
C) using a fly-and-forage strategy.
D) all of the above.

Question 33

Which of the following is a key characteristic of the Monarch butterflies' Mexican roost sites?

A) Prevailing winds are typically from the south.
B) They are situated along the ocean coast.
C) They occur at elevations lower than 1000 meters.
D) While cool, temperatures usually do not get much below freezing.

Question 34

If a migratory species has endured great hardship to arrive at warmer winter habitats, why do they ever leave to return to summer homes? Because farther from the equator

A) brood sizes are typically smaller, reducing overall energy costs.
B) shorter periods of daylight make the work of brood rearing less stressful.
C) the sought after areas provide protection from predators less critical at other times of the year.
D) all of the above