Deck 53: Community Ecology

Question 1

Snails typically avoid sunlit areas,but some snails infected with certain parasites become attracted to light and prefer sunlit areas.Which of the following is the most likely hypothesis given the life cycles of many parasites?

A)The parasite itself must be exposed to light in order to survive in the snail.
B)The parasite manipulates the behavior of the snail so that it gets eaten more readily,which allows the parasite to complete its life cycle.
C)The snail is behaving differently in order to rid itself of the parasite.
D)The snail is dying from the parasite and is therefore looking for the light.
E)The parasite must exit the snail in a sunlit area in order to move and find its next host.

Answer 1

B

Question 2

People with at least one copy of the HLA-B53 gene are better able to beat back malarial infections before the infection progresses.If this is a coevolutionary arms race between Plasmodium and humans,what would the next step in this race be?

A)to see humans with more than one copy of the HLA-B53 gene
B)to see humans without the HLA-B53 gene
C)to see Plasmodium populations that counter the HLA-B53 gene
D)to see Plasmodium populations that have the HLA-B53 gene

Answer 2

C

Question 3

Figure 53.4
Based on the figure above,what result would you expect if you replaced the crabs with broken mussel shells?

A)the same result as the experiment with crabs
B)no difference in shell thickness
C)a higher degree of difference than the crab experiment
D)impossible to hypothesize

Answer 3

A

Question 4

What is the main difference between asymmetric competition and symmetric competition?

A)One species is outcompeted completely in asymmetric competition.
B)Competition is barely measurable in symmetric competition.
C)The fitness reduction is roughly equal between each species in symmetric competition.
D)None of the above answers applies.

Question 5

The competitive exclusion principle states that

A)it is not possible for two species with the same niche to coexist.
B)it is possible for two species with the same niche to coexist.
C)it is not possible for two species with different niches to coexist.
D)it is possible for two species with different niches to coexist.

Question 6

In the hypothesis that C.stellatus (a species of barnacle)is competitively excluded from the lower intertidal zone by B.balanoides (another species of barnacle),what could be concluded about the two species?

A)The fundamental and realized niches of B.balanoides and C.stellatus are both identical.
B)The fundamental and realized niches of B.balanoides and C.stellatus are both different.
C)The fundamental and realized niches of B.balanoides are different,but the fundamental and realized niches of C.stellatus are identical.
D)The fundamental and realized niches of B.balanoides are identical,but the fundamental and realized niches of C.stellatus are different.

Question 7

Which would be the best way to directly test the hypothesis that C.stellatus (a species of barnacle)is competitively excluded from the lower intertidal zone by B.balanoides (another species of barnacle)?

A)Place individuals of each species in a jar and see which species survives.
B)Remove all B.balanoides from the lower intertidal zone.
C)Transplant B.balanoides to the upper intertidal zone.
D)Clear rocks in an entire area and document recolonization events.
E)Remove all C.stellatus from the upper tidal zone.

Question 8

Figure 53.2
What is the term used to describe the process shown in the panels in the figure above?

A)competition
B)species interaction
C)niche differentiation
D)niche realization

Question 9

Figure 53.1
In looking at the figure above,what conclusions can be drawn?

A)Both species eat all sizes of seeds.
B)Both species compete for seeds of intermediate size.
C)Both species compete for all sizes of seeds.
D)Both species compete for all sizes of seeds other than those of intermediate size.

Question 10

While traveling in Texas,you stumble across a snake with red,yellow,and black bands.You somehow remember that this could be a poisonous coral snake or a harmless milk snake,but you forget how to differentiate them because they both have similar colors and banding patterns.You wisely decide not to pick up the snake.What defense was successful in preventing you from grabbing the snake?

A)constitutive defense
B)Müllerian mimicry
C)Batesian mimicry
D)inducible defenses
E)none of the above

Question 11

Some birds follow moving swarms of army ants in the tropics.As the ants march along the forest floor hunting insects and small vertebrates,birds follow and pick off any insects or small vertebrates that fly or jump out of the way of the ants.What is the specific benefit relationship?

A)Birds benefit from the association,but have no impact on the ants.
B)Birds benefit from the association and harm the ants.
C)Birds and ants benefit from the association.
D)Birds do not benefit from the association,but the ants do.
E)Neither birds nor ants benefit from the association.

Question 12

In biology,a coevolutionary arms race occurs when

A)a country develops a new weapon.
B)a new species evolves into two separate species.
C)a new niche is created.
D)a pair of species influences each others' evolution.

Question 13

Some birds follow moving swarms of army ants in the tropics.As the ants march along the forest floor hunting insects and small vertebrates,birds follow and pick off any insects or small vertebrates that fly or jump out of the way of the ants.This is an example of what kind of species interaction?

A)competition
B)consumption
C)commensalism
D)parasitism
E)mutualism

Question 14

Which hypothesis supports the observation that herbivores do not generally eat all of the available plants?

A)top-down control hypothesis
B)poor nutrition hypothesis
C)plant-defense hypothesis
D)a combination of all of the above
E)none of the above

Question 15

Figure 53.5
In the figure above,which of the following statements is true?

A)All of the species of insects shown are in the order Hymenoptera.
B)There are no true mimics in the insects shown.
C)All of the insects are displaying Batesian mimicry.
D)Half of the insects shown are harmless.

Question 16

Figure 53.4
What conclusion can you draw from the figure above?

A)Without direct contact,mussels can sense the presence of crabs.
B)Mussels can sense the presence of crabs only visually.
C)Mussels are increasing their shell thickness in response to water current.
D)Shell thickness is a non-inducible defense.

Question 17

Which of the following is not a type of consumption?

A)predation
B)mutualism
C)herbivory
D)parasitism

Question 18

Figure 53.5
In the figure above,the labeled groups,which group is displaying Batesian mimicry?

A)group A
B)group B
C)both groups A and B
D)none of the above groups

Question 19

Figure 53.1
According to the figure above,which species is more successful in competing for seeds?

A)species 1
B)species 2
C)These species do not compete for seeds.
D)This figure does not illustrate which species is more successful.

Question 20

Figure 53.3
In the figure above,which species is the stronger competitor?

A)species 1
B)species 2
C)Both species compete equally.
D)It is not possible to tell from this figure.

Question 21

Which of the following is most likely the main advantage of controlled burnings of forested areas?

A)Controlled burnings make up for years of preventing fires.
B)Controlled burnings clear forested areas for farmland.
C)Controlled burnings prevent the overgrowth of the underbrush.
D)Controlled burnings allow new species to form.

Question 22

Which are the only two interaction types to depend on density and effective defense to determine the short-term impact?

A)competition and consumption
B)consumption and parasitism
C)parasitism and mutualism
D)mutualism and commensalism

Question 23

Figure 53.11
According to Figure 53.11,a species has the highest chance of extinction when

A)the island is large and close to the mainland.
B)the island is small and close to the mainland.
C)the island is large and remote.
D)the island is small and remote.

Question 24

A measure of how much a community is affected by a disturbance is termed

A)resilience.
B)resistance.
C)stability.
D)primary productivity.

Question 25

During succession,tall canopies of maple trees form allowing chipmunks to be better hidden against hawks.This is an example of

A)interaction.
B)tolerance.
C)inhibition.
D)facilitation.

Question 26

Which one of the following animals would most likely be defined as a keystone species?

A)sea otter
B)housefly
C)fathead minnow
D)nauplii (a species of zooplankton)

Question 27

Bouchard and Brooks (2004)studied the effect of insect flight on dispersal and speciation in rain-forest insects.They sampled all of the insects in the study area and found that 60 insect species are flightless and 19 are macropterous (able to fly).After analyzing the results of the Bouchard and Brooks study,you conclude that macropterous and flightless insects in the rain forests of northeastern Australia have dispersed and speciated in similar manners.What does this say about flight in these insects?

A)Flight,although used for locomotion,is not increasing the species dispersal efficiency in this community.
B)Flight is not important in these insects for success.
C)Flight is important only for mating.
D)Flight is the only factor involved in speciation in those insects with flight,and thus it is not important for dispersal of these species.
E)Nothing further can be said about flight.

Question 28

Bouchard and Brooks (2004)studied the effect of insect flight on dispersal and speciation in rain-forest insects.They sampled all of the insects in the study area and found that 60 insect species are flightless and 19 are macropterous (able to fly).From this information what can you conclude? (P.Bouchard and D.R.Brooks.2004.Effect of vagility potential on dispersal and speciation in rainforest insects.Journal of Evolutionary Biology 17:994-1006.)

A)Flightless insects have a greater dispersal potential from this study area.
B)Flightless insects are more numerous in the study area.
C)Flightless insects have a higher diversity in the study area.
D)Flightless insects are better suited for the tropics.
E)This data does not lead to a conclusion.

Question 29

Which of the following is not an example of a mutualism?

A)fungi residing in plant roots,such as endomycorrhizae
B)bacteria fixing nitrogen in plants
C)rancher ants that protect aphids in exchange for sugar-rich honeydew
D)birds eating insects jumping out of the path of army ants

Question 30

Figure 53.7
What does the graph in the figure above tell you about the definition of a keystone species?

A)A keystone species has little interaction with other species in an environment.
B)A keystone species removed from a community could have drastic effects.
C)A keystone species can be any species.
D)A keystone species added to a community can make it more robust.

Question 31

Clements's view of biological communities is that of a highly predictable and interrelated structure,while Gleason's view of biological communities is that individual species operate independently.If we set up many identical sterilized ponds in the same area and allowed them to be colonized,what should we predict if Gleason's hypothesis is the one we believe is correct?

A)Identical plankton communities will develop in all ponds.
B)Similar plankton communities will develop in all ponds.
C)Different plankton communities will develop in all ponds.
D)Limited plankton communities will develop in all ponds.

Question 32

Figure 53.8
Clements's view of biological communities is that of a highly predictable and interrelated structure,while Gleason's view of biological communities is that individual species operate independently.Looking at the results in the figure above,which hypothesis (by Clements or Gleason)is supported by the data?

A)Clements
B)Gleason
C)both
D)neither

Question 33

Figure 53.10
In figure above,what can be stated about species diversity and latitude?

A)As latitude increases,diversity decreases.
B)As latitude decreases,diversity decreases.
C)Species diversity is independent of latitude.
D)Species diversity and latitude cannot be compared using this figure.

Question 34

Figure 53.9
In the figure above,which community has the highest species diversity?

A)community 1
B)community 2
C)community 3
D)community 4

Question 35

Figure 53.9
In the figure above,which community has the highest species richness?

A)community 1
B)community 2
C)community 3
D)community 4

Question 36

During a one year study,researchers found no difference in treehopper populations in any of their control and experimental groups.What could they measure during the second year to gain information about why this might have occurred?

A)Measure the number of ant females.
B)Measure the relative sizes of the treehoppers.
C)Measure the relative abundance of jumping spiders.
D)Measure the success of treehoppers with a different ant species.

Question 37

Figure 53.11
Which of the following statements regarding the figure above is true?

A)Immigration rates are higher on smaller islands.
B)Extinction rates are highest on large islands close to the mainland.
C)Species richness should be higher on larger islands close to mainland.
D)Species diversity should be highest on larger islands away from mainland.

Question 38

What is the main difference between a disturbance and a disturbance regime?

A)A disturbance regime includes defining the predictable frequency and severity of the disturbance.
B)A disturbance regime includes defining the length of the disturbance.
C)A disturbance regime is a more specific type of disturbance.
D)They are essentially the same thing.

Question 39

Figure 53.6
Treehoppers (a type of insect)produce honeydew,which ants use for food.Treehoppers have a major predator,the jumping spider.Researchers hypothesized that the ants would protect the treehoppers from the spiders.In an experiment,researchers followed study plots with ants removed from the system and compared them to a control plot.In the figure above,what can you conclude?

A)Ants do somehow protect the treehoppers from spiders.
B)Ants do not protect the treehoppers from spiders.
C)Ants reduce the numbers of treehoppers.
D)No specific conclusions can be drawn from this figure.