Deck 14: Exploitative Interactions: Predation, Herbivory, Parasitism, and Disease

Question 1

Which of the following is not an example of altered behavior of the pill bug, Armadillidum vulgare, when infected by the parasite, Plagiorhynchus cylindraceus?

A) Spends less time in sheltered areas
B) Positive phototaxis
C) Spends more time in low humidity environments
D) Seeks out light substrates
E) All are examples of altered behavior of the pill bug when infected by the parasite

Answer 1

B

Question 2

Which of the following factors can stabilize predator-prey relationships by providing a prey refuge?

A) An area of prey habitat where predators cannot enter
B) An area of prey habitat that is isolated and difficult for predators to find
C) The occurrence of prey in numbers too large for predators to attack effectively
D) The ability of prey to grow to a size invulnerable to predation
E) All of the choices are correct.

Answer 2

E

Question 3

Select all of the following that correctly describe graphical representations of the Lotka-Volterra predator-prey model (Select all that apply.)

A) Predator and prey numbers are plotted against time producing reciprocal oscillations in predator-prey populations.
B) Predator numbers are plotted against prey numbers producing reciprocal oscillations in predator-prey populations.
C) Predator and prey numbers are plotted against time producing an elliptical oscillation in predator-prey numbers.
D) Predator numbers are plotted against prey numbers producing an elliptical oscillation in predator-prey numbers.
E) The difference in predator and prey numbers is plotted against population density producing a sigmoid curve that levels off at the carrying capacity.

Answer 3

A, D

Question 4

The defensive tactic in which prey reduce their individual probability of being eaten by occurring at very high densities is called

A) prey satiation.
B) prey dilution.
C) predator dilution.
D) predator satiation.
E) predator masting.

Question 5

Bethel and Holmes demonstrated

A) positive phototaxis in Acanthocephalans infected by amphipods.
B) negative phototaxis in Acanthocephalans infected by amphipods.
C) positive phototaxis in amphipods infected by Acanthocephalans.
D) negative phototaxis in amphipods infected by Acanthocephalans.
E) increased herbivory by amphipods infected by Acanthocephalans.

Question 6

The presence of parasitic protozoa in a culture of competing Tribolium castaneum and T. confusum

A) can reverse the outcome of competition.
B) decreases the likelihood of coexistence.
C) has no effect on the outcome of competition.
D) increases the likelihood of coexistence.
E) has an effect on the outcome of competition only in the presence of predatory birds.

Question 7

Which of the following is a result of infection of Arabis by the plant parasite Puccinia monoica?

A) Formation of an elongated rosette topped by a cluster of bright yellow leaves
B) Formation of a pseudoflower that resembles the flower of a buttercup
C) Insect transfer of spermatia from one fungus to another
D) Elimination of seed formation by the host plant
E) All of the choices are correct.

Question 8

Which statement about snowshoe hare and lynx populations in boreal Canada is false?

A) Lynx are not the only important predator of snowshoe hares.
B) Lynx and hare populations both oscillate repeatedly, with a similar period.
C) Snowshoe hares rarely deplete their food supply enough to affect their population biology.
D) Trapping records kept by non-scientists can provide useful records of hare population sizes.
E) Field experiments imply that hare cycles depend both on the hares' food and their predators.

Question 9

Plagiorhynchus worms and Puccinia rusts are parasites that share the ability to change their host's behavior in way that

A) increase the length of time they can survive in their hosts.
B) decrease their host's mortality rates.
C) increase their hosts reproduction, thereby increasing production of parasite-infected offspring.
D) increase the likelihood of their (the parasites') transmission to a new host.
E) decrease the hosts' vulnerability to other parasites.

Question 10

In the Lotka-Volterra predation model, a prey (host) population in the absence of predators would

A) grow exponentially.
B) grow logistically.
C) grow exponentially, and then crash when it has outstripped its own food supply.
D) decline to extinction.
E) The model makes no assumptions about what happens in the absence of predators.

Question 11

A "negatively phototaxic" amphipod will swim

A) away from parasitic worms.
B) toward parasitic worms.
C) away from competing amphipods.
D) toward light.
E) away from light.

Question 12

Which statement is not true of lynx and coyote predation of the snowshoe hare?

A) Lynx and coyote both show a strong numerical response to increases in the snowshoe hare population.
B) Lynx show higher predation rates when snowshoe hare numbers are declining.
C) Coyotes show higher predation rates when snowshoe hare numbers are increasing.
D) Coyotes show a clear type 2 functional response to increases in the snowshoe hare population.
E) At high hare densities, coyote and lynx predation rates exceed their daily energy needs.

Question 13

A species feeding on the tissue of its host, while not killing it directly, is a

A) predator.
B) parasite.
C) parasitoid.
D) cannibal.
E) debilitator.

Question 14

Gause's experiments with Paramecium and Didinium showed

A) extinction of the predator, followed by extinction of the prey, in all habitats.
B) coexistence of predator and prey at fairly constant population sizes, in all habitats.
C) coexistence of predator and prey, but with oscillating population sizes, in all habitats.
D) coexistence of predator and prey at fairly constant population sizes, but only in the presence of refuges and predator reservoirs.
E) coexistence of predator and prey with oscillating population sizes, but only in the presence of refuges and predator reservoirs.

Question 15

In the Lotka-Volterra model, the rate of predation is represented by

A) c.
B) p.
C) cp.
D) d_pN_p
E) d_p

Question 16

In the Lotka-Volterra predation model, the predator death rate is represented by

A) c.
B) p.
C) cp.
D) d_pN_p.
E) d_p.

Question 17

The Lotka-Volterra predation model predicts that predators and prey, living together, will show

A) oscillations in population size that increase in amplitude through time.
B) oscillations in population size that remain of constant amplitude through time.
C) oscillations in population size that decrease in amplitude through time.
D) oscillations, but only when outside forces such as climatic variation are also present.
E) steady equilibria in population sizes.

Question 18

________ consume live plant material but do not usually kill plants.

A) Predators
B) Pathogens
C) Herbivores
D) Parasites
E) Parasitoids

Question 19

Periodical cicadas spend 13 or 17 years

A) feeding in tree twigs before emerging as adults.
B) feeding on tree roots before emerging as adults.
C) as adults before laying eggs.
D) in a resistant, resting egg before hatching as larvae.
E) None of the choices are correct.

Question 20

In the Lotka-Volterra predation model, a predator population in the absence of prey (hosts) would

A) grow exponentially.
B) grow logistically.
C) decline as predators die.
D) decline at first, but then increase as predators switch to other modes of feeding.
E) decline at first, but then reach a small equilibrium population size.

Question 21

Match each element from a functional response model to its correct meaning.

A) handling time
B) rate of prey availability
C) per capita availability of prey
D) prey abundance
E) searching time
α

Question 22

Birds are more effective predators than bats on foliage-living arthropods in tropical lowland forests.

Question 23

Which of the following is not a hypothesis that was proposed to explain population dynamics of lynx and snowshoe hares?

A) Overpopulation of hares leads to reduced food quantity and quality.
B) Lynx populations grow in response to increasing hare availability, and then eventually reduce hare populations.
C) Variation in intensity of solar radiation affects hares and their food supply, and lynx populations respond to changes in hare abundance.
D) Variation in the severity of winters drives changes in hare populations, which in turn influences lynx abundance.
E) Overpopulation of hares leads to high levels of stress, causing the population to decline.

Question 24

An organism inducing disease in its host is called a ________.

Question 25

Match each element from a functional response model to its correct meaning.

A) handling time
B) rate of prey availability
C) per capita availability of prey
D) prey abundance
E) searching time
a

Question 26

Research by Erik Lindström and his colleagues clearly showed that red foxes have significant influence on the abundance of mountain hares

Question 27

Match each element from a functional response model to its correct meaning.

A) handling time
B) rate of prey availability
C) per capita availability of prey
D) prey abundance
E) searching time
N/P

Question 28

Bats affect the cost of agriculture because

A) they consume crops and must be controlled.
B) they eat crop pests and reduce the amount of pesticides used.
C) they eat crop pests and reduce the amount of crop loss.
D) they eat crop pests and reduce both the amount of crop loss and the amount of pesticides used.
E) their flight patterns interfere with agricultural machinery.

Question 29

Neither the prey-dependent model nor the ratio-dependent model of functional response incorporates the number of predators in the environment.

Question 30

You are designing an experiment to test whether the emergence of large numbers of moths over a short time period provides an effective refuge. You hypothesize that the moths are employing predator satiation. If you are correct, what response do you expect to see in your experiment?

A) The percentage of prey consumed increases sharply as the prey density increases from low to medium, but levels off at high prey densities.
B) The percentage of prey consumed increases gradually as the prey density increases from low to medium to high.
C) The percentage of prey consumed remains stable as the prey density increases from low to medium, then decreases at very high prey densities.
D) The percentage of prey consumed increases sharply as the prey density increases from low to medium, but decreases at high prey densities.

Question 31

________ is the idea that predators can have non-lethal effects on prey's behavior in which they avoid high-risk locations.

Question 32

In Lamberti and Resh's experiment, what was the purpose of having a second grid of tiles raised 15cm above the stream bottom?

A) To prevent algae and bacteria from colonizing the tiles
B) To encourage algae and bacteria to colonize the tiles
C) To prevent Helicopsyche from colonizing the tiles
D) To encourage Helicopsyche to colonize the tiles

Question 33

You are studying the response of microscopic predatory nematodes to various prey densities. The nematodes live in soil and have a short life cycle. What model is likely to be the most appropriate?

A) A prey-dependent functional response model
B) A numerical response model
C) A ratio-dependent functional response model

Question 34

Match each element from a functional response model to its correct meaning.

A) handling time
B) rate of prey availability
C) per capita availability of prey
D) prey abundance
E) searching time
h

Question 35

In most laboratory experiments, predators and prey held together in simple habitats exhibit repeated cycles in population sizes.

Question 36

Match the organism with the correct type of exploitation.

A) predator
B) pathogen
C) parasite
A dragonfly larva lives in a pond where it hunts and kills tadpoles and other insects.

Question 37

Match the organism with the correct type of exploitation.

A) predator
B) pathogen
C) parasite
A tapeworm lives in the intestines of a dog, where it absorbs nutrients.

Question 38

Match the organism with the correct type of exploitation.

A) predator
B) pathogen
C) parasite
Plasmodium spp. enter the liver and red blood cells of humans and other vertebrates, sometimes causing malaria.

Question 39

Match each element from a functional response model to its correct meaning.

A) handling time
B) rate of prey availability
C) per capita availability of prey
D) prey abundance
E) searching time
N

Question 40

Why was the field experiment by Krebs and colleagues so important to our understanding of predator and prey dynamics?

A) Because the researchers were able to manipulate three trophic levels simultaneously in the field and on a large scale
B) Because the researchers were able to manipulate three trophic levels simultaneously without the influence of complicating factors such as weather cycles
C) Because the researchers were able to test for the effects of the three trophic levels one at a time, in three separate experiments
D) Because the researchers were able to manipulate three trophic levels as well as normally complicating factors such as weather and genetics

Question 41

What methods and/or tools did Cleveland et al. use in their study of Brazilian free-tailed bats? (Select all that apply.)

A) NEXRAD Doppler radar
B) Ground-based observation
C) Cotton bollworm survival rates
D) Radio tagging of bats
E) Avoided-cost analysis

Question 42

The value of pest control by Brazilian free-tailed bats varies across years because cotton bollworm ________ varies from year to year.