Ecology 203, Exam III. April 19, 2000 Name ______________________________
Rules: Read carefully, work accurately and efficiently. Answer questions to the best of your ability. You usually have a choice. [SS] = student submitted question. Good luck!
Multiple Choice. Then circle the number of the question you want evaluated (2 pts each; 40 pts total). I WILL OMIT YOUR FIRST WRONG ANSWER
1. In the movie the Connell-Janson Hypothesis stated that diversity was maintained because [SS]
a. seed dispersal and sapling growth is favored in gaps of light
b. dispersal is favored near the parent
c. dispersal is favored away from the parent
d. all of the above
e. none of the above
2. The new theory that explains the mechanism of maintaining diversity is [SS]
a. seed dispersal is favored away from the parent
b. gaps of light are colonized randomly (lottery like) so that a more
competitive species cannot take over an area
c. seed dispersal is favored near the parent
d. a and b
e. no theory currently explains the maintenance of diversity.
3. Diversity increases with
a. increasing altitude
b. increasing latitude
c. decreasing productivity
d. decreasing precipitation
e. none of the above.
4. "Response to competition" is
a. measured in units area
b. the reduction in a population due to competition
c. the reduction in size of an individual due to the presence of neighbors
d. the reduction in size due to predation.
e. all of the above are aspects of this concept.
5. Thomas Park’s work on Tribolium revealed
a. the effect of predators on herbivores
b. the effect of herbivores on plants
c. the effect of disease dynamics on insects
d. the effect of temperature and moisture on competitive interactions
e. all of the above
6. From what you have learned in Ecology about how science works it would be fair to say that scientists generally look for
a. confirmation of their hypotheses
b. data to disprove their hypotheses
c. data to prove their hypotheses
d. surprises in results
e. ways to make themselves famous, almost at all costs
7. To determine that competition occurs in a two-species system we should
a. remove one species and see how the other responds.
b. place organisms together and see if there is an effect.
c. see if organisms that grow together in one place seem to
do worse than those that occur elsewhere in isolation.
d. these are all ways to test for competition
e. one can’t really test for competition.
8. Character displacement is evidence
a. that a species has mutated.
b. that two species have mutated
c. that two species experienced competition in the past
d. that species with intermediate traits are now extinct
e. none of the above.
9. In the above graph H = herbivores present, P = predators present, and C = controls. The graph suggests that
a. plants are more numerous when fertilized.
b. plants grow most when fertilized
c. plants without fertilizer have the most leaf area with herbivores and predators present.
d. plants with fertilizer have the most leaf area.
e. plants are unaffected by herbivores.
10. In the experiment from the previous question fertilizer did the following when herbivores and
predators were present:
a. reduced the herbivore population but increased the predator population.
b. increased the herbivore population but decreased the predator population.
c. increased both herbivore and predator populations.
d. reduced both herbivore and predator populations.
e. none of the above.
11. Reserves designed to maximize the persistence of species should
a. minimize perimeter and maximize area.
b. minimize area but maximize the number of patches.
c. maximize perimeter and area.
d. maximize the number of patches but only if they are connected by corridors.
e. be set up like zoos with a minimum amount of disturbance allowed.
12. Plants often have to protect themselves from herbivores. The types of defense they use are [SS]
a) constituent
b) exaptation
c) induced
d) a and c
e) none of the above
13. Dr. Hartvigsen suggested that, for assessing the shape of things, Euclidean (or standard) geometry is
a. wrong
b. surprisingly useful
c. relatively useless
d. incomplete
e. probably OK since we did not discuss this.
14. Plants
a. can localize induced defenses down to the individual
b. can localize induced defenses down to the branch
c. can localize induced defenses down to the leaf
d. can localize induced defenses down to within individual leaves.
e. can induced constituent defenses at any scale within the plant.
15. The relative shape of beaks of Darwin’s finches in the Galapagos is similar to the relative size of rodents in deserts of the southwest in that they are
a. all relatively evenly distributed among possible sizes.
b. all randomly distributed among possible sizes.
c. all relatively clumped, having similar sizes.
d. all of the above are actually true.
e. none of the above is true.
16. Hairston, Smith, and Slobodkin (1960) suggested that
a. herbivores are regulated by diseases
b. predators are regulated by their predators
c. herbivores are regulated by food supply
d. herbivores are regulated by predators
e. predators are ultimately regulated by plant abundance.
17. The following pair of techniques can be used to determine food web structure:
a. observe what organisms eat and what eats them.
b. observe who eats who and trace isotopes through organisms
c. conduct competition and predation experiments
d. all of these
e. it is not possible to determine food web structure.
18. A "hot spot" is, technically, an area of
a. high species diversity
b. low species diversity
c. high temperatures, usually at very low elevations
d. all of the above
e. none of the above.
19. The Theory of Island Biogeography is generally
a. supported by data
b. refuted by data
c. interesting but has been replaced by metapopulation biology
d. dull, uninteresting, and basically useless to science
e. none of the above.
20. Secondary succession
a. is of secondary importance and occurs in places like new volcanoes.
b. occurs in terrestrial systems, not aquatic systems.
c. is more common than primary succession
d. is an orderly process of community development over time
e. is all of the above.
21. The above graph is most consistent with which theory of community development?
a. Clement’s idea of "relay floristics."
b. Gleason’s idea of the "individualistic concept."
c. Egler’s "initial floristic composition" model.
d. It is consistent with all of them.
e. It is consistent with none of them.
Extremely short answers (5 pts each)
1. Fill in "+" for positive effects, "-" for negative effects, and "0" for no effect. (feel free to explain)
Interaction type Species A Species B
Competition
Predation
Herbivory
Mutualism
2. Alter the following equation to include a competitor: dN1/dt = r1N1((K1 – N1)/K1) below.
Provide brief, accurate definitions in the space provided (5 pts each)
Interspecific Competition
Induced vs. constituative defenses [SS]
ANALYZE THE GRAPHS You should know what to do. Discussions are unnecessary. (5 pts each).
1.
2.
Graph the following relationships. Your graphs should be complete with well-labeled axes so that they need no discussion. Use only the space provided.
1. The herbivore optimization hypothesis
2. The intermediate disturbance hypothesis
3. The Theory of Island Biogeography. Include lines for the different combinations of factors discussed. ANALYZE THE GRAPH.
Longer answer but just answer this sufficiently – do not conduct a brain dump. Graphs ALWAYS help explain answers to questions! (CHOOSE ONLY ONE; USE JUST THIS SIDE OF THE PAPER) (10 pts)
1. Design a competition experiment for two plant species. Discuss the two types of measures of competition you should use. Provide a graph of expected results and report the type of competition "observed."
2. Discuss the following statement: "disease agents should evolve toward the state of benign coexistence."