Competition Exam Prep Krohne Ch.11

Chapter 11 Competition

Multiple Choice

1. Which of the following is not characteristic of interspecific competition?
2. One or more resources is limiting.
3. The population size of at least one species decreases.
4. The limiting resource does not change over time.
5. Two or more species interact.
6. none of the above
7. Connell concluded that Semibalanus and Chthamalus compete because
8. Semibalanus cannot survive in the lower intertidal.
9. removal of Semibalanus led to colonization by Chthamalus.
10. Chthamalus is able to live high and low in the intertidal.
11. he found that space is not limiting.
12. none of the above
13. The null hypothesis in a deWitt replacement experiment
14. assumes that interspecific and intraspecific competition are equivalent.
15. determines the outcome of the experiment.
16. assumes that interspecific competition is greater than intraspecific competition.
17. assumes that intraspecific competition is greater than interspecific competition.
18. none of the above
19. Diffuse competition
20. is the result of diffuse resources.
21. occurs when one species preempts space.
22. is the result of many competitors.
23. is the result of a single dominant competitor.
24. none of the above
25. Which of the following does not directly affect the intensity of competition?
26. the presence of similar species
27. niche overlap
28. niche breadth
29. the density of competitors
30. none of the above
31. According to the competitive exclusion principle,
32. resources exclude competitors
33. intraspecific competitors exclude interspecific competitors
34. two species can occupy the same realized niche.
35. two species cannot coexist on the same limiting resource.
36. none of the above
37. Character displacement
38. is the result of selection to decrease niche overlap.
39. is the result of selection to increase niche breadth.
40. is the result of disruptive selection.
41. requires diffuse competition.
42. none of the above
43. Adaptive radiations are likely to occur
44. when species face increased competition.
45. when competition decreased competition.
46. only on islands.
47. after islands are connected to the mainland.
48. none of the above
49. The term α₂₁N₁ measures the
50. degree to which species 1 reduces the resources available to species 2.
51. degree to which species 2 reduces the resources available to species 1.
52. carrying capacity for species 1.
53. carrying capacity for species 2.
54. none of the above
55. The value of niche overlap () increases when the
56. proportional use of the resource by species 1 and 2 are different.
57. proportional use of the resource by species 1 and 2 are similar.
58. squared resource use is 1.0.
59. carrying capacity changes.
60. none of the above
61. In the Lotka-Volterra graphs, an isocline determines
62. where each species is isolated.
63. the rate of change of competition.
64. where population growth is zero.
65. where population growth is maximal.
66. none of the above
67. The Lotka-Volterra models show that coexistence is more likely if niche overlap is
68. small and the carrying capacities are different.
69. large and the carrying capacities are similar.
70. small and the carrying capacities are similar.
71. is similar and the carrying capacities are different.
72. none of the above
73. The realized niche
74. is an adaptive response to competition.
75. is the immediate effect of a competitor on the fundamental niche.
76. is always larger than the fundamental niche.
77. evolves over many generations.
78. none of the above
79. Self-thinning
80. occurs when different tree species compete.
81. is the increase in population size and decrease in individual size.
82. is the decrease in population size and increase in individual size.
83. prevents overpopulation.
84. none of the above
85. In a deWitt replacement series, the most intense interspecific competition occurs when
86. the null hypothesis is rejected.
87. the numbers of individuals of the two species are equal.
88. the numbers of individuals of the two species are most different.
89. if the performance of one species is the same as that of the other.
90. none of the above
91. The songs of black-capped and mountain chickadees
92. both shift by character displacement in sympatry.
93. do no shift by character displacement in sympatry.
94. shift by character displacement only in the subordinate species.
95. shift by character displacement in allopatry.
96. none of the above
97. When the land bridge formed between North and South America,
98. character displacement occurred.
99. marsupials invaded North America.
100. placental mammals invaded North America.
101. placental carnivores drove some marsupials extinct.
102. none of the above

True/False

1. Competition occurs only between related taxa.
2. Semibalanus and Chthamalus compete for light resources.
3. Disturbance can reduce the intensity of competition.
4. Competitive exclusion occurs if niche overlap is too large.
5. The fundamental niche is the role of the organism in the environment.
6. Species that are allopatric cannot compete.
7. Fugitive species are poor competitors
8. Lotka-Volterra isoclines must be straight lines.
9. Character displacement is the result of reduced competition.
10. When disturbance is frequent, competition is often less intense.

Short Answer/Fill in the Blank

1. In __________ competition one species reduces the resource available to the other; in __________ competition one species reduces access to the resource.
2. The functional niche is the __________ whereas the __________ is set of biological and physical resources that determine fitness.
3. What are the conditions that lead to coexistence in the Lotka-Volterra model?
4. To demonstrate that competition is occurring one must show that __________.
5. Directional selection on the niche to reduce overlap leads to __________.
6. When competition occurs, the realized niche is __________ than the fundamental niche.
7. Why is the carrying capacity difficult to measure?