extinction rates. (d) water availability and solar radiation levels are highest in the tropics. (e) high temperature causes rapid speciation.

Transcription

1 NOTE: Questions # that follow may have been based in part on material supplied by a textbook publisher. For that reason, the answers to them are provided free (as they were to the students that semester. To get these free answers, go to The major factor responsible for seasons on Earth is (a) global wind patterns. (b) changes in the distance from Earth to sun during the year. (c) Earth s tilt on its axis. (d) vertical air circulation over the oceans. (e) ocean currents. 58. Which of the following investigations is an example of the study of an abiotic factor? (a) Identifying food sources for a bird species. (b) A research project on competition between species. (c) Research on the interaction between two barnacle species on intertidal rocks. (d) A thesis about the relationship between annual precipitation and distribution of a plant species. (e) All of these. 59. Trees most likely to avoid extinction during periods of extensive climate change are those whose seeds (a) have thin seed coats. (b) are easily dispersed by wind or animals. (c) fall close to the parent tree. (d) must be exposed to fire before they will germinate. (e) have a large amount of stored carbohydrate. 60. What are the major factors that determine the climax vegetation in a biome? (a) distance from the equator (b) animal communities the feed on plants (c) temperature and available moisture (d) extent to which the landscape is divided into islands (e) presence of nearby islands. 61. If a certain pine species survives only in scattered areas at elevations above 2,800 m, ecologists seeking an explanation for this distribution should (a) analyze soils looking for unique chemicals. (b) focus on both biotic and abiotic factors unique to high altitudes. (c) study the pine species anatomy. (d) try transplanting the species seeds to lower elevations. 62. Which of the following biomes are at least partly dependent on periodic burning? (a) grassland and tundra (b) chaparral and savanna (c) desert and savanna (d) tropical forest and coniferous forest (e) temperate broadleaf forest and tropical forest. 63. When humans suppress fire in a biome, (a) forest communities remain in healthy condition. (b) species diversity generally increases. (c) threatened and endangered species are protected. (d) species composition within biological communities can change. (e) None of these events occur when fire is suppressed. 64. You would expect two similar plant species that live on different continents and are in different families, but occupy the same biome, to (a) interbreed. (b) also have different temperature and moisture requirements. (c) occupy the same ecological niche. (d) have similar temperature but quite different moisture requirements. (e) exhibit convergent evolution. 1

2 65. The growing season would generally be shortest in which of the following biomes? (a) temperate grasslands (b) coniferous forest (c) temperate broadleaf forest (d) tropical rain forest (e) savanna. 66. Which of the following biomes is correctly paired with the description of its climate? (a) tundra-long summers, mild winters (b) temperate broadleaf forest-short growing season, mild winters (c) tropical forests-nearly constant day length and temperature (d) temperate grasslands-relatively warm winters, most rainfall in summer (e) savanna-low temperature, uniform precipitation. 67. African cattle egrets, Bubulcus ibis, easily spread through parts of the New World, most likely because (a) there were no New World egret species in its ecological nice. (b) no New World parasites could infect B. ibis. (c) temperature and moisture were similar to parts of Africa. (d) B. ibis evolved to compete with local egrets. (e) there were no egret predators in the New World. 68. Which of the following is characteristic of most terrestrial biomes? (a) clear boundaries between adjacent biomes (b) a distribution predicted mainly by rock and soil patterns (c) average annual rainfall in excess of 250 cm (d) vegetation demonstrating vertical layering (e) cold winter months. 69. When climbing a mountain, we can observe transitions in biological communities that are analogous to changes (a) in biomes at different latitudes. (b) in an ecosystem as it changes over time. (c) in a community through different seasons. (d) at different depths in the ocean. (e) across the United States from east to west. 70. According to the competitive exclusion principle, two species cannot continue to occupy the same (a) biome. (b) territory. (c) habitat. (d) ecological niche. (e) range. 71. The sum total of an organism s interaction with the biotic and abiotic resources of its environment is called (a) biotic potential. (b) logistic population growth. (c) an ecological niche. (d) its habitat. (e) its carrying capacity. 72. In Connell s study of barnacles, which of the following best explains the vertical distribution of the different genera? (a) cooperative displacement (b) primary succession (c) predation of one genus by the other genus (d) mutualism (e) competitive exclusion. 73. Which of the following best describes resource partitioning? (a) competitive exclusion and success of a superior species (b) slight variations in niches that allow similar species to coexist (c) a climax community with no new niches available (d) decrease in species diversity due to different resource utilization (e) two species co-evolving to share the same ecological niche. 74. Evidence shows that some grasses benefit from being grazed. Which of the following terms would best describe this plant-herbivore interaction? (a) commensalism (b) predation (c) mutualism (d) parasitism (e) competition. 2

3 75. Which of the following would an ecologist consider most important in understanding the structure of a natural community? (a) which species are present (b) species richness (c) relative abundance of species (d) interactions that occur among the various species (e) All of these. 76. Species richness of a community refers to the (a) complexity of the food web. (b) number of species present. (c) relative number of individuals of each species. (d) total number of all organisms. 77. Which of the following members of a marine food chain occupies a similar trophic level to a grasshopper in a terrestrial food chain? (a) lobster (b) shark (c) sea lion (d) phytoplankton (e) zooplankton. 78. Approximately how many kg of carnivore production can be supported by a field plot containing 2,000 kg of plant material? (a) 20,000 (b) 2,000 (c) 200 (d) 20 (e) In a tide pool, fifteen species of invertebrates were reduced to eight after one species removed. The species removed was most likely a (a) mutualistic organism. (b) keystone species. (c) herbivore. (d) resource partitioner. (e) community facilitator. 80. You are most likely to observe primary succession in a terrestrial community when you visit (a) an abandoned field. (b) a recently plowed field. (c) a recently created volcanic island. (d) a tropical rain forest. (e) a recently burned forest. 81. You are most likely to observe secondary succession in a terrestrial community when you visit (a) an abandoned field. (b) a recently plowed field. (c) a recently created volcanic island. (d) a tropical rain forest. (e) a recently burned forest. 82. In terrestrial communities, species richness of most taxa tends to increase as you (a) travel north from the south pole. (b) climb a mountain near the equator. (c) visit islands of increasing distance from the mainland. (d) visit the same biomes on larger continents. (e) travel north from the tropics. 83. Among islands formed about the same time and at similar distances from a mainland, you would expect the highest species diversity to be on (a) the smallest island. (b) the island formed first. (c) the island formed last. (d) the largest island. (e) You cannot predict species diversity in this case. 84. Among those same islands (question #83) which one would have the most impoverished species diversity? (a) the smallest island. (b) the island formed first. (c) the island formed last. (d) the largest island. (e) You cannot predict species diversity in this case. 85. Among those same islands (question #83), which one would have the lowest extinction rate? (a) the smallest island. (b) the island formed first. (c) the island formed last. (d) the largest island. (e) You cannot predict species diversity in this case. 3

4 86. Among those same islands (question #83), which one would have the highest extinction rate? (a) the smallest island. (b) the island formed first. (c) the island formed last. (d) the largest island. (e) You cannot predict species diversity in this case. 87. Among those same islands (question #83), which one would have the highest immigration rate? (a) the smallest island. (b) the island formed first. (c) the island formed last. (d) the largest island. (e) You cannot predict species diversity in this case. 88. Among those same islands (question #83), which one would have the lowest immigration rate? (a) the smallest island. (b) the island formed first. (c) the island formed last. (d) the largest island. (e) You cannot predict species diversity in this case. 89. Feeding relationships among species on the largest island determine the island community s (a) species richness. (b) species-area curve. (c) secondary succession. (d) trophic structure. (e) immigration rate. 90. The principle of competitive exclusion states that (a) two closely related species cannot coexist on the same island. (b) two species cannot coexist in exactly the same ecological niche. (c) two species will stop reproducing until one species leaves the habitat. (d) two species cannot exist in the same habitat. (e) competition promotes survival of the best adapted species. 91. In a community, keystone predators can maintain diversity if they (a) allow immigration of other predator species. (b) competitively exclude other predator species. (c) prey on the community s dominant species. (d) prey mainly on the least abundant species in a community. (e) reduce disruption in a community. 92. In a community, food chains are sometimes short because (a) only one herbivore species feeds on each plant species. (b) most energy in a trophic level is lost as it passes to the next highest level. (c) most producers are inedible. (d) predator species are less diverse and less abundant than prey species. (e) local extinction of a species causes extinction of other species in a food chain. 93. Based on the intermediate disturbance hypothesis, a community s diversity is (a) increased when humans intervene to stop disturbance. (b) increased by extensive human-caused disturbance. (c) increased by moderate levels of disturbance. (d) increased by stable conditions with no disturbance. (e) increased by frequent massive disturbance. 94. According to the equilibrium model of island biogeography, species richness would be greatest on an island that is (a) environmentally homogeneous. (b) small and close to a mainland. (c) large and remote. (d) small and remote. (e) large and close to a mainland. 95. The best explanation of why species richness is highest in the tropics is that (a) tropical communities are younger than temperate ones. (b) biodiversity increases as evapotranspiration decreases. (c) tropical regions have high immigration rates and low 4

5 extinction rates. (d) water availability and solar radiation levels are highest in the tropics. (e) high temperature causes rapid speciation. 96. A population is considered to (a) inhabit the same area and belong to the same species. (b) inhabit the same area and have a uniform density. (c) belong to the same species and have a uniform density. (d) belong to the same species and have uniform dispersion. (e) inhabit the same area and have uniform density and dispersion. 97. Which of the following processes or properties is considered by ecologists to be a measure of a community s ability to either resist change or recover from disturbance? (a) productivity (b) stability (c) resource partitioning (d) succession (e) competitive exclusion. 98. The most common kind of spatial distribution of a species population in nature is (a) uniform. (b) clumped. (c) dispersive. (d) random. 99. Relatively uniform spacing patterns of certain plants are most often associated with (a) patterns of high humidity. (b) concentration of nutrients within the population s range. (c) competitive interactions among individuals in the population. (d) pure chance. (e) random distribution of seeds Most ecologists believe that the global carrying capacity for the human population is (a) 6 to 8 billion. (b) 10 to 15 billion. (c) 15 to 20 billion. (d) 20 to 25 billion. (e) limitless, provided agricultural technology advances at a certain rate. 5