Effects of Plate Tectonics on Species
Effects of Plate Tectonics on Species
Plate tectonics is the theory that attempts to explain the large-scale motions of great plates of Earth’s crust as they move about over geologic time. These motions have had a great effect on the biology of all the continents. Although the relationship between the plate tectonic processes and the evolution of life is complex, data from fossil remains provide convincing evidence of the influence of plate movement on the distribution of organisms.
The present distribution of plants and animals is not random but is controlled largely by climate and geographic barriers. The world’s biota-its collection of plant and animal life-occupy biotic provinces, regions characterized by distinctive assemblages of plants and animals. Organisms within a province have similar ecological requirements, and the boundaries that separate provinces are therefore natural ecological breaks. Climatic or geographic barriers are the most common province boundaries, and these are largely controlled by plate movements.
Because adjacent provinces usually have less than 20 percent of their species in common, global diversity is a direct reflection of the number of provinces; the more provinces there are, the greater the global diversity. When continents break up, for example, the opportunity to form new provinces increases, with a resultant increase in diversity. Just the opposite occurs when continents come together. Plate tectonics thus plays an important role in the distribution of organisms and their evolutionary history.
Complex interactions of wind and ocean currents have a strong influence on the world’s climates. These currents are influenced by the number, distribution, topography, and orientation of the continents. For example, the southern Andes Mountains of South America act as an effective barrier to moist, easterly blowing Pacific winds, resulting in a desert east of the southern Andes that is virtually uninhabitable. Temperature is one of the major limiting factors for organisms, and province boundaries often reflect temperature barriers. Because atmospheric and oceanic temperatures decrease from the equator to the poles, most species exhibit a strong distribution into climatic zones. This biotic zonation parallels the world’s latitudinal atmospheric and oceanic circulation patterns. Changes in climate thus have a profound effect on the distribution and evolution of organisms.
The distribution of continents and ocean basins not only influences wind and ocean currents, but also affects provinciality by creating physical barriers to, or pathways for, the migration of organisms. Intraplate volcanoes (those in the middle of tectonic plates), subduction zones (places where one tectonic plate dives under another), island arcs (series of islands created from the volcanic activity triggered by plate movement in a subduction zone), mid-oceanic ridges, and mountain ranges all result from the interaction of plates, and their orientation and distribution strongly influence the number of provinces and hence total global diversity. Thus, provinciality and diversity will be highest when there are numerous small continents spread across many zones of latitude.
When a geographic barrier separates a fauna(collection of animal life) that was previously uniform, species may undergo divergence. If conditions on opposite sides of the barrier are sufficiently different, then species must adapt to the new conditions, migrate, or become extinct. Adaptation to the new environment by various species may involve enough change that new species eventually evolve. The marine invertebrates found on opposite sides of the Isthmus of Panama provide an excellent example of divergence caused by the formation of a geographic barrier. Prior to the rise of this land connection between North and South America, a homogenous population of bottom- dwelling invertebrates inhabited the shallow seas of the area. After the rise of the Isthmus of Panama about 5 million years ago, the original population was divided. In response to the changing environment, new species evolved on opposite sides of the isthmus.
The formation of the Isthmus of Panama also influenced the evolution of the North and South American mammalian faunas. During most of the Cenozoic Era (starting roughly 65 million years ago), South America was an island continent, and its mammalian fauna evolved in isolation from the rest of the world’s faunas. When North and South America were connected by the Isthmus of Panama, most of the indigenous South American mammals were replaced by migrants from North America. Surprisingly, only a few South American mammal groups migrated northward.
1
Plate tectonics is the theory that attempts to explain the large-scale motions of great plates of Earth’s crust as they move about over geologic time. These motions have had a great effect on the biology of all the continents. Although the relationship between the plate tectonic processes and the evolution of life is complex, data from fossil remains provide convincing evidence of the influence of plate movement on the distribution of organisms.
According to paragraph 1, in what way are fossil remains useful for studying the biology of the continents?
Factual Information Questions事实信息题
AThey show that the continents originally had similar patterns of organism distribution.
BThey show that the evolution of life is affected by many complex influences.
CThey show that organism distribution is affected by tectonic plate movement.
DThey help explain the distribution of Earth’s geologic plates.
2
The present distribution of plants and animals is not random but is controlled largely by climate and geographic barriers. The world’s biota-its collection of plant and animal life-occupy biotic provinces, regions characterized by distinctive assemblages of plants and animals. Organisms within a province have similar ecological requirements, and the boundaries that separate provinces are therefore natural ecological breaks. Climatic or geographic barriers are the most common province boundaries, and these are largely controlled by plate movements.
According to paragraph 2, all of the following are true of biotic provinces EXCEPT:
Negative Factual Information Questions否定事实信息题
AEach contains plants and animals with similar ecological needs.
BThey are often separated by climatic or geographic barriers.
CTheir boundaries are natural ecological breaks.
DOrganisms in nearby biotic provinces have similar ecological requirements.
3
Because adjacent provinces usually have less than 20 percent of their species in common, global diversity is a direct reflection of the number of provinces; the more provinces there are, the greater the global diversity. When continents break up, for example, the opportunity to form new provinces increases, with a resultant increase in diversity. Just the opposite occurs when continents come together. Plate tectonics thus plays an important role in the distribution of organisms and their evolutionary history.
According to paragraph 3, which of the following explains one way in which plate tectonics affects species diversity?
Factual Information Questions事实信息题
AWhen continents come together, the opportunity for species diversity increases.
BWhen continents pull apart, the locations available for species diversification increase.
CWhen continents move into new climate zones, the existing species of the continent are replaced with new species.
DWhen continents come together, the new provinces that are created usually contain more species than the old provinces did.
4
Complex interactions of wind and ocean currents have a strong influence on the world’s climates. These currents are influenced by the number, distribution, topography, and orientation of the continents. For example, the southern Andes Mountains of South America act as an effective barrier to moist, easterly blowing Pacific winds, resulting in a desert east of the southern Andes that is virtually uninhabitable. Temperature is one of the major limiting factors for organisms, and province boundaries often reflect temperature barriers. Because atmospheric and oceanic temperatures decrease from the equator to the poles, most species exhibit a strong distribution into climatic zones. This biotic zonation parallels the world’s latitudinal atmospheric and oceanic circulation patterns. Changes in climate thus have a profound effect on the distribution and evolution of organisms.
In paragraph 4, why does the author mention “ the southern Andes Mountains of South America”?
Rhetorical Purpose Questions修辞目的题
ATo give an example of a continental feature that interacts with wind or ocean currents to affect climate
BTo give an example of a desert caused by the position of a mountain.
CTo give an example of the kind of climate caused by ocean winds.
DTo give an example of how climate patterns are affected by the presence or absence of moisture from winds.
5
Complex interactions of wind and ocean currents have a strong influence on the world’s climates. These currents are influenced by the number, distribution, topography, and orientation of the continents. For example, the southern Andes Mountains of South America act as an effective barrier to moist, easterly blowing Pacific winds, resulting in a desert east of the southern Andes that is virtually uninhabitable. Temperature is one of the major limiting factors for organisms, and province boundaries often reflect temperature barriers. Because atmospheric and oceanic temperatures decrease from the equator to the poles, most species exhibit a strong distribution into climatic zones. This biotic zonation parallels the world’s latitudinal atmospheric and oceanic circulation patterns. Changes in climate thus have a profound effect on the distribution and evolution of organisms.
The word “ parallels” in the passage is closest in meaning to
Vocabulary Questions词汇题
Amatches
Bdetermines
Ccontains
Dalters
6
The distribution of continents and ocean basins not only influences wind and ocean currents, but also affects provinciality by creating physical barriers to, or pathways for, the migration of organisms. Intraplate volcanoes (those in the middle of tectonic plates), subduction zones (places where one tectonic plate dives under another), island arcs (series of islands created from the volcanic activity triggered by plate movement in a subduction zone), mid-oceanic ridges, and mountain ranges all result from the interaction of plates, and their orientation and distribution strongly influence the number of provinces and hence total global diversity. Thus, provinciality and diversity will be highest when there are numerous small continents spread across many zones of latitude.
According to paragraph 5, each of the following is a factor affecting the overall number of biotic provinces in the world EXCEPT
Negative Factual Information Questions否定事实信息题
ATotal global species diversity
BThe number of continents
CThe interactions of tectonic plates
DThe distribution of ocean basins
7
When a geographic barrier separates a fauna(collection of animal life) that was previously uniform, species may undergo divergence. If conditions on opposite sides of the barrier are sufficiently different, then species must adapt to the new conditions, migrate, or become extinct. Adaptation to the new environment by various species may involve enough change that new species eventually evolve. The marine invertebrates found on opposite sides of the Isthmus of Panama provide an excellent example of divergence caused by the formation of a geographic barrier. Prior to the rise of this land connection between North and South America, a homogenous population of bottom- dwelling invertebrates inhabited the shallow seas of the area. After the rise of the Isthmus of Panama about 5 million years ago, the original population was divided. In response to the changing environment, new species evolved on opposite sides of the isthmus.
The word “ shallow” in the passage is closest in meaning to
Vocabulary Questions词汇题
Anearby
Bcalm
Chaving a moderate temperature
Dhaving little depth
8
The formation of the Isthmus of Panama also influenced the evolution of the North and South American mammalian faunas. During most of the Cenozoic Era (starting roughly 65 million years ago), South America was an island continent, and its mammalian fauna evolved in isolation from the rest of the world’s faunas. When North and South America were connected by the Isthmus of Panama, most of the indigenous South American mammals were replaced by migrants from North America. Surprisingly, only a few South American mammal groups migrated northward.
In paragraph 7, the discussion of the effect of the rise of the Isthmus of Panama on mammal populations of North and South America suggests which of the following?
Factual Information Questions事实信息题
AMost South American mammals that migrated to North America were successful there.
BBefore the formation of the Isthmus of Panama, there were fewer mammal species in North America than in South America.
CMigrating species are better adapted to the areas they migrate to than they are to the areas they migrate from.
DEvolving in isolating may not prepare species to successfully compete with invading species.
9
Because adjacent provinces usually have less than 20 percent of their species in common, global diversity is a direct reflection of the number of provinces; the more provinces there are, the greater the global diversity. [■] When continents break up, for example, the opportunity to form new provinces increases, with a resultant increase in diversity.[■] Just the opposite occurs when continents come together. [■] Plate tectonics thus plays an important role in the distribution of organisms and their evolutionary history. [■]
Complex interactions of wind and ocean currents have a strong influence on the world’s climates. These currents are influenced by the number, distribution, topography, and orientation of the continents. For example, the southern Andes Mountains of South America act as an effective barrier to moist, easterly blowing Pacific winds, resulting in a desert east of the southern Andes that is virtually uninhabitable. Temperature is one of the major limiting factors for organisms, and province boundaries often reflect temperature barriers. Because atmospheric and oceanic temperatures decrease from the equator to the poles, most species exhibit a strong distribution into climatic zones. This biotic zonation parallels the world’s latitudinal atmospheric and oceanic circulation patterns. Changes in climate thus have a profound effect on the distribution and evolution of organisms.
Look at the four squares [■] that indicate where the following sentence could be added to the passage
Certain kinds of plate interactions tend to increase the number of provinces.Insert Text Questions句子插入题
Where would the sentence best fit？Click on a square sentence to the passage.
10
Life is spread among the world’s biotic provinces, each of which supports a particular combination of organisms.
Prose Summary Questions概要小结题
Select 3 answers
AAs a result of tectonic plate movements, organisms in a province become so dependent on other organisms in the same province that very few of them can survive in a different biotic province.
BSpecies distribution and diversity may be affected by plate-created geographic features that either allow organisms to travel to other biotic provinces or prevent them from doing so.
CTectonic plate movements affect diversity mainly by changing the characteristics of the surrounding environment rather than by dividing uniform populations into separate groups.
DTectonic plate movements and climate can affect species distribution partly because they can affect temperature, which is a strong factor in determining where a given organism can live.
EGlobal species diversity is related to the overall number of biotic provinces, and both of these are highest when many small continents exist and are spread out across a wide range of latitudes.
FTectonic plates tend to move fastest in areas where the ocean currents are the strongest, resulting in a faster rate of extinction of species living on nearby land areas.
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