2020职称英语考试理工B级完形填空真题答案
Warmer Climate Will Bake Tropical Bugs
Global warming could cook tropical insects, with
unpredictable knock-on effects, say researchers who warn that rising temperatures also
(51) tropical frogs, lizards (蜥蜴).
Temperatures are (52) to increase much faster in
temperate and polar regions than in the tropics. But no-one had looked at how warming would affect insects and other cold-blooded animals (53) had evolved in tropical regions with little temperature variation.
Curtis Deutsch at the University of California at Los Angeles and colleagues analysed data (54)insect survival and reproduction for 38 species in different ecosystems, and then estimated how these values would (55) with predictions of climate change for the 21st century.
The team found that the reproductive (56) of tropical insects tends to peak very close to the temperatures where they normally live, but (57) sharply at higher temperatures. This means that cranking up the heat only a small amount can
exert a heavy toll, leaving insects unable to reproduce (58) enough to keep up their numbers.
Temperature tolerance
Temperate insects reproduce well over a broader range, and do not live as (59) to their thermal limit, so they can reproduce successfully when their climate warms more than in the tropics.
“Tropical insects do very well in a narrow band of temperatures, but move them above that (60) and they die,” says team member Josh Tewksbury of the University of Washington in Seattle.
The heart of the (61) is temperature tolerance. emperate-zone insects have evolved to survive the much broader temperature swings of seasonal climates, than have their tropical relatives.
The (62) appears worse for animals that live in hot stable climate of the lower levels of tropical forests.
Lizards in clear areas can find shade to cool down, but those living in the forest are already in the (63), and there's not much they can do to get cooler, Deutsch says.
Too few tropical insects have been studied so far to (64) if any particular group will be particularly hard-hit, says Tewksbury. Insects play important (65) in forest ecology, including pollination, and eating detritus to recycle carbon.
The team are now starting to evaluate how temperature
affects ecological interactions of insects with other species, including crops such as African corn.
Journal reference： Proceedings of the National Academy of Sciences (DOI： 10.1073/pnas.0709472105)
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参考答案：
51. threaten 52. expected 53. that 54. On 55. change
56. rate 57 drops 58 fast 59 close 60. range
2020职称英语考试理工B级完形填空真题答案
