Warmer climate will bake tropical bugs 2016年职称英语理工类B级完形填空 （大家先借助谷歌或者百度，有道词典进行翻译哦）
Global warming could cook tropical insects, with unpredictable knock-on effects, say researchers who warn that rising temperatures also threaten tropical frogs, lizards and turtles.
Temperatures are expected 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 that had evolved in tropical regions with little temperature variation.
Curtis Deutsch at the University of California at Los Angeles and colleagues analysed data on insect survival and reproduction for 38 species in different ecosystems, and then estimated how these values would change with predictions of climate change for the 21st century.
The team found that the reproductive rate of tropical insects tends to peak very close to the temperatures where they normally live, but drops 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 fast enough to keep up their numbers.
Temperature tolerance
Temperate insects reproduce well over a broader range, and do not live as close 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 range and they die,” says team member Josh Tewksbury of the University of Washington in Seattle.
Frogs, lizards and turtles face similar problems, although not as much data is available on their temperature tolerance, says Deutsch.
The heart of the problem is temperature tolerance. Temperate-zone insects have evolved to survive the much broader temperature swings of seasonal climates, than have their tropical relatives.
Important role
The effect 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 shade, and there’s not much they can do to get cooler, Deutsch says.
Too few tropical insects have been studied so far to tell if any particular group will be particularly hard-hit, says Tewksbury. Insects play important roles 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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答案：
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52 expected
53 that
54 on
55：change
56;rate
57;drops
58:sucessfully
59;close
60：range
61: problem
62: effect
63: shade
64: tell
65:roles
发表于 2025-5-15 15:45:25
