Where Have All the Frogs Gone?
In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians are declining or have become extinct. They have been around for a long time - over 350 million years. Why are they dying out now?
The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the earth is becoming unlivable for amphibians, is it also becoming unlivable for other kinds of animals and human beings as well?
There are a number of other factors in amphibian decline. Pollution is one of them. In many industrial areas, air pollution has poisoned the rain, which then falls on ponds and kills the frogs and toads that live there. In farming areas, the heavy use of chemicals on crops has also killed off amphibians. Another factor is that air pollution has led to increased levels of ultraviolet light. This endangers amphibians, which seem to be especially sensitive to UV light. And finally, scientists have discovered a new disease that seems to be killing many species of amphibians in different parts of the world.
36 Losing amphibians means losing
B knowledge about air and water pollution.
D an opportunity to detect poisonous gases.
A in any stream they can find,
C only on sand.
38 The arroyo toad is disappearing because
B it is losing its habitat.
D it cant bear the cold of winter.
A poisonous gases.
C water leakage.
40 Scientists think that the decline of amphibians could
B cause a decline in other kinds of animals.
D be a good sign for human beings.
国内英语资讯:Wang Yang meets Taiwan delegation headed by Kao Chin Su-mei
国际英语资讯:Pakistans finance minister stresses to enhance trade ties with regional countries
国内英语资讯:China, India contribute most to global greenery expansion: NASA data
体坛英语资讯:Olympiacos Piraeus beat Khimki BC 71-57 in Euroleague
国际英语资讯:Japan demands remarks about emperor made by S. Korean assembly speaker be retracted
国内英语资讯:Bill Gates says China a major contributor to global progress
体坛英语资讯:AFC Asian Cup: Hosts UAE, Thailand, Bahrain survive Group A
国内英语资讯:Spring Festival travel brings 513.9 bln yuan to Chinas tourism revenue
国内英语资讯:China to lift another ten million people out of poverty in 2019
国际英语资讯:Hungarian PM announces bold seven-point action plan to fight population decline
娱乐英语资讯:Bands Boney M., Joy to perform in Vietnam
老外亲述:为啥中国人这么喜欢用数字?
国内英语资讯:Chinas EU mission denies groundless reports about Chinese espionage in Brussels
国内英语资讯:Holiday sales of Chinese retail, catering firms up 8.5 pct
国内英语资讯:Chinas largest air carrier serves 2.1 mln passengers in Spring Festival holiday
国际英语资讯:Iraqs PM says solving water pollution prioritized for Iraq
国内英语资讯:Chinese, Japanese officials, scholars call for joint efforts to promote healthy development
国内英语资讯:Chinas top legislature wraps up bimonthly session
最令人难以接受的事实有哪些?
国内英语资讯:China, UK should handle differences properly, enhance strategic mutual trust: Ambassador
国内英语资讯:Senior CPC official stresses improving publicity, ideological workers quality
国际英语资讯:Spotlight: Yemen still in quagmire of conflict 8 years after revolution
国内英语资讯:AU Commission chief extolls AU-China partnership at AU summit
北极熊大举入侵俄罗斯群岛 吓得当地居民不敢出门
国内英语资讯:Chinese envoy calls for improvements on peacekeeping operations
国际英语资讯:U.S. school closures ordered for Monday due to heavy snowstorm
体坛英语资讯:Liga President confirms March 2 as date for next Real Madrid-Barca Clasico
国内英语资讯:Xi signs order to release regulation on military training supervision
国内英语资讯:Chinas top political advisor meets DPRK guest
多年后,我终于变成了最好的自己
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |