品牌课程 >> 动物世界
标签：动物世界,BBC,中级,英语,蜉蝣,白蚁
蜉蝣（Mayfly）是目前已知的寿命最短的昆虫。蜉蝣栖于水溪和池塘中，雄虫成群飞舞以吸引雌虫。春夏两季，从午后至傍晚，常有成群的雄虫进行“婚飞”，雌虫独自飞入群中与雄虫配对，产卵于水中。
白蚁（Termite）生存在地球已经有二亿五千万年之久，它们不但是历史最悠久的动物，而且还是最伟大的建筑师，这从它们所构筑的蚁冢即可证明。白蚁群居，以木质纤维为食，一旦侵入住房和木制品，难防治，危害极大。
1. add up to 合计达，总括起来、意味着
原句：It adds up to a billion dollars of damage a year.
每年造成的损失高达数十亿美元
例句：I don't think these facts will add up to anything.
这些事实我看不说明任何问题。
2. neither...nor (既)不……也不，(既)非……也非
原句：Brine flies are people friendly, they neither bite nor land on humans.
盐湖蝇不会伤害人类不会叮人，也不会黏着人不放。
例句：The movie is neither attractive nor interesting.
这部电影既不吸引人也不有趣。
3. descend on 袭击(突然降临，突然到达)
原句：They descended on a few particular valleys
他们抵达某几个特别的谷地去。
例句：The robbers descended on us at lunch-time.
午饭时, 抢劫者袭击了我们。
The United States is one of the world's best places
to see manic swarms of insects.
Some have a death wish,
others replicate by the billion.
First the Mississippi River at La Crosse, Wisconsin
On a hot July evening
by the side of this mighty river
millions upon millions of mayflies
take to the air for a single devastating act
to mate and then die.
Reproduction is more important than living.
Mayflies can't even eat.
They don't have mouths,
and they only have enough energy to fly once.
They mate and they crash into the water,
pouring out their eggs as they die.
From this final act comes a stream of new life,
a pattern unbroken for nearly four hundred million years.
But up until now,
there were no cities with bright lights
to lure them away,
so millions of mayflies die without ever laying their eggs,
leaving a scene of insect devastation.
In Florida
humans are under siege from swarms of insects
wood chewing termites.
These tiny white creatures
build their own homes alright,
but they build them inside someone else's.
A swarm of half a million termites
can eat nearly five tons of wood a year.
Multiply that by millions of termite colonies
and it adds up to a billion dollars of damage a year,
more than fire and weather disasters put together.
These swarms have a very personal impact.
In California, east of San Francisco,
Lies Mono Lake.
It's so salty that little lives here
except primitive algae and the insects.
This is the domain of the brine flies,
the main survivors of this barren place.
There are few competitors to keep their numbers down.
At the peak of the season
two thousand tons of flies swarm around the shore.
But brine flies are people friendly,
they neither bite nor land on humans.
A little further north in the Sierra Nevada,
we find another group of insects
swarming to survive.
Lady birds, everywhere.
On winds a mile up,
they've hitched a 50 mile ride from central California
and descended on a few particular valleys
to escape the heat of summer.
Here they sit out
the rest of the summer and winter,
only returning in the spring
when the wind starts to blow the other way.
And these lady birds know exactly
where the wind will carry them.
Which isn't really surprising.
like many of nature swarms
Insects have been traveling the world
in this way for millions of years.
想观赏发狂似的昆虫群体
全球就以美国是最佳景点
有些虫子要完成死前的心愿
其他虫子也大举跟进
首先我们来到威斯康辛州拉克罗斯市的密西西比河岸
时值炎热的七月傍晚
在这条壮丽的河边
数以百万计的蜉蝣
飞向空中，执行一项致命任务
交配后死亡
繁衍后代要比活命更重要
蜉蝣甚至不能进食
因为它们没有嘴巴
它们的体力只够飞行一次
交配完毕，便跌落河面
产卵后就死亡
然而临死前的行动带来新的生命
相同的繁殖模式
四亿年来几乎没有中断
但直到目前为止
城市里没有聚光物引诱它们
上百万的蜉蝣未产卵就死去
徒增昆虫灭亡的一景
在佛罗里达州
人类已经受到虫群的包围
这就是嗫食木头的白蚁
这些微小的白色生物
想要建造自己的家
却偏偏选择盖在别人家里
五十万只的白蚁大军
每年可吃掉近五吨的木材
再乘以百万个白蚁群体
每年造成的损失高达数十亿美元
比火灾和天灾的损失还严重
这些生物群对人类生活带来严重影响
在加州旧金山东部
就是莫诺湖所在地
湖水盐度过高，少有生物可存活
但原始的藻类和昆虫除外
这里是盐湖蝇的地盘
是能在这种荒地存活的主要生物
盐湖蝇少有天敌来抑制数量
在繁殖季节的高峰
重达二千吨的蝇会集结在湖岸边
但盐湖蝇不会伤害人类
不会叮人，也不会黏着人不放
稍往北走，到内华达山脉
又发现另一群昆虫
群聚在一起以求生存
这是瓢虫，到处都是
迎风向前飞一英里
就等于从加州中部搭乘五十英里的顺风车
抵达某几个特别的谷地去
以避开暑热
瓢虫在这里度过余夏和冬天
只有春天才会回去
当风吹相反的方向时
这些瓢虫很清楚
风会把它们带往何处
这没什么值得大惊小怪的
一如自然界中其他的生物群
昆虫也行遍全世界
如此度过了数百万年
【Key Words】
1. replicate v.复制
Some have a death wish, others replicate by the billion.
有些虫子要完成死前的心愿，其他虫子也大举跟进。
2. lure v.吸引，引诱
There were no cities with bright lights to lure them away.
城市里没有聚光物引诱它们。
3. survivor n.幸存者
This is the domain of the brine flies, the main survivors of this barren place.
这里是盐湖蝇的地盘，这是能在这种荒地存活的主要生物。
4. hitch v.免费搭(车旅行)
On winds a mile up, they've hitched a 50 mile ride from central California.
迎风向前飞一英里就等于从加州中部搭乘五十英里的顺风车。
5. devastating adj.毁灭性的
Millions upon millions of mayflies take to the air for a single devastating act to mate and then die.
数以百万计的蜉蝣飞向空中，执行一项致命任务。
【More Words】
Mississippi River 密西西比河
Florida 佛罗里达
California 加利福尼亚
Sierra Nevada 内华达山脉
Wisconsin 威斯康星州
San Francisco 圣弗兰西斯科
mighty adj.强有力的，强大的
reproduction n.繁殖, 生殖
barren adj.贫瘠的
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