纪录片《我们的地球》 第103期 奇幻沙漠(20)（在线收听）

A single shower can enable seeds that have lain dormant for 30 years or more to burst into life.

一场大雨使得在地下沉睡了30多年的种子迸发出生命的活力

And there hasn't been a bloom like this one for a century.

这里已有一个世纪没有像现在这样开满鲜花

The periods of boom in Death Valley are short

死亡谷中的花期很短

but they're just frequent enough to keep life ticking over.

但它们发生的次数足以保证生命长盛不衰

A sudden flush of vegetation is what every desert dweller waits for

植物的突然兴盛是所有沙漠动物都盼望的事

and when it happens, they must make the most of it.

一旦发生，它们必须尽可能地利用它

There is no other species on the planet that responds as quickly and as dramatically to the good times as the desert locust.

当好日子到来时，地球上再也没有其它物种能像沙漠蝗那样迅速而又戏剧性地作出反应。

Eggs that have remained in the ground for 20 years begin to hatch.

在地下埋藏了20年的虫卵开始孵化

The young locusts are known as hoppers, for at this stage they're flightless.

沙漠蝗的若虫是跳跃能手，在这一阶段，它们还不能飞。

They find new feeding grounds by following the smell of sprouting grass.

它们循着萌发的草香寻找新的用餐场所

Normally it takes four weeks for hoppers to become adults.

一般说来，若虫需要经过4周才能变成成虫

But when the conditions are right, as now, their development switches to the fast track.

但如果条件允许，譬如现在，它们的生长过程就会切换到快车道。

As the vegetation in one place begins to run out,

当一个地方的植物即将吃光时

the winged adults release pheromones, scent messages,

长着翅膀的成虫便释放出信息素，即一些气味信号

which tell others in the group that they must move on.

提醒蝗群中的其它成员它们应该动身了

And when groups merge, they form a swarm.

蝗群合并之后形成了一团蝗虫云。