纪录片《我们的地球》 第90期 奇幻沙漠(07)

Any kangaroo out in the open is in serious danger of overheating.

任何一只呆在外面的袋鼠都将面临中暑的威胁

In the full sun, the temperature on the ground soars to 70 degrees.

待到阳光最毒辣之时，地面温度已升高至70℃

By midday, the radiation is so intense they must take shelter.

到了正午，太阳的炙焰迫使它们不得不寻找庇荫处

In the shade, they are shielded from much of the sun's energy

在树荫下，它们虽然避开了太阳的能量

but their body temperature can still rise.

但它们的体温仍在升高

So they lick saliva¹ onto their forearms

所以它们将唾液抹在前臂上

where there is a network of blood vessels² close to the surface of the skin,

那里的血管网比较贴近皮肤表层

and as the saliva evaporates, their blood is cooled.

因此，当唾液蒸发时，血液也能得到冷却

This thermal³ image shows just how effective the process is.

这幅热影像能证明这种方法非常有效

The blue areas on the body are the cooler parts.

身上蓝色的部分是较冷的部位

As the saliva dries, it has to be replaced.

唾液干了之后还得重新抹上

And this is a real drain on the kangaroo's body fluids.

袋鼠真正排放出去的体液也就是这些

Even in the shade, the earth is baking hot.

即使是在树荫下，土地照样被烤得火热

So the kangaroos dig away the warmed topsoil to get at the cooler ground beneath.

于是袋鼠刨去灼烫的表层沙土，贴近下面较冷的地面。

1 saliva   

n.唾液，口水

参考例句：

• He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
• Saliva dribbled from the baby's mouth.唾液从婴儿的嘴里流了出来。

2 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

3 thermal   

adj.热的，由热造成的；保暖的

参考例句：

• They will build another thermal power station.他们要另外建一座热能发电站。
• Volcanic activity has created thermal springs and boiling mud pools.火山活动产生了温泉和沸腾的泥浆池。