英语听力：自然百科 野性俄罗斯之西伯利亚 Siberia—11

 Thousands of years of isolation¹ turned them into a separate species. In the middle of the lake are the Ushkanyi islands. Here the seals form their colonies safe from human predation. After a dip in the lake, nothing beats a dry resting place on the lake-side rocks. Getting onto them / is by no means easy using flippers. But underwater, they are hydrodynamic torpedoes², zipping along at up to 25 kilometers per hour. 

 

The oldest and deepest lake in the world, over 1.5 kilometers, originated more than 20 million years ago when two tectonic plates drifted apart. They are still separating at about six millimeters a year. 

 

Down here, the Baikalian sponge colony resembles a coral reef. It can even survive under complete ice cover. Sixty percent of the creatures found here are unique to the lake. While some animals are tiny, the oxygen-rich water enables extreme growth in others. Some amphipods in Baikal can reach 90 millimeters. Deep in the lake, life and death quietly play out. Snails³ clean up a rotting fish. Others are busy mating in the cold waters. 

 

Fifty stories up on the surface, Baikal prepares for an invasion – caddis flies.

1 isolation   

n.隔离，孤立，分解，分离

参考例句：

• The millionaire lived in complete isolation from the outside world.这位富翁过着与世隔绝的生活。
• He retired and lived in relative isolation.他退休后，生活比较孤寂。

2 torpedoes   

鱼雷( torpedo的名词复数 )； 油井爆破筒； 刺客； 掼炮

参考例句：

• We top off, take on provisions and torpedoes, and go. 我们维修完，装上给养和鱼雷就出发。
• The torpedoes hit amidship, and there followed a series of crashing explosions. 鱼雷击中了船腹，引起了一阵隆隆的爆炸声。

3 snails   

n.蜗牛；迟钝的人；蜗牛( snail的名词复数 )

参考例句：

• I think I'll try the snails for lunch—I'm feeling adventurous today. 我想我午餐要尝一下蜗牛——我今天很想冒险。 来自《简明英汉词典》
• Most snails have shells on their backs. 大多数蜗牛背上有壳。 来自《简明英汉词典》