英语听力：自然百科 冰冻星球 前往地球尽头—15（在线收听） |
The randoms of the sea ice are occupied by sun- bathing seals that have been here all winter. But the new arrivals're following the retreating ice edge and they have come here to hunt. Killer whales, the oceans' top predator. Killers are like wolves, for they will hunt animals far larger than themselves. But even smaller prey are a problem, if you can't reach them. The solution is teamwork. Swimming in perfect formation, they flick their tail in unison and create a wave that cracks the ice. They regroup and access the damage. A more powerful wave is needed. The ice float is breaking up. Now they are close enough to get a good look at their target. The seal is a crabeater , sharp to stand feisty, not their favorite. The wolves of the sea move on in search of easier quarry. A weddell seal. That is better. These are more docile and easier to tackle. The pardon stay is close together and travels silently. This time they initiate far more powerful wave and with astonishing accuracy. These big whales are not intended to break the ice, but to knock the prey into the water and they rarely fail. |
| 原文地址：http://www.tingroom.com/lesson/zrbaike/2012/260370.html |