英语听力：探索发现 2012-10-03 长毛象王国 Mammoth—11

 At its maximum, the ice covered nearly six million square miles. And in places, it was up to two miles thick. The ice blanket was punctuated¹ only by occasional islands of rock, the peaks of the very highest mountains.

 

Though Beringia itself remained largely ice-free, it still felt the effects of the ice sheets. Cold, dry air flow down the glaciers² and out across surrounding lands. The freezing dry winds blasting off the ice created conditions in which only grasses and other small plants would flourish. There were advantages: the wind also prevented snow from building up so grass remained accessible throughout the year. In such cold temperatures, this was a lifeline for the mammoths, bison and other grazers, which, in turn, sustained other beasts of Beringia.

 

Another widespread Beringian animal that depended on the ice age wind was the dull sheep. Dull sheep needed the snow to be blown clear from their winter grazing. And today they have the same priority. They are found only on the most exposed and wind-swept mountain slopes. In the autumn, dull rams³, like the mammoths and the mask oxen, become focused on the urge to mate.

1 punctuated   

v.（在文字中）加标点符号，加标点( punctuate的过去式和过去分词 )；不时打断某事物

参考例句：

• Her speech was punctuated by bursts of applause. 她的讲演不时被阵阵掌声打断。
• The audience punctuated his speech by outbursts of applause. 听众不时以阵阵掌声打断他的讲话。 来自《简明英汉词典》

2 glaciers   

冰河，冰川( glacier的名词复数 )

参考例句：

• Glaciers gouged out valleys from the hills. 冰川把丘陵地带冲出一条条山谷。
• It has ice and snow glaciers, rainforests and beautiful mountains. 既有冰川，又有雨林和秀丽的山峰。 来自英语晨读30分（高一）

3 rams   

n.公羊( ram的名词复数 )；(R-)白羊（星）座；夯；攻城槌v.夯实（土等）( ram的第三人称单数 )；猛撞；猛压；反复灌输

参考例句：

• A couple of rams are butting at each other. 两只羊正在用角互相抵触。 来自辞典例句
• More than anything the rams helped to break what should have been on interminable marriage. 那些牡羊比任何东西都更严重地加速了他们那本该天长地久的婚姻的破裂。 来自辞典例句