英语听力：自然百科 澳大利亚大堡礁 Great Barrier Reef—6

 Like these sea fans, the last frontier of life on the reef. The divers¹ reach their target-- a massive ridge², 190 feet down.

 

Here, the air they are breathing is under pressure, squeezed down so that there's more gas in every lungful. They have to hope that the rock gives up before they do. With just minutes left, they must take the rock to the surface. “Let's have a look. What have we got?”

 

For Jody, this is the moment of truth.

 

“Hey, there we go. Yep, yep, yep.”

 

He's the first person to see what's hidden deep below the reef.

 

“Yeah, it's definitely coral in there. You can see skeletal structure in here. Yeah, well, this is definitely coral.”

 

And not just any coral, what they've brought back from the depths seems to defy nature. It's a species of coral that can only grow in shallow water. What could possibly explain this?

 

The Earth's orbit is not stable. Over hundreds of thousands of years, tiny eccentricities³ in its path caused the planet to wobble on its axis⁴. 18, 000 years ago, it was tilted--just one degree, but enough to tip the planet into cold clutches of chaos--an Ice Age.

 

The polar ice caps started expanding aggressively, sucking up water into massive sheets of ice. Oceans dropped in every corner of the world, and the whole shallow sea on Australia's east coast disappeared.

1 divers   

adj.不同的；种种的

参考例句：

• He chose divers of them,who were asked to accompany him.他选择他们当中的几个人，要他们和他作伴。
• Two divers work together while a standby diver remains on the surface.两名潜水员协同工作，同时有一名候补潜水员留在水面上。

2 ridge   

n.山脊；鼻梁；分水岭

参考例句：

• We clambered up the hillside to the ridge above.我们沿着山坡费力地爬上了山脊。
• The infantry were advancing to attack the ridge.步兵部队正在向前挺进攻打山脊。

3 eccentricities   

n.古怪行为( eccentricity的名词复数 )；反常；怪癖

参考例句：

• My wife has many eccentricities. 我妻子有很多怪癖。 来自《简明英汉词典》
• His eccentricities had earned for him the nickname"The Madman". 他的怪癖已使他得到'疯子'的绰号。 来自辞典例句

4 axis   

n.轴，轴线，中心线；坐标轴，基准线

参考例句：

• The earth's axis is the line between the North and South Poles.地轴是南北极之间的线。
• The axis of a circle is its diameter.圆的轴线是其直径。