英语听力：自然百科 神奇水世界 Water-2

The center of the Sahara Desert in North Africa, one of the driest places on earth. I'm over six hours drive from civilization. Temperatures here regularly reach 100 degrees Fahrenheit, but there's less than half an inch of rainfall each year. Ah,the

英语听力：自然百科 神奇水世界 Water-3

Out there is a river valley that's been carved into the rock. It's been carved by running water, just flew down here smoothly off this rock bed and then cascaded down to the valley north there. Six thousand years ago, that was a big river. Satellite

英语听力：自然百科 神奇水世界 Water-4

Let's look first. The fresh water that we depend on begins its life in the oceans. As the sun's rays beat down on the surface of the sea, they heat the water molecules until some evaporate. It's the start of an extraordinary journey. Here with water

英语听力：自然百科 神奇水世界 Water-5

What that circulation means to us human is that water is a moving target. We constantly have to seek it out in this endless cycle and intercept it wherever and whenever we can. This quest depend on water has played a defining role in human history. T

英语听力：自然百科 神奇水世界 Water-6

It worked because the water of the river carried something special within it, an almost invisible treasure that was the secret of Egypts economic might. What made Egypt great is this stuff - silt. It's a rich supermineral silt, it's like an expresso,

英语听力：自然百科 神奇水世界 Water-7

So the rigid hierarchical structure of Egyptian society wasn't just dictated by the Pharaohs. It also emerged because the Egyptians had only one water source - the Nile. 5,000 years ago, it wasn't just the ancient Egyptians who noticed the value of r

英语听力：自然百科 神奇水世界 Water-8

society, that first brought civilization to the desert. Far from just scraping by in this harsh landscape, the Garamantes were flourishing. They grew crops, such as cereals and grapes. They kept horses and pigs. Clearly, they needed large amounts of

英语听力：自然百科 罕见的全黑帝企鹅

This all black feathered king penguin could be one in a zillion. The video was recorded on a sub-Antarctic island of South Georgia by National Geographic Traveler magazine contributing editor Andrew Evans on his bus to Antarctic expedition. While man

英语听力：自然百科 智利大地震

Little Emilia may not know it, but she played a role in the fateful circumstances that saved her family and relatives from serious injury and possibly much worse. It was her baptism that brought the family together in this picturesque region of Chile

英语听力：自然百科 博茨瓦纳

Botswana lies in the arid（不毛的，贫瘠的） basins of southern Africa, much of it within the Kalahari（喀拉哈里沙漠） Desert. But in the north, there is an immense oasis（绿洲） called the Okavango Delta. Created by the floodwate

英语听力：自然百科 马里：独特的成人礼

In the Dogon village of Komokan in Mali, preparations are underway for a rare event, the Village Dama. Damas can be held only after a good harvest, and in this environment, that doesnt happen very often. The Dama is a mask festival that honors deceas

英语听力：自然百科 埃及文物归还原主

A stolen ancient Egyptian sarcophagus is returning home. The sarcophagus nearly three thousand years old was seized by U.S. Immigration and Customs Enforcement or ICE during the routine shipment inspection at the Miami international airport in 2008.

英语听力：自然百科 Indian Hot Spot

Nature reports results from GRACE, a satellite machine designed to use gravity measurement to monitor the world's water resources. GRACE is the Gravity Recovery and Climate Experiment and it's a two-satellite machine. These two satellites are followi

英语听力：自然百科 来自远古宇宙的光

When massive stars explode, they can produce gamma-ray bursts. The burst, reported in two papers in Nature, is the earliest descriptive event seen so far in our universe. When I received the text message about the gamma-ray burst, it came ultimately

英语听力：自然百科 美国大陆最南端：西屿

Althoughit has become a tourist town, the islands in a place where things are donejust a little differently. Itsknown for its literature from Ernest Hemmingway to Tom Corporate Key West hasalways been a favorite siting for authors. Thestory of the Ke

英语听力：自然百科 仙人掌 peyote

Outsiders call it peyote. The Huichol, an indigenous tribe in western Mexico, call it hikuri, and they teach their children to use it. While most societies outlaw this consciousness-altering drug, Mexico permits the tribe to use it as the central exp

英语听力：自然百科 印度的繁华旧梦：Goa

In 1498, the Portuguese became the first Europeans to reach India by sea. They came in search of spices and Christian souls, spices they found in abundance, but the Christians they would have to generate for themselves. The capital city of old Goa qu

英语听力：自然百科 世上最早的四足动物

Nature's latest report from the world of paleontology challenges the assumptions made by everyone until now about when animals first walked the earth. This is footprint of early tetrapods. We have here, for example, digits, impressions, and something

英语听力：自然百科 论自然与科学

Sir David Attenborough has been making natural history films for the BBC for over 50 years. In this time, he, perhaps more than anyone alive, has seen evidence for evolution in the stunning diversity of nature. To find and film animals. This is the b

英语听力：自然百科 时空探秘

Every year on the beautiful Lindau island of Lake Constance, some of the best of the worlds young scientists meet Nobel Prize winners. As it turned out, this meeting of physicists was a true meeting of minds. And so native created five new films expl