PLANET EARTH Great Plains

Vast open plains. Immense spaces. Eerie（可怕的） silence but any feeling of emptiness is an illusion. The plains of our planet support the greatest gatherings of wildlife on Earth. At the heart of all that happens here is a single living thing. Grass. This miraculous（不可思議的） plant covers a quarter of all the lands of the Earth. Grasslands exist where ever there is a little rain, but not enough to sustain the forests. Some are huge.



The Central Asian Steppe（中亞大草原） alone extends one third of the way around our planet. It's summer and eagles effortlessly cruise the thermals scanning the ground beneath for signs of prey. In the distant reaches of Outer Mongolia（外蒙古，原為中國領(lǐng)土的一部分，后獨(dú)立成立蒙古人民共和國） one of the planet's great migrations is underway. Few people ever see this extraordinary annual event. Mongolian gazelle. Two million are thought to live here but no one really knows.



For much of the time they're scattered through this vast landscape but once a year they come together to have their young. Nearly all will give birth within the next ten days. Out in the open, communal calving（聚眾產(chǎn)仔，communal表示公共的，calve表示產(chǎn)犢） is the safest way to have young. With so many pairs of eyes keeping watching it's almost impossible for predators to sneak up（悄悄接近）. There are no bushes, no trees, there's only one thing to hide behind, grass, and it's not very effective. Vast open plains. Immense spaces. Eerie（可怕的） silence but any feeling of emptiness is an illusion. The plains of our planet support the greatest gatherings of wildlife on Earth. At the heart of all that happens here is a single living thing. Grass. This miraculous（不可思議的） plant covers a quarter of all the lands of the Earth. Grasslands exist where ever there is a little rain, but not enough to sustain the forests. Some are huge.



The Central Asian Steppe（中亞大草原） alone extends one third of the way around our planet. It's summer and eagles effortlessly cruise the thermals scanning the ground beneath for signs of prey. In the distant reaches of Outer Mongolia（外蒙古，原為中國領(lǐng)土的一部分，后獨(dú)立成立蒙古人民共和國） one of the planet's great migrations is underway. Few people ever see this extraordinary annual event. Mongolian gazelle. Two million are thought to live here but no one really knows.



For much of the time they're scattered through this vast landscape but once a year they come together to have their young. Nearly all will give birth within the next ten days. Out in the open, communal calving（聚眾產(chǎn)仔，communal表示公共的，calve表示產(chǎn)犢） is the safest way to have young. With so many pairs of eyes keeping watching it's almost impossible for predators to sneak up（悄悄接近）. There are no bushes, no trees, there's only one thing to hide behind, grass, and it's not very effective.