英语听力：2013-04-05 恐龙之战之极限生存 Extreme Survivors—8

T-Rex is impressive and it's powerful, but compare to Ankylosaurus, it is relatively lightly built. Protective plates made of bone and cartilage covered this lumbering creature from head to tail. Light, but extremely strong, the hide of Ankylosaurus

英语听力：2013-04-03 恐龙之战之极限生存 Extreme Survivors—7

Male lions defend their cubs against rivals who see their offspring as future competition for food and mates. So its likely that an intelligent predator like T-Rex would do the same. Compared to prehistoric plant eaters, its cerebrum, the part of the

英语听力：2013-03-31 恐龙之战之极限生存 Extreme Survivors—6

When you start off coming out of the egg and youre less than, say, 2 feet long and you are in a world full of predators that are loving to crunch on you, then you need to get big fairly quickly. The future seems bleak for this dinosaur. With its life

英语听力：2013-03-29 恐龙之战之极限生存 Extreme Survivors—5

There probably werent many animals of Cretaceous that would dare to try to grab a baby Tyrannosaurus Rex. Quetzalcoatlus could probably manage it. If you see a stork on the Nile today eating a baby crocodile, you can imagine in your mind Quetzalcoatl

英语听力：2013-03-27 恐龙之战之极限生存 Extreme Survivors—4

Tyrannosaurus Rex when we think about it, we tend to think of the big adult because thats the skeletons that we see, but we know that they didnt hatch that way. Once those eggs hatched, weve got an animal thats maybe, you know, three feet long, maybe

英语听力：探索发现 2013-03-10 猛玛象进城记 Mammoths to Manhattan—18

This mass roosting takes place soon after the summer nesting season. Its a chance for the birds to molt before they fly south for the winter. As Vauxs swift numbers reach a peak in mid September, they attract attention from the locals. Coopers hawks

英语听力：探索发现 2013-03-08 猛玛象进城记 Mammoths to Manhattan—17

But there is at least one place in Florida where the manatees benefit from humans being around. Clean, hot water released from this power plant turns a man-made inlet into a hot tub. And during winter months when sea temperatures drop below 20 degree

英语听力：探索发现 2013-03-06 猛玛象进城记 Mammoths to Manhattan—16

This disused car park is a near-perfect location for raising chicks, and only a short flight from a plentiful supply of food. Skimmers get their name from their unusual feeding technique--their extended lower bill detects fish just below the water su

英语听力：探索发现 2013-03-03 猛玛象进城记 Mammoths to Manhattan—15

Moose mainly browse on trees and shrubs, but they will also sample something new. They have a soft spot for pumpkins left out after Halloween. As many as 1,000 moose may enter Anchorage in winter, snowfall here is lower than its surrounding hills and

英语听力：探索发现 2013-03-01 猛玛象进城记 Mammoths to Manhattan—14

Although many of these city foxes do get killed by cars, the population as a whole is thriving. Thats because a regular supply of water means a regular supply of prey, including voles and ground squirrels. Playing on the streets at night is dangerous

英语听力：探索发现 2013-02-27 猛玛象进城记 Mammoths to Manhattan—13

The owls can raise anything from 1 to 12 chicks in a summer season. To survive, their young will have to quickly learn to negotiate the dangers of city life. Longer hunting trips are sometimes necessary as open land disappears. But so long as the cit

英语听力：探索发现 2013-02-24 猛玛象进城记 Mammoths to Manhattan—12

And farming fuelled the growth of another habitat, one that would become an even bigger challenge to North America's wildlife. The modern city was born. The city is an artificial environment, built around the needs of millions of people, and yet it a

英语听力：探索发现 2013-02-22 猛玛象进城记 Mammoths to Manhattan—11

At first, the Europeans relied heavily on local food supply by native people. But as they settled in, their farming practices began to shape the landscape of North America. The plow allowed them to farm larger areas of land, helping to feed the expan

英语听力：探索发现 2013-02-20 猛玛象进城记 Mammoths to Manhattan—10

Where purple martins had once laid their eggs in hollow threes, in time, they came to rely almost totally on people to provide nests for them. These artificial nests were made from dried out squashes known as gourds. The shape made them perfect nesti

英语听力：2013-03-15 猛玛象进城记 Mammoths to Manhattan—20

Its also a prime hunting ground for red-tailed hawks. And they have the perfect nesting site right next to it. Theyd moved in on the top floor of this expensive Manhattan apartment block. It acts like a surrogate tree, supporting their large nest. Th

英语听力：2013-03-13 猛玛象进城记 Mammoths to Manhattan—19

Its incredible that so many birds cram into the tiny spaces underneath the bridge. But the battle for living spaces is now an everyday fact of city life. The most populated North American city is New York. Here space is a precious commodity with more

英语听力：2013-03-17 猛玛象进城记 Mammoths to Manhattan—21

This may look like a safari through the African savanna. In fact it's a theme park in Florida. And it allows people to experience a world outside their own. In some ways, they are visiting a land from another time. 14 thousand years ago, large parts

英语听力：2013-03-20 恐龙之战之极限生存 Extreme Survivors—1

In a world of terrifying creatures, being small means facing danger at every turn. If you were a small animal, the late cretaceous would have been an awful time to be around. For a youngster, every day is a struggle to stay alive. Their only chance i

英语听力：2013-03-22 恐龙之战之极限生存 Extreme Survivors—2

I think its a very beautiful idea that you have this little egg thats surprisingly small and out of it comes a baby sauroposeidon thats about the size of a rabbit and in two or three decades, its gonna be a 50-ton adult. But why does this huge animal

英语听力：2013-03-24 恐龙之战之极限生存 Extreme Survivors—3

Its reputation for violence and terror is unmatched, but an infant T-Rex comes into the world better protected than most. If you say Tyrannosaurus Rex, I think of gentleness. I think of superb motherhood and a struggle to raise ones chicks. The dread