英语听力：2013-07-24 《恐龙的战争》3 顽强防御—17

 Individually, their huge size is a powerful defense¹, but sticking together makes these Leviathans almost indestructible. Keeping a herd² of 50-ton animals filled up, however, means traveling vast distances, grazing territory covering thousands of square kilometers. And moving a mountain of flesh requires sophisticated coordination³. 

 

One of the curious things about sauropods is that they did have a swelling⁴ in the spinal⁵ cord in the neighborhood of their pelvis. It is sort of like a second brain to help control the back half of the body.

 

It’s called the sacro-lumbar expansion, a bundle of nerves which acts like a primitive⁶ brain controlling the movements of the legs and tail. The brain in a Sauroposeidon’s head is simply too small and far away to coordinate⁷ its front and back legs. So a second brain operates the back end of the animal. 

 

The reason why animals like Sauroposeidon have an enlargement in their hip⁸ is because there’s actually a lot going on back there. There are lots of muscles that are in the legs, and also muscles that are going through the tail. 

 

The primitive brain in its pelvis keeps Sauroposeidon’s legs and tail in sync with its body. Without it, they could never have grazed over such large territories or possibly, they wouldn’t have even been able to walk at all. This tiny bundle of nerves weighing just a few grams allows herds⁹ of Sauroposeidon to rule the great plains of the southern Midwest of America for almost 15 million years. 

 

Another plant eater couldn’t appear more different. It’s small, weak, and highly intelligent. But like Sauroposeidon, Parasaurolophus live in herds. They stick together and are constantly on the lookout¹⁰ for threats. But for Parasaurolophus, there’s a problem. Their eyes …

1 defense   

n.防御，保卫；[pl.]防务工事；辩护，答辩

参考例句：

• The accused has the right to defense.被告人有权获得辩护。
• The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。

2 herd   

n.兽群，牧群；vt.使集中，把…赶在一起

参考例句：

• She drove the herd of cattle through the wilderness.她赶着牛群穿过荒野。
• He had no opinions of his own but simply follow the herd.他从无主见，只是人云亦云。

3 coordination   

n.协调，协作

参考例句：

• Gymnastics is a sport that requires a considerable level of coordination.体操是一项需要高协调性的运动。
• The perfect coordination of the dancers and singers added a rhythmic charm to the performance.舞蹈演员和歌手们配合得很好，使演出更具魅力。

4 swelling   

n.肿胀

参考例句：

• Use ice to reduce the swelling. 用冰敷消肿。
• There is a marked swelling of the lymph nodes. 淋巴结处有明显的肿块。

5 spinal   

adj.针的，尖刺的，尖刺状突起的；adj.脊骨的，脊髓的

参考例句：

• After three days in Japan,the spinal column becomes extraordinarily flexible.在日本三天，就已经使脊椎骨变得富有弹性了。
• Your spinal column is made up of 24 movable vertebrae.你的脊柱由24个活动的脊椎骨构成。

6 primitive   

adj.原始的；简单的；n.原(始)人，原始事物

参考例句：

• It is a primitive instinct to flee a place of danger.逃离危险的地方是一种原始本能。
• His book describes the march of the civilization of a primitive society.他的著作描述了一个原始社会的开化过程。

7 coordinate   

adj.同等的，协调的；n.同等者；vt.协作，协调

参考例句：

• You must coordinate what you said with what you did.你必须使你的言行一致。
• Maybe we can coordinate the relation of them.或许我们可以调和他们之间的关系。

8 hip   

n.臀部，髋；屋脊

参考例句：

• The thigh bone is connected to the hip bone.股骨连着髋骨。
• The new coats blouse gracefully above the hip line.新外套在臀围线上优美地打着褶皱。

9 herds   

兽群( herd的名词复数 )； 牧群； 人群； 群众

参考例句：

• Regularly at daybreak they drive their herds to the pasture. 每天天一亮他们就把牲畜赶到草场上去。
• There we saw herds of cows grazing on the pasture. 我们在那里看到一群群的牛在草地上吃草。

10 lookout   

n.注意，前途，瞭望台

参考例句：

• You can see everything around from the lookout.从了望台上你可以看清周围的一切。
• It's a bad lookout for the company if interest rates don't come down.如果利率降不下来，公司的前景可就不妙了。